Flarm in the US [Archive] - AviationBanter

brianDG303[_2_]

August 9th 10, 05:23 PM

On Aug 9, 7:12*am, Renny > wrote:
> On Aug 9, 7:56*am, Mike Schumann >
> wrote:
>
>
>
> > On 8/9/2010 8:43 AM, Steve Freeman wrote:
>
> > > Curious about the use of Flarm in the US. Was told by another pilot
> > > that the frequency used by Flarm is not approved for that category of
> > > use in the US. Is that true? If it is, do they make units that use a
> > > US approved frequency?
>
> > There is virtually no FLARM in the US. *It is unlikely to take off here,
> > as the biggest threats for mid-airs in the US are between powered
> > aircraft and gliders or other aircraft.
>
> > It's a chicken and egg situation. *FLARM is only interesting if everyone
> > equips. *No one is going to equip if they don't think that everyone else
> > will.
>
> > With ADS-B coming out, that is the way to go in the US. *If you buy an
> > ADS-B transceiver, not only will you see other ADS-B equipped aircraft,
> > but, if you are within range of an ADS-B ground station, you will also
> > see all Mode C/S transponder equipped aircraft that are visible to ATC.
> > * With 80-90% of GA aircraft in the US transponder equipped, this gives
> > an immediate benefit to anyone investing in ADS-B (assuming that they
> > have a ground station deployed in their area).
>
> > --
> > Mike Schumann
>
> Mike,
> Your points are all well taken. I realize that FLARM has never been
> accepted in the US up to now, and we all know that ADS-B is coming in
> 2020 (although I thought there was a "glider" exemption), but with
> that being said, would it make any sense for FLARM units to be
> required for gliders competing in any of our nationals (or maybe even
> in regionals)?
>
> As you are aware, we've had several mid-airs between gliders in recent
> years and perhaps if gliders had been equipped with FLARM units in a
> nationals or in a regionals, some of these mid-airs might have been
> prevented.....Just a thought!
>
> Thanks - Renny

Mike and Renny,
a good discussion of the macro view of FLARM and ADS-B. Another view
is more personal, for example in my situation- I fly a lot of ridge
and mountain in a very narrow altitude band and a lot of clouds. There
is not a lot of power traffic in those conditions. I have a
transponder but I don't see the Transmit light going off very often
and I suspect I am not getting very many radar paints down in the
rocks and trees where I like to fly. My greatest risk is from the six
other gliders I share the area with, which do not have transponders
and will never get them at the current costs; in fairness my threat to
them is even higher as I am a low hour pilot. FLARM would go a long
way to reducing the risks and at a reasonable cost; PowerFlarm would
be my choice as it would also provide protection from ADS-B and
transponder equipped threats, but at twice the cost the installed base
in my situation would be very much reduced and I stand a better chance
of talking my potentially deadly friends into investing in FLARM. 2020
is not soon enough. It is not soon enough for the pilots killed on a
regular basis at contests, which we seem to simply accept as an
unavoidable risk.

With that in mind Mike's statement that FLARM isn't of use (for me)
would not be correct. In 2004 my club lost two gliders and a pilot in
a collision that would not have happens if they had had FLARM. How do
you calculate that cost?

Brian

Mike Schumann

August 9th 10, 05:45 PM

On 8/9/2010 9:12 AM, Renny wrote:
> On Aug 9, 7:56 am, Mike >
> wrote:
>> On 8/9/2010 8:43 AM, Steve Freeman wrote:
>>
>>> Curious about the use of Flarm in the US. Was told by another pilot
>>> that the frequency used by Flarm is not approved for that category of
>>> use in the US. Is that true? If it is, do they make units that use a
>>> US approved frequency?
>>
>> There is virtually no FLARM in the US. It is unlikely to take off here,
>> as the biggest threats for mid-airs in the US are between powered
>> aircraft and gliders or other aircraft.
>>
>> It's a chicken and egg situation. FLARM is only interesting if everyone
>> equips. No one is going to equip if they don't think that everyone else
>> will.
>>
>> With ADS-B coming out, that is the way to go in the US. If you buy an
>> ADS-B transceiver, not only will you see other ADS-B equipped aircraft,
>> but, if you are within range of an ADS-B ground station, you will also
>> see all Mode C/S transponder equipped aircraft that are visible to ATC.
>> With 80-90% of GA aircraft in the US transponder equipped, this gives
>> an immediate benefit to anyone investing in ADS-B (assuming that they
>> have a ground station deployed in their area).
>>
>> --
>> Mike Schumann
>
> Mike,
> Your points are all well taken. I realize that FLARM has never been
> accepted in the US up to now, and we all know that ADS-B is coming in
> 2020 (although I thought there was a "glider" exemption), but with
> that being said, would it make any sense for FLARM units to be
> required for gliders competing in any of our nationals (or maybe even
> in regionals)?
>
> As you are aware, we've had several mid-airs between gliders in recent
> years and perhaps if gliders had been equipped with FLARM units in a
> nationals or in a regionals, some of these mid-airs might have been
> prevented.....Just a thought!
>
> Thanks - Renny
>
Why not require ADS-B units instead. Then you'd get the advantages of
FLARM, but you'd also see all of the transponder equipped GA aircraft
(assuming that there was a ground station in the area).

Now that Navworx is shipping their unit, this could happen tomorrow.
I'm sure that someone could talk Navworx into working with the major
glide computer manufacturers to provide the necessary interfaces if they
knew that this would be worth their while.

--
Mike Schumann

Mike Schumann

August 9th 10, 05:48 PM

On 8/9/2010 11:23 AM, brianDG303 wrote:
> On Aug 9, 7:12 am, > wrote:
>> On Aug 9, 7:56 am, Mike >
>> wrote:
>>
>>
>>
>>> On 8/9/2010 8:43 AM, Steve Freeman wrote:
>>
>>>> Curious about the use of Flarm in the US. Was told by another pilot
>>>> that the frequency used by Flarm is not approved for that category of
>>>> use in the US. Is that true? If it is, do they make units that use a
>>>> US approved frequency?
>>
>>> There is virtually no FLARM in the US. It is unlikely to take off here,
>>> as the biggest threats for mid-airs in the US are between powered
>>> aircraft and gliders or other aircraft.
>>
>>> It's a chicken and egg situation. FLARM is only interesting if everyone
>>> equips. No one is going to equip if they don't think that everyone else
>>> will.
>>
>>> With ADS-B coming out, that is the way to go in the US. If you buy an
>>> ADS-B transceiver, not only will you see other ADS-B equipped aircraft,
>>> but, if you are within range of an ADS-B ground station, you will also
>>> see all Mode C/S transponder equipped aircraft that are visible to ATC.
>>> With 80-90% of GA aircraft in the US transponder equipped, this gives
>>> an immediate benefit to anyone investing in ADS-B (assuming that they
>>> have a ground station deployed in their area).
>>
>>> --
>>> Mike Schumann
>>
>> Mike,
>> Your points are all well taken. I realize that FLARM has never been
>> accepted in the US up to now, and we all know that ADS-B is coming in
>> 2020 (although I thought there was a "glider" exemption), but with
>> that being said, would it make any sense for FLARM units to be
>> required for gliders competing in any of our nationals (or maybe even
>> in regionals)?
>>
>> As you are aware, we've had several mid-airs between gliders in recent
>> years and perhaps if gliders had been equipped with FLARM units in a
>> nationals or in a regionals, some of these mid-airs might have been
>> prevented.....Just a thought!
>>
>> Thanks - Renny
>
> Mike and Renny,
> a good discussion of the macro view of FLARM and ADS-B. Another view
> is more personal, for example in my situation- I fly a lot of ridge
> and mountain in a very narrow altitude band and a lot of clouds. There
> is not a lot of power traffic in those conditions. I have a
> transponder but I don't see the Transmit light going off very often
> and I suspect I am not getting very many radar paints down in the
> rocks and trees where I like to fly. My greatest risk is from the six
> other gliders I share the area with, which do not have transponders
> and will never get them at the current costs; in fairness my threat to
> them is even higher as I am a low hour pilot. FLARM would go a long
> way to reducing the risks and at a reasonable cost; PowerFlarm would
> be my choice as it would also provide protection from ADS-B and
> transponder equipped threats, but at twice the cost the installed base
> in my situation would be very much reduced and I stand a better chance
> of talking my potentially deadly friends into investing in FLARM. 2020
> is not soon enough. It is not soon enough for the pilots killed on a
> regular basis at contests, which we seem to simply accept as an
> unavoidable risk.
>
> With that in mind Mike's statement that FLARM isn't of use (for me)
> would not be correct. In 2004 my club lost two gliders and a pilot in
> a collision that would not have happens if they had had FLARM. How do
> you calculate that cost?
>
> Brian

Why not convince your fellow pilots to invest in the Navworx ADS-B
transceiver that is now shipping? FLARM in the US is a dead end. ADS-B
is the future. If you invest in a Navworx type of device, not only
would you see each other, but you will also see other ADS-B equipped GA
aircraft, and if you are flying within range of a ground station, ALL
transponder equipped aircraft.

--
Mike Schumann

Andy[_1_]

August 9th 10, 05:57 PM

On Aug 9, 9:45*am, Mike Schumann >
wrote:

> Why not require ADS-B units instead. *Then you'd get the advantages of
> FLARM, but you'd also see all of the transponder equipped GA aircraft
> (assuming that there was a ground station in the area).

Perhaps because glider pilots would be overwhelmed by nuissance alerts
when contest flying? I have already experienced my PCAS becoming
close to useless as more gliders are fitted with transponders. I
don't need another system crying wolf all the time.

FLARM uses intelligent alerting based on glider flight
characteristics. It has been reported that the nuissance alerting
frequency low enough that it is still useful in high glider traffic
densities.

Andy

Mike Schumann

August 9th 10, 06:29 PM

On 8/9/2010 11:57 AM, Andy wrote:
> On Aug 9, 9:45 am, Mike >
> wrote:
>
>> Why not require ADS-B units instead. Then you'd get the advantages of
>> FLARM, but you'd also see all of the transponder equipped GA aircraft
>> (assuming that there was a ground station in the area).
>
> Perhaps because glider pilots would be overwhelmed by nuissance alerts
> when contest flying? I have already experienced my PCAS becoming
> close to useless as more gliders are fitted with transponders. I
> don't need another system crying wolf all the time.
>
> FLARM uses intelligent alerting based on glider flight
> characteristics. It has been reported that the nuissance alerting
> frequency low enough that it is still useful in high glider traffic
> densities.
>
>
> Andy
>
>
There are two parts to FLARM; an ADS-B type position reporting
broadcast function, and a built in collision warning system.

ADS-B transceivers typically do not include any collision warning logic.
Instead they are more like modems. They transmit and receive position
data in addition to receiving weather info, etc. This information is
passed on to some form of graphics display device so that the locations
of other aircraft can be shown on a moving map display relative to your
own aircraft.

The display device, in addition to showing the location of other
aircraft, can also be programmed to provide collision warnings.
Obviously, the typical flight trajectories of gliders are different than
most power aircraft. I suspect that most glider specific moving map
vendors will try to match FLARM's logic to minimize false alarms if they
elect to provide a collision warning function in addition to just
displaying the relative locations of other aircraft.

ADS-B is obviously just in its infancy in the US vs FLARM's development
in Europe. The encouraging news is that the potential size of the US
ADS-B market is much larger than the potential FLARM market in Europe
(when you include the GA power market), so there will undoubtedly be
lots of innovation in the display devices that will provide the
collision warning function. In VFR environments, these devices will not
require FAA approvals, so I expect that technical advancements will be
very rapid, once low cost ADS-B transceivers become widely available.

--
Mike Schumann

Darryl Ramm

August 9th 10, 06:55 PM

On Aug 9, 9:45*am, Mike Schumann >
wrote:
> On 8/9/2010 9:12 AM, Renny wrote:
>
> > On Aug 9, 7:56 am, Mike >
> > wrote:
> >> On 8/9/2010 8:43 AM, Steve Freeman wrote:
>
> >>> Curious about the use of Flarm in the US. Was told by another pilot
> >>> that the frequency used by Flarm is not approved for that category of
> >>> use in the US. Is that true? If it is, do they make units that use a
> >>> US approved frequency?
>
> >> There is virtually no FLARM in the US. *It is unlikely to take off here,
> >> as the biggest threats for mid-airs in the US are between powered
> >> aircraft and gliders or other aircraft.
>
> >> It's a chicken and egg situation. *FLARM is only interesting if everyone
> >> equips. *No one is going to equip if they don't think that everyone else
> >> will.
>
> >> With ADS-B coming out, that is the way to go in the US. *If you buy an
> >> ADS-B transceiver, not only will you see other ADS-B equipped aircraft,
> >> but, if you are within range of an ADS-B ground station, you will also
> >> see all Mode C/S transponder equipped aircraft that are visible to ATC..
> >> * *With 80-90% of GA aircraft in the US transponder equipped, this gives
> >> an immediate benefit to anyone investing in ADS-B (assuming that they
> >> have a ground station deployed in their area).
>
> >> --
> >> Mike Schumann
>
> > Mike,
> > Your points are all well taken. I realize that FLARM has never been
> > accepted in the US up to now, and we all know that ADS-B is coming in
> > 2020 (although I thought there was a "glider" exemption), but with
> > that being said, would it make any sense for FLARM units to be
> > required for gliders competing in any of our nationals (or maybe even
> > in regionals)?
>
> > As you are aware, we've had several mid-airs between gliders in recent
> > years and perhaps if gliders had been equipped with FLARM units in a
> > nationals or in a regionals, some of these mid-airs might have been
> > prevented.....Just a thought!
>
> > Thanks - Renny
>
> Why not require ADS-B units instead. *Then you'd get the advantages of
> FLARM, but you'd also see all of the transponder equipped GA aircraft
> (assuming that there was a ground station in the area).
>
> Now that Navworx is shipping their unit, this could happen tomorrow.
> I'm sure that someone could talk Navworx into working with the major
> glide computer manufacturers to provide the necessary interfaces if they
> knew that this would be worth their while.
>
> --
> Mike Schumann

Mike

You are back again proposing the same NavWorx ADS-B transceiver for
glider cockpits that was discussed recently and just does not look
practical for our needs. While I'd love to see products that do meet
our needs, unfortunately there are currently no available UAT
transceivers that do appear suitable for use in gliders and none that
I am aware of that are coming in the near term that will change this.
Anybody able to share any different information?

So I'll repeat below again the issues with the NavWorx ADS600-B. Until
an ADS-B transceiver addresses these issues I don't see how it can
hope to have any wide adoption in glider cockpits.

---

1. The specified 0.8 Amp (scaled to @12V) power draw the Navworx
ADS600-B ADS-B transceiver is just too much to be interesting for most
glider cockpits. Do you have different information on the actual power
draw? This is the receiver box alone and today a display would need to
be added increasing this power consumption.

2. (A) The NavWorx does not support the FLARM serial display protocol
so is not compatible with most current PDA/PNA soaring software and
flight computers (e.g. the ClearNav) that all support the FLARM
display protocol. Navworx could implement this, and I've talked to
them about this, but it does not seem to be something they are
interested in doing now. With a current device with power consumption
that just does not fit what we need it would not seem to make business
sense for them to target delivering a glider specific display
protocol. It might make more sense combined with a future lower-power
consumption version of their devices. Given they are a small company
and just have their first transceiver going into the market I'd not
hold my breath. Their transceiver will likely be interesting for the
lower-end of the GA market who have older panels with Mode C
transponders and who do not have a Mode S transponder upgradable to
1090ES data-out, they really need TSO approval for the product to be
successful in the GA market and I kind of expect that is where their
resources are focused.

2 (B) The NavWorx and many other ADS-B receivers has no built-in
traffic warning or traffic filtering algorithms so won't itself warn
about traffic. It relies on the external display system to do this.
None of these systems available are tuned for gliders, i.e. provide
the type of threat detection and false alarm prevention required in
many glider situations, especially when thermalling in gaggles (likely
one of the contest scenarios worrying many people). And it is not just
a matter of working to connect the ADS-B box to existing gliding
software or flight computers. Those systems today support the Flarm
serial protocol - in this scheme the traffic threat processing is done
within the Flarm (or PowerFLARM) box, with a NavWorx receiver
connected that gliding software or flight computer will need to do the
threat assessment and false alarm prevention etc. itself. Having said
that I believe some of these soaring software and flight computer
vendors should be working to support basic display of ADS-B traffic
(and FIS-B weather etc.) -- this may make sense for example where ADS-
B is being used as an adjunct to a transponder in busy GA traffic
areas. I've actively tried to encourage some of those ADS-B and
soaring products vendors to play together for this reason. However I'm
just not sure those vendors would want to step up and do the FLARM
style traffic threat detection. Especially since most of their market
that cares about traffic warning is already using Flarm.

2 (C) The Flarm serial display protocol combines aircraft GPS location
and traffic data into a single serial stream so that one serial port
on a PDA or flight computer can receive both data. Other popular
display protocol used for ADS-B traffic display like the Garmin TIS
protocol does not do this and would require a separate serial port for
GPS position data and for traffic data or some external third party
hardware box to combine two serial ports. This won't be an issue for
everybody but I suspect will be a problem for a significant number of
pilots. Just adding support in the PDA or flight computer software for
one of these other display protocols does not change this problem. You
really need the ADS-B receiver product to support the Flarm serial
display protocol for the product to be easily usable in a wide range
of glider cockpits.

3. Cost. At US$2,495 list the NavWorx ADS600-B ADS-B transceiver is
significantly more expensive than a PowerFlarm (~$US1,695 list) by
itself (for it's Flarm to Flarm capability). When you factor in costs
of a display for the ADS-B and other components it is in the ball park
of say a PowerFLARM + Trig TT21 which can do ADS-B data-out. The TT-21
with 1090ES data or out or a similar 1090ES transponder, or even a UAT
transmitter, is required to have the PowerFLARM ADS-B receiver work
properly in the USA. (And technically unless you want to add a
currently expensive GPS receiver the TT21 cannot meet the 2020
mandatory ADS-B data-out requirements, but neither will the currently
non-TSO ADS600-B, but lucky we don't need to meet those requirements
for gliders). I think current ADS-B prices for an actual working
system of around $3k and more price it out of most glider cockpits
even if it actually did what was needed to help with the glider-on-
glider threat. While prices may fall over time I'd not hold my breath
for a radical reduction, I suspect current vendors are meeting early
adopter needs in the GA market and there won't be a lot of movement on
pricing until we get closer to 2020.

---

The Mitre UAT transceiver prototype while it should have low power
consumption compared to the Navworx ADS600-B it is just a prototype
and AFAIK has the other problems described above. I am happy seeing an
R&D platform and prototype device being developed and hopefully used
to work on issues relevant to ADS-B in gliders but it is a long way
from that to something Mitre or others can convince a manufacture to
want to make (effectively for the USA gliding community only, yikes
that's a small market) and then to something we can buy. And I'm not
really sure Mitre or anybody else are addressing the needs or the
glider cockpit. If they were the prototype would already have things
like serial FLARM support and threat assessment etc. handled on-board.
That is just such an obvious requirement for the gilder market.

Darryl

Steve Koerner

August 9th 10, 07:03 PM

Andy is exactly right. The big deal that is Flarm is not the
hardware and the radio signal mechanisms it is the algorithms and the
decision logic that is responding to the air interface. I would be
willing to bet that the Flarm folks have put 90% of their engineering
efforts on refining and perfecting the response logic as compared to
10% for all the rest of the design. In the US we are extremely
fortunate that this work has already been done. There has been years
of refinement effort that has been done specifically for soaring. An
ADS-B unit primarily designed for power planes (as they all are) will
not be satisfactory for glider - glider protection.

In my view, the new PowerFlarm unit is a brilliant solution to the
problem. It allows US pilots to piggy-back the tremendous amount of
effort expended to perfect Flarm in Europe. It provides the PCAS type
function to help protect against putt-putt traffic and it also
provides the ADS-B receive technology so that it can be used as a big
chunk of the ADS-B solution as that becomes more widely adopted in the
out years.

We must adopt PowerFlarm technology for the 2011 racing season in the
US. There is no chicken and egg problem when it is a requirement for
entry in all sanctioned contests. I plead for support from every
racing pilot on this. There was a midair at the last two contests
that I attended. There has also been a midair at the last two
contests that I attended at Uvalde. The crash at Uvlade last week
was highly disconcerting to me. Chris was a great guy. Even though
I was doing well in the contest, I just went home. I was intending
not to return to the sport ever again. If we can make racing safer
with rule and procedure changes and with immediate adoption of Power
Flarm, I hope that I will be able to change my mind.

rhwoody

August 9th 10, 07:07 PM

On Aug 9, 11:29*am, Mike Schumann >
wrote:
> On 8/9/2010 11:57 AM, Andy wrote:
>
>
>
> > On Aug 9, 9:45 am, Mike >
> > wrote:
>
> >> Why not require ADS-B units instead. *Then you'd get the advantages of
> >> FLARM, but you'd also see all of the transponder equipped GA aircraft
> >> (assuming that there was a ground station in the area).
>
> > Perhaps because glider pilots would be overwhelmed by nuissance alerts
> > when contest flying? *I have already experienced my PCAS becoming
> > close to useless as more gliders are fitted with transponders. *I
> > don't need another system crying wolf all the time.
>
> > FLARM uses intelligent alerting based on glider flight
> > characteristics. *It has been reported that the nuissance alerting
> > frequency low enough that it is still useful in high glider traffic
> > densities.
>
> > Andy
>
> There are two parts to FLARM; *an ADS-B type position reporting
> broadcast function, and a built in collision warning system.
>
> ADS-B transceivers typically do not include any collision warning logic.
> * Instead they are more like modems. *They transmit and receive position
> data in addition to receiving weather info, etc. *This information is
> passed on to some form of graphics display device so that the locations
> of other aircraft can be shown on a moving map display relative to your
> own aircraft.
>
> The display device, in addition to showing the location of other
> aircraft, can also be programmed to provide collision warnings.
> Obviously, the typical flight trajectories of gliders are different than
> most power aircraft. *I suspect that most glider specific moving map
> vendors will try to match FLARM's logic to minimize false alarms if they
> elect to provide a collision warning function in addition to just
> displaying the relative locations of other aircraft.
>
> ADS-B is obviously just in its infancy in the US vs FLARM's development
> in Europe. *The encouraging news is that the potential size of the US
> ADS-B market is much larger than the potential FLARM market in Europe
> (when you include the GA power market), so there will undoubtedly be
> lots of innovation in the display devices that will provide the
> collision warning function. *In VFR environments, these devices will not
> require FAA approvals, so I expect that technical advancements will be
> very rapid, once low cost ADS-B transceivers become widely available.
>
> --
> Mike Schumann- Hide quoted text -
>
> - Show quoted text -

I have Flarm in my glider - have had it for 2 years plus - I fly in
Namibia
where it is mandatory - when coupled with the Butterfly and the Blue
Box it shows all transponders plus the Flarm targets - and the
Butterfly
shows multiple targets within the pilot entered radius - plus it shows
the
climb rate of the various targets - this function is outlawed in
European
competitions - only that function - the rest works as usual -
Flarm works great and is a huge safety instrument - but it only works
if everyone has it - the stray who doesn't have it is a risk -
my personal opinion is that Flarm was mandatory for all gliders in the
15m
Nationals at Uvalde there would not have been a mid-air - and if task
setters
would not set tasks with opposing traffic it would also help a lot -
in my opinion the US competition scene will eventually make it
mandatory
to have Flarm or similar - in the very near future - the Flarm is not
an
expensive instrument - and remember that funerals and estate
settlements
are very, very expensive - hospitals as well -
just my $0.02 worth
locally I use the Zaon to see the jet and power traffic that can run
you
down from behind -

Darryl Ramm

August 9th 10, 07:14 PM

On Aug 9, 10:29*am, Mike Schumann >
wrote:
> On 8/9/2010 11:57 AM, Andy wrote:
>
> > On Aug 9, 9:45 am, Mike >
> > wrote:
>
> >> Why not require ADS-B units instead. *Then you'd get the advantages of
> >> FLARM, but you'd also see all of the transponder equipped GA aircraft
> >> (assuming that there was a ground station in the area).
>
> > Perhaps because glider pilots would be overwhelmed by nuissance alerts
> > when contest flying? *I have already experienced my PCAS becoming
> > close to useless as more gliders are fitted with transponders. *I
> > don't need another system crying wolf all the time.
>
> > FLARM uses intelligent alerting based on glider flight
> > characteristics. *It has been reported that the nuissance alerting
> > frequency low enough that it is still useful in high glider traffic
> > densities.
>
> > Andy
>
> There are two parts to FLARM; *an ADS-B type position reporting
> broadcast function, and a built in collision warning system.
>
> ADS-B transceivers typically do not include any collision warning logic.
> * Instead they are more like modems. *They transmit and receive position
> data in addition to receiving weather info, etc. *This information is
> passed on to some form of graphics display device so that the locations
> of other aircraft can be shown on a moving map display relative to your
> own aircraft.
>
> The display device, in addition to showing the location of other
> aircraft, can also be programmed to provide collision warnings.
> Obviously, the typical flight trajectories of gliders are different than
> most power aircraft. *I suspect that most glider specific moving map
> vendors will try to match FLARM's logic to minimize false alarms if they
> elect to provide a collision warning function in addition to just
> displaying the relative locations of other aircraft.
>
> ADS-B is obviously just in its infancy in the US vs FLARM's development
> in Europe. *The encouraging news is that the potential size of the US
> ADS-B market is much larger than the potential FLARM market in Europe
> (when you include the GA power market), so there will undoubtedly be
> lots of innovation in the display devices that will provide the
> collision warning function. *In VFR environments, these devices will not
> require FAA approvals, so I expect that technical advancements will be
> very rapid, once low cost ADS-B transceivers become widely available.
>
> --
> Mike Schumann

Andy raises a specific good point, that there is no current answer to,
except hand waving and hoping. So to be clear, there is no ADS-B
product (besides the soon to be PowerFLARM 1090ES receiver) that is
optimized for glider threats/traffic warning. None. Nada. Zilch. And I
expect false alarms to be a significant issues with current ADS-B
systems especially in busy gaggles - one of the times that many glider
pilots worried about glider-on-glider threats may be most interested
in usable collision avoidance warnings.

Until we have an ADS-B products specifically targeted at the needs of
glider cockpits they are unlikely to successful in this market for all
the reasons I've pointed out elsewhere in this thread. Glider pilots
worrying about glider-on-glider and glider-on-towplane type collision
scenarios may not be that well served with a traffic display/warning
system developed for GA aircraft, especially in contest scenarios. It
will likely have all the false alarm issues Andy is raising. Somebody
with a focus on delivering a product to the glider community has to
develop that system, whether (ideally, for reasons pointed out
elsewhere in this thread) it is within the ADS-B transceiver/receiver
product or within an external display product. Then your claims about
market sizing and innovation just flip on their head. The potential
size of the USA market for people who want ADS-B transceivers/
receivers in their glider cockpits is smaller than the size of the
existing worldwide (not just Europe) Flarm market.

Darryl

Mike Schumann

August 9th 10, 07:22 PM

On 8/9/2010 12:55 PM, Darryl Ramm wrote:
> On Aug 9, 9:45 am, Mike >
> wrote:
>> On 8/9/2010 9:12 AM, Renny wrote:
>>
>>> On Aug 9, 7:56 am, Mike >
>>> wrote:
>>>> On 8/9/2010 8:43 AM, Steve Freeman wrote:
>>
>>>>> Curious about the use of Flarm in the US. Was told by another pilot
>>>>> that the frequency used by Flarm is not approved for that category of
>>>>> use in the US. Is that true? If it is, do they make units that use a
>>>>> US approved frequency?
>>
>>>> There is virtually no FLARM in the US. It is unlikely to take off here,
>>>> as the biggest threats for mid-airs in the US are between powered
>>>> aircraft and gliders or other aircraft.
>>
>>>> It's a chicken and egg situation. FLARM is only interesting if everyone
>>>> equips. No one is going to equip if they don't think that everyone else
>>>> will.
>>
>>>> With ADS-B coming out, that is the way to go in the US. If you buy an
>>>> ADS-B transceiver, not only will you see other ADS-B equipped aircraft,
>>>> but, if you are within range of an ADS-B ground station, you will also
>>>> see all Mode C/S transponder equipped aircraft that are visible to ATC.
>>>> With 80-90% of GA aircraft in the US transponder equipped, this gives
>>>> an immediate benefit to anyone investing in ADS-B (assuming that they
>>>> have a ground station deployed in their area).
>>
>>>> --
>>>> Mike Schumann
>>
>>> Mike,
>>> Your points are all well taken. I realize that FLARM has never been
>>> accepted in the US up to now, and we all know that ADS-B is coming in
>>> 2020 (although I thought there was a "glider" exemption), but with
>>> that being said, would it make any sense for FLARM units to be
>>> required for gliders competing in any of our nationals (or maybe even
>>> in regionals)?
>>
>>> As you are aware, we've had several mid-airs between gliders in recent
>>> years and perhaps if gliders had been equipped with FLARM units in a
>>> nationals or in a regionals, some of these mid-airs might have been
>>> prevented.....Just a thought!
>>
>>> Thanks - Renny
>>
>> Why not require ADS-B units instead. Then you'd get the advantages of
>> FLARM, but you'd also see all of the transponder equipped GA aircraft
>> (assuming that there was a ground station in the area).
>>
>> Now that Navworx is shipping their unit, this could happen tomorrow.
>> I'm sure that someone could talk Navworx into working with the major
>> glide computer manufacturers to provide the necessary interfaces if they
>> knew that this would be worth their while.
>>
>> --
>> Mike Schumann
>
> Mike
>
> You are back again proposing the same NavWorx ADS-B transceiver for
> glider cockpits that was discussed recently and just does not look
> practical for our needs. While I'd love to see products that do meet
> our needs, unfortunately there are currently no available UAT
> transceivers that do appear suitable for use in gliders and none that
> I am aware of that are coming in the near term that will change this.
> Anybody able to share any different information?
>
> So I'll repeat below again the issues with the NavWorx ADS600-B. Until
> an ADS-B transceiver addresses these issues I don't see how it can
> hope to have any wide adoption in glider cockpits.
>
> ---
>
> 1. The specified 0.8 Amp (scaled to @12V) power draw the Navworx
> ADS600-B ADS-B transceiver is just too much to be interesting for most
> glider cockpits. Do you have different information on the actual power
> draw? This is the receiver box alone and today a display would need to
> be added increasing this power consumption.
>
> 2. (A) The NavWorx does not support the FLARM serial display protocol
> so is not compatible with most current PDA/PNA soaring software and
> flight computers (e.g. the ClearNav) that all support the FLARM
> display protocol. Navworx could implement this, and I've talked to
> them about this, but it does not seem to be something they are
> interested in doing now. With a current device with power consumption
> that just does not fit what we need it would not seem to make business
> sense for them to target delivering a glider specific display
> protocol. It might make more sense combined with a future lower-power
> consumption version of their devices. Given they are a small company
> and just have their first transceiver going into the market I'd not
> hold my breath. Their transceiver will likely be interesting for the
> lower-end of the GA market who have older panels with Mode C
> transponders and who do not have a Mode S transponder upgradable to
> 1090ES data-out, they really need TSO approval for the product to be
> successful in the GA market and I kind of expect that is where their
> resources are focused.
>
> 2 (B) The NavWorx and many other ADS-B receivers has no built-in
> traffic warning or traffic filtering algorithms so won't itself warn
> about traffic. It relies on the external display system to do this.
> None of these systems available are tuned for gliders, i.e. provide
> the type of threat detection and false alarm prevention required in
> many glider situations, especially when thermalling in gaggles (likely
> one of the contest scenarios worrying many people). And it is not just
> a matter of working to connect the ADS-B box to existing gliding
> software or flight computers. Those systems today support the Flarm
> serial protocol - in this scheme the traffic threat processing is done
> within the Flarm (or PowerFLARM) box, with a NavWorx receiver
> connected that gliding software or flight computer will need to do the
> threat assessment and false alarm prevention etc. itself. Having said
> that I believe some of these soaring software and flight computer
> vendors should be working to support basic display of ADS-B traffic
> (and FIS-B weather etc.) -- this may make sense for example where ADS-
> B is being used as an adjunct to a transponder in busy GA traffic
> areas. I've actively tried to encourage some of those ADS-B and
> soaring products vendors to play together for this reason. However I'm
> just not sure those vendors would want to step up and do the FLARM
> style traffic threat detection. Especially since most of their market
> that cares about traffic warning is already using Flarm.
>
> 2 (C) The Flarm serial display protocol combines aircraft GPS location
> and traffic data into a single serial stream so that one serial port
> on a PDA or flight computer can receive both data. Other popular
> display protocol used for ADS-B traffic display like the Garmin TIS
> protocol does not do this and would require a separate serial port for
> GPS position data and for traffic data or some external third party
> hardware box to combine two serial ports. This won't be an issue for
> everybody but I suspect will be a problem for a significant number of
> pilots. Just adding support in the PDA or flight computer software for
> one of these other display protocols does not change this problem. You
> really need the ADS-B receiver product to support the Flarm serial
> display protocol for the product to be easily usable in a wide range
> of glider cockpits.
>
> 3. Cost. At US$2,495 list the NavWorx ADS600-B ADS-B transceiver is
> significantly more expensive than a PowerFlarm (~$US1,695 list) by
> itself (for it's Flarm to Flarm capability). When you factor in costs
> of a display for the ADS-B and other components it is in the ball park
> of say a PowerFLARM + Trig TT21 which can do ADS-B data-out. The TT-21
> with 1090ES data or out or a similar 1090ES transponder, or even a UAT
> transmitter, is required to have the PowerFLARM ADS-B receiver work
> properly in the USA. (And technically unless you want to add a
> currently expensive GPS receiver the TT21 cannot meet the 2020
> mandatory ADS-B data-out requirements, but neither will the currently
> non-TSO ADS600-B, but lucky we don't need to meet those requirements
> for gliders). I think current ADS-B prices for an actual working
> system of around $3k and more price it out of most glider cockpits
> even if it actually did what was needed to help with the glider-on-
> glider threat. While prices may fall over time I'd not hold my breath
> for a radical reduction, I suspect current vendors are meeting early
> adopter needs in the GA market and there won't be a lot of movement on
> pricing until we get closer to 2020.
>
> ---
>
> The Mitre UAT transceiver prototype while it should have low power
> consumption compared to the Navworx ADS600-B it is just a prototype
> and AFAIK has the other problems described above. I am happy seeing an
> R&D platform and prototype device being developed and hopefully used
> to work on issues relevant to ADS-B in gliders but it is a long way
> from that to something Mitre or others can convince a manufacture to
> want to make (effectively for the USA gliding community only, yikes
> that's a small market) and then to something we can buy. And I'm not
> really sure Mitre or anybody else are addressing the needs or the
> glider cockpit. If they were the prototype would already have things
> like serial FLARM support and threat assessment etc. handled on-board.
> That is just such an obvious requirement for the gilder market.
>
> Darryl
>
>

We currently already have a Rube Goldberg ADS-B strategy in the US where
we have two competing flavors of ADS-B, no strategy to get rid of
conventional transponders, and now we've got somebody advocating adding
FLARM to the mix for a VERY small subset of aircraft population. This
is going to solve all of our problems?????

The only long term solution is to get everyone (gliders, GA, airliners,
balloons, parachutists, UAVs, etc.....) to standardize on a single
collision avoidance technology. We had the golden opportunity to do
that with ADS-B UAT, but the FAA has totally screwed that up, and now
everyone is going off into a thousand different directions.

The FLARM guys didn't help either. Years ago, when FLARM 1st came out,
they specifically prohibited the use of their equipment in the US. If
they hadn't done that, maybe FLARM would have taken off here in parallel
with Europe and become a defacto standard for the GA community.

They also could have taken their hardware platform and come out with a
US version that conformed to the ADS-B UAT frequency and protocol
standards. For whatever reason, they weren't interested in that either.

Maybe the best solution is for the SSA to buy 50 basic FLARM boxes and
rent them out to contests to use in the short term and wait for the FAA
and the market to sort things out over the next 20 years.

My suggestion is to forget about contests and use OLC if you need a fix
for your competitive urges.

--
Mike Schumann

noel.wade

August 9th 10, 07:23 PM

On Aug 9, 10:55*am, Darryl Ramm > wrote:

> significantly more expensive than a PowerFlarm (~$US1,695 list) by
> itself (for it's Flarm to Flarm capability). When you factor in costs

Darryl - Where are you getting this price? The websites I see list
1500 to 1600 EUROS. By the time you add mounting hardware, shipping,
etc you're looking at $2200 - $2500 (not including installation if you
want that done by an A&P).

-----
On a separate note: Some PDA software (like the LK8000) and "glass
cockpit" displays already have some built-in support for FLARM anti-
collision display & warnings... Has there been talk about a
powerFLARM unit that is "headless" (i.e. has no display but simply
plugs into PDA or Craggy Ultimate or NK ClearNav or LX devices)?? I
would think that omitting the display would save on cost & power
consumption, as well as allowing the unit to be mounted in more places
in the aircraft (instead of cluttering up crowded instrument panels or
impacting the pilot's forward visibility).

Anyone hear any murmurs of this?

--Noel

John Smith

August 9th 10, 07:50 PM

Mike Schumann wrote:
> The FLARM guys didn't help either. Years ago, when FLARM 1st came out,
> they specifically prohibited the use of their equipment in the US.

They did not only prohibit the use of FLARM in the USA, but also in
gliders with a US citizen on board. Guess why.

Side note: Please trim the messages you're answering to to a reasonable
size!

brianDG303[_2_]

August 9th 10, 08:02 PM

Darryl Ramm

August 9th 10, 08:12 PM

On Aug 9, 11:23*am, "noel.wade" > wrote:
> On Aug 9, 10:55*am, Darryl Ramm > wrote:
>
> > significantly more expensive than a PowerFlarm (~$US1,695 list) by
> > itself (for it's Flarm to Flarm capability). When you factor in costs
>
> Darryl - Where are you getting this price? *The websites I see list
> 1500 to 1600 EUROS. *By the time you add mounting hardware, shipping,
> etc you're looking at $2200 - $2500 (not including installation if you
> want that done by an A&P).
>
> -----
> On a separate note: *Some PDA software (like the LK8000) and "glass
> cockpit" displays already have some built-in support for FLARM anti-
> collision display & warnings... *Has there been talk about a
> powerFLARM unit that is "headless" (i.e. has no display but simply
> plugs into PDA or Craggy Ultimate or NK ClearNav or LX devices)?? *I
> would think that omitting the display would save on cost & power
> consumption, as well as allowing the unit to be mounted in more places
> in the aircraft (instead of cluttering up crowded instrument panels or
> impacting the pilot's forward visibility).
>
> Anyone hear any murmurs of this?
>
> --Noel

Yo Noel

The pricing I gave is the latest I have from the US Distributor. AFAIK
resellers will include the usual bunch, Cumulus Soaring, Wings and
Wheels, Williams Soaring, Craggy Aero and others. A quick check shows
the page at Craggy Aero http://www.craggyaero.com/powerflarm.htm.
(Sorry Paul, Tim, Rex, et al. if you have this on your site I could
not find it). Those resellers may be holding off advertising the unit
until it is actually shipping. I know some of them have been taking
pre-orders.

The XCSoar software on which LK8000 is based also supports the Flarm
serial display protocol. I'm not aware of what specifically LK8000 has
changed but I just wanted to point out it is a basic capability in
XCSoar... and most other popular soaring software and many flight
computers today... SeeYou Mobile, Winpilot, SN-10, ClearNav, LX flight
computers, etc. etc. etc.

A headless device would seem to make sense.

BTW the PowerFLARM display is pretty compact, and uses an OLED cell
phone type display so don't necessarily assume a huge reduction in
power consumption by removing the display. BTW one good way to
visualize the size of a PowerFLARM is it is basically the size of two
Zaon MRX PCAS units sitting on top of each other.

Hope that helps.

Darryl

Darryl Ramm

August 9th 10, 08:30 PM

On Aug 9, 9:48*am, Mike Schumann >
wrote:
> On 8/9/2010 11:23 AM, brianDG303 wrote:
>
>
>
> > On Aug 9, 7:12 am, > *wrote:
> >> On Aug 9, 7:56 am, Mike >
> >> wrote:
>
> >>> On 8/9/2010 8:43 AM, Steve Freeman wrote:
>
> >>>> Curious about the use of Flarm in the US. Was told by another pilot
> >>>> that the frequency used by Flarm is not approved for that category of
> >>>> use in the US. Is that true? If it is, do they make units that use a
> >>>> US approved frequency?
>
> >>> There is virtually no FLARM in the US. *It is unlikely to take off here,
> >>> as the biggest threats for mid-airs in the US are between powered
> >>> aircraft and gliders or other aircraft.
>
> >>> It's a chicken and egg situation. *FLARM is only interesting if everyone
> >>> equips. *No one is going to equip if they don't think that everyone else
> >>> will.
>
> >>> With ADS-B coming out, that is the way to go in the US. *If you buy an
> >>> ADS-B transceiver, not only will you see other ADS-B equipped aircraft,
> >>> but, if you are within range of an ADS-B ground station, you will also
> >>> see all Mode C/S transponder equipped aircraft that are visible to ATC.
> >>> * *With 80-90% of GA aircraft in the US transponder equipped, this gives
> >>> an immediate benefit to anyone investing in ADS-B (assuming that they
> >>> have a ground station deployed in their area).
>
> >>> --
> >>> Mike Schumann
>
> >> Mike,
> >> Your points are all well taken. I realize that FLARM has never been
> >> accepted in the US up to now, and we all know that ADS-B is coming in
> >> 2020 (although I thought there was a "glider" exemption), but with
> >> that being said, would it make any sense for FLARM units to be
> >> required for gliders competing in any of our nationals (or maybe even
> >> in regionals)?
>
> >> As you are aware, we've had several mid-airs between gliders in recent
> >> years and perhaps if gliders had been equipped with FLARM units in a
> >> nationals or in a regionals, some of these mid-airs might have been
> >> prevented.....Just a thought!
>
> >> Thanks - Renny
>
> > Mike and Renny,
> > a good discussion of the macro view of FLARM and ADS-B. Another view
> > is more personal, for example in my situation- I fly a lot of ridge
> > and mountain in a very narrow altitude band and a lot of clouds. There
> > is not a lot of power traffic in those conditions. I have a
> > transponder but I don't see the Transmit light going off very often
> > and I suspect I am not getting very many radar paints down in the
> > rocks and trees where I like to fly. My greatest risk is from the six
> > other gliders I share the area with, which do not have transponders
> > and will never get them at the current costs; in fairness my threat to
> > them is even higher as I am a low hour pilot. FLARM would go a long
> > way to reducing the risks and at a reasonable cost; PowerFlarm would
> > be my choice as it would also provide protection from ADS-B and
> > transponder equipped threats, but at twice the cost the installed base
> > in my situation would be very much reduced and I stand a better chance
> > of talking my potentially deadly friends into investing in FLARM. 2020
> > is not soon enough. It is not soon enough for the pilots killed on a
> > regular basis at contests, which we seem to simply accept as an
> > unavoidable risk.
>
> > With that in mind Mike's statement that FLARM isn't of use (for me)
> > would not be correct. In 2004 my club lost two gliders and a pilot in
> > a collision that would not have happens if they had had FLARM. How do
> > you calculate that cost?
>
> > Brian
>
> Why not convince your fellow pilots to invest in the Navworx ADS-B
> transceiver that is now shipping? *FLARM in the US is a dead end. *ADS-B
> is the future. *If you invest in a Navworx type of device, not only
> would you see each other, but you will also see other ADS-B equipped GA
> aircraft, and if you are flying within range of a ground station, ALL
> transponder equipped aircraft.
>
> --
> Mike Schumann

Ah maybe becasue they draw 0.8 amps, cost $2,495 each, don't warn
about traffic threats themselves, and are not compatible with any
traffic display systems used in glider cockpits. Besides those minor
little inconveniences your suggestion to buy this specific ADS-B UAT
transceiver is wonderful.

---

Anyhow back to the factual stuff... Flarm in the USA is not a dead-
end. Flarm in the USA has been at a dead-end and that is about to
change. There has been no Flarm product in the USA, that is changing
with the import of the PowerFLARM device. The folks behind Flarm and
it's importers have specifically focused on delivering the PowerFLARM
product to the USA market that combines all the capabilities and
compatibility of FLARM with an ADS-B 1090ES traffic receiver.
PowerFLARM seems a very smart way for piltos to adopt FLARM today and
then move towards an ADS-B future.

Folks who've seen my ADS-B talks at PASCO seminars etc. will know I am
concerned about the adoption of Flarm devices. Concerned that people
invest in a Flarm protocol only device and then put off any ADS-B
future. Or that islands of Flarm adoption occur in some places, ADS-B
in others etc. and then in many years time we end up with
geographically/regionally fragmented adoption. I'm also concerned that
all these devices, especially anything ADS-B, is too complex for many
pilots to understand and I don't want to see pilots say buying an ADS-
B transceiver or a Flarm device thinking that is all they need for any
traffic scenario, or that it will make them visible to airliner TCAS,
etc. For these reasons I think the adoption of the PowerFLARM device
*with* 1090ES receiver capability and not a Flarm only device is the
correct way to go for the USA market.

Anecdotally there is really nobody I know who is seriously working on
installing pure ADS-B in gliders in the short term, however I know
several pilots who have already pre-ordered their PowerFLARM and
several clubs and FBOs thinking about fleet wide adoption. The serious
ADS-B "geeks" I know who are currently or wanting to run ADS-B data-
out with their Trig TT-21 seem to be mostly interested in doing so for
future use with a PowerFLARM ADS-B receiver.

To operate as an ADS-B traffic in the USA the glider will need an ADS-
B transmitter, as owners of a PowerFLARM want to do this they will
need to add a Mode S 1090ES transponder or upgrade their current Mode
S transponder or add a UAT transmitter or transceiver. If really low
cost GA targeted ADS-B transceivers do appear it may still make most
sense to just use the UAT transmitter part of that transceiver to send
the ADS-B location and to use the 1090ES receiver in the PowerFLARM
since it does the FLARM glider tuned traffic threat analysis, is
compatible with current glider cockpit displays etc. So to my mind
buying a PowerFLARM i the opposite to a dead-end, to me it is the
*only* viable ADS-B glider traffic receiver product on the market, and
you get a full FLARM-FLARM protocol device as well. Unless something
radical happens that I do not see, I expect PowerFLARM to be the most
common product over the next several years through which some early
adopter glider pilots will receive ADS-B traffic data in the USA. But
currently pricing for a full ADS-B system will keep those wanting to
use ADS-B down to early/bleeding edge adopters.

---

We seem to be focused here on glider-on-glider threats, I just want to
remind people that near dense airline and fast jet traffic a
transponder today is the only technology that provides both visibility
to ATC and compatibility with the TCAS systems carried by most those
airliners and jets. TCAS does not detect UAT ADS-B transmitters but
will see 1090ES transmitters (it sees the transponder). We need to be
really careful in promoting any technology as to what exact problem it
is good at solving. Remember the answer is 42, now if we could just
work out the question.

ADS-B has potential benefits such as long range tracking for SAR and
maybe contest tracking etc., precision "visibility" of/to GA aircraft
esp. outside current radar coverage, some long-range augmentation to
TCAS for visibility of gliders to airliners and fast jets etc. as
those aircraft deploy combined CDTI and TCAS systems etc. but by
itself it falls short at the two extremes of glider-on-glider
scenarios and airline-on-glider scenarios, yet these are the two
scenarios that ADS-B is often thought about for use in gliders. We
need to consider the appropriate use of Flarm, transponders (and PCAS
etc.) and ADS-B. No single one of these technologies really
effectively help addresses/minimize collisions threats through the
entire gamut of glider-on-glider through glider-on-GA to glider-on-
airliner and fast jet scenarios.

Darryl

noel.wade

August 9th 10, 08:31 PM

Darryl & Brian -

Thanks for the corrections on pricing. Under $2k starts making it
very attractive.

Regarding the headless bit: Its not just about power, its also
installation location. DG instrument panels/pods are great for
ergonomics and bailout ability, but they don't have a lot of extra
space for stuff like this. I already have my ewMicroRecorder on top
of the instrument pod and don't want to block my forward view. A
headless unit would allow me to install it under the seat-pan or
behind my head, and a hookup to my PDA or a flight computer would
still provide visual (and hopefully audible) cues when there was a
collision risk.

Regarding XCSoar: I haven't used XCSoar in over a year and couldn't
remember for sure to what degree it supported FLARM. In LK8000 the
FLARM support has been re-written and is much more fully-featured.
Bottom-line: the more devices that support it, the better!

--Noel

bildan

August 9th 10, 08:46 PM

On Aug 9, 12:07*pm, rhwoody > wrote:
> On Aug 9, 11:29*am, Mike Schumann >
> wrote:
>
>
>
> > On 8/9/2010 11:57 AM, Andy wrote:
>
> > > On Aug 9, 9:45 am, Mike >
> > > wrote:
>
> > >> Why not require ADS-B units instead. *Then you'd get the advantages of
> > >> FLARM, but you'd also see all of the transponder equipped GA aircraft
> > >> (assuming that there was a ground station in the area).
>
> > > Perhaps because glider pilots would be overwhelmed by nuissance alerts
> > > when contest flying? *I have already experienced my PCAS becoming
> > > close to useless as more gliders are fitted with transponders. *I
> > > don't need another system crying wolf all the time.
>
> > > FLARM uses intelligent alerting based on glider flight
> > > characteristics. *It has been reported that the nuissance alerting
> > > frequency low enough that it is still useful in high glider traffic
> > > densities.
>
> > > Andy
>
> > There are two parts to FLARM; *an ADS-B type position reporting
> > broadcast function, and a built in collision warning system.
>
> > ADS-B transceivers typically do not include any collision warning logic..
> > * Instead they are more like modems. *They transmit and receive position
> > data in addition to receiving weather info, etc. *This information is
> > passed on to some form of graphics display device so that the locations
> > of other aircraft can be shown on a moving map display relative to your
> > own aircraft.
>
> > The display device, in addition to showing the location of other
> > aircraft, can also be programmed to provide collision warnings.
> > Obviously, the typical flight trajectories of gliders are different than
> > most power aircraft. *I suspect that most glider specific moving map
> > vendors will try to match FLARM's logic to minimize false alarms if they
> > elect to provide a collision warning function in addition to just
> > displaying the relative locations of other aircraft.
>
> > ADS-B is obviously just in its infancy in the US vs FLARM's development
> > in Europe. *The encouraging news is that the potential size of the US
> > ADS-B market is much larger than the potential FLARM market in Europe
> > (when you include the GA power market), so there will undoubtedly be
> > lots of innovation in the display devices that will provide the
> > collision warning function. *In VFR environments, these devices will not
> > require FAA approvals, so I expect that technical advancements will be
> > very rapid, once low cost ADS-B transceivers become widely available.
>
> > --
> > Mike Schumann- Hide quoted text -
>
> > - Show quoted text -
>
> I have Flarm in my glider - have had it for 2 years plus - I fly in
> Namibia
> where it is mandatory - when coupled with the Butterfly and the Blue
> Box it shows all transponders plus the Flarm targets - and the
> Butterfly
> shows multiple targets within the pilot entered radius - plus it shows
> the
> climb rate of the various targets - this function is outlawed in
> European
> competitions - only that function - the rest works as usual -
> Flarm works great and is a huge safety instrument - but it only works
> if everyone has it - the stray who doesn't have it is a risk -
> my personal opinion is that Flarm was mandatory for all gliders in the
> 15m
> Nationals at Uvalde there would not have been a mid-air - and if task
> setters
> would not set tasks with opposing traffic it would also help a lot -
> in my opinion the US competition scene will eventually make it
> mandatory
> to have Flarm or similar - in the very near future - the Flarm is not
> an
> expensive instrument - and remember that funerals and estate
> settlements
> are very, very expensive - hospitals as well -
> just my $0.02 worth
> locally I use the Zaon to see the jet and power traffic that can run
> you
> down from behind -

Chris O'Calahan was a friend and colleague and his tragic death has me
rethinking this whole subject. I've always been a big fan of ADS-B
but now I'm not so sure. I am absolutely sure if both gliders had
PowerFLARM, Chris would be alive.

ADS-B is at least a decade away (With inevitable delays - maybe two
decades) from completion. If you read the background tech
discussions, a fair sized constituency seems to be trying for force
ADS-B to simply replicate the current radar environment in a new
technology with few real advances for the average pilot beyond what we
have now with Mode-C. In any event, ADS-B will be primarily focused
on airplane operations and its usefulness to gliders will be
incidental.

PowerFLARM is exactly what we need and it will be available in months
not decades. The developers are tightly focused on glider operations
and will no doubt improve their product in the months and years to
come based on feedback from glider pilots - something I very much
doubt will be the case with ADS-B.

Darryl Ramm

August 9th 10, 08:50 PM

On Aug 9, 12:31*pm, "noel.wade" > wrote:
> Darryl & Brian -
>
> Thanks for the corrections on pricing. *Under $2k starts making it
> very attractive.
>
> Regarding the headless bit: *Its not just about power, its also
> installation location. *DG instrument panels/pods are great for
> ergonomics and bailout ability, but they don't have a lot of extra
> space for stuff like this. *I already have my ewMicroRecorder on top
> of the instrument pod and don't want to block my forward view. *A
> headless unit would allow me to install it under the seat-pan or
> behind my head, and a hookup to my PDA or a flight computer would
> still provide visual (and hopefully audible) cues when there was a
> collision risk.
>
> Regarding XCSoar: *I haven't used XCSoar in over a year and couldn't
> remember for sure to what degree it supported FLARM. *In LK8000 the
> FLARM support has been re-written and is much more fully-featured.
> Bottom-line: the more devices that support it, the better!
>
> --Noel

Noel

I had a DG-303 and I suspect the very best place for a Flarm like
device is on top of the glareshield, for both visibility and antenna
location and I'd be trying to move your flight recorder elsewhere if
you need the space. My old DG-303 panel was so tight (I like the full
size altimeters etc.) I had problem finding space for even small
things. I had my MRX PCAS mounted on top of the glareshield and it
worked great, and I made a smal sunshade that velcros on top of the
unit that helped with the display visibility. Although it depends on
your head height vs. the glareshield height I suspect a PowerFLARM by
itself will not intrude a lot into your visibility.

Darryl

Darryl Ramm

August 9th 10, 09:44 PM

On Aug 9, 9:23*am, brianDG303 > wrote:
> On Aug 9, 7:12*am, Renny > wrote:
[snip]
> Mike and Renny,
> a good discussion of the macro view of FLARM and ADS-B. Another view
> is more personal, for example in my situation- I fly a lot of ridge
> and mountain in a very narrow altitude band and a lot of clouds. There
> is not a lot of power traffic in those conditions. I have a
> transponder but I don't see the Transmit light going off very often
> and I suspect I am not getting very many radar paints down in the
> rocks and trees where I like to fly. My greatest risk is from the six
> other gliders I share the area with, which do not have transponders
> and will never get them at the current costs; in fairness my threat to
> them is even higher as I am a low hour pilot. FLARM would go a long
> way to reducing the risks and at a reasonable cost; PowerFlarm would
> be my choice as it would also provide protection from ADS-B and
> transponder equipped threats, but at twice the cost the installed base
> in my situation would be very much reduced and I stand a better chance
> of talking my potentially deadly friends into investing in FLARM. 2020
> is not soon enough. It is not soon enough for the pilots killed on a
> regular basis at contests, which we seem to simply accept as an
> unavoidable risk.
>
> With that in mind Mike's statement that FLARM isn't of use (for me)
> would not be correct. In 2004 my club lost two gliders and a pilot in
> a collision that would not have happens if they had had FLARM. How do
> you calculate that cost?
>
> Brian

Brian & folks

Sorry to hog the thread but I want to make sure that key technical
facts are nailed down.

Brian wrote...

> PowerFlarm would be my choice as it would also provide protection from ADS-B and
> transponder equipped threats, ...

PowerFLARM or any other 1090ES receiver in the USA will "see" other
ADS-B data-out equipped traffic if and only if one or more of the
following is true

1. ADS-B Direct. That other traffic is transmitting ADS-B data-out on
the same physical link layer (i.e. a Mode S transponder with 1090ES
data-out).

or 2. ADS-R (ADS-B Relay). That other traffic is transmitting on the
other physical link layer (i.e. a UAT transmitter or transceiver)
*and* your aircraft is correctly transmitting ADS-B data-out that
describes the aircraft location and ADS-B receiver configuration (aka
the "capability code" bits)
*and* both aircraft are within range of one or more ADS-B ground
stations
*and* the aircraft are within the ADS-R "service volume" (or "threat
cylinder" in my terminology) of what I beleive is +/- 3,500' and 15
nautical miles of each other

---

If you don't meet *all* the requirments in #2 above your ADS-B
receiver may still see other traffic, especially traffic near other
ADS-B data-out equipped aircraft, but there is no gaurentee that you
will see all traffic near you. The PowerFLARM is not an ADS-B
transmitter so you will need a Mode S transponder with 1090ES data-out
or a UAT transmitter/receiver to make the ADS-B traffic part of the
PowerFLARM work properly. My expectation is given that ADS-B is a damn
confusing mess that at least for the next several years pilots in the
USA who buy a PowerFLARM will likely mostly do so for the flarm-flarm
and PCAS capability, and if they also see 1090ES data-out aircraft
(esp. airliners and fast jets) that great, but I do worry that many
pilots won't understand they will not properly see say GA UAT equipped
traffic without an ADS-B transmitter.

---

The PowerFLARM has PCAS capability so is the threat aircraft
transponder is being interrogated the PowerFLARM should be able to
warn you of a threat and its relative altitude but it won't have
direction information. The nice thing about this is many of us have
positive experiences with Zaon MRX units where there seems to be good
interrogation even outside of standard SSR coverage (via TCAS and TCAD
interrogators etc). However if the concern is about ridges and other
fairly obscured sites then there just may not be enough interrogations
to make a transponder useful for a PCAS (PowerFLARM or Zaon MRX etc.)
unit to detect anything. Of course if the threat aircraft has a Mode S
1090ES data-out transponder then the PowerFLARM will directly the ADS-
B data from the transponder.

PowerFLARM will also have ADS-B TIS-B support but it is not initially
shipping with this enabled. TIS-B is the relay of other aircraft SSR
position data to ADS-B equipped aircraft so they can "see" transponder
only equipped traffic.

TIS-B (ADS-B Traffic Information System) requires that the other
traffic has a Mode C or S transponder
*and* is within coverage of a traditional SSR radar (or
multilateration system). i.e. think airspace where you have ATC radar
coverage today.
*and* your aircraft is correctly transmitting ADS-B data-out that
describes the aircraft location and ADS-B receiver configuration (aka
the "capability code" bits)
*and* your aircraft is within range of an ADS-B ground station
*and* the threat aircraft is within the TIS-B "service volume" (or
"threat cylinder" in my terminology) of your aircraft - I believe that
is is +/- 3,500' and 15 nautical miles.

---

Since Brian mentioned ridges as a scenario, a potential concern there
is that you may be frequently outside of ADS-B ground coverage and
therefore ADS-R services may be unreliable or not work at all. So even
if all the gliders are properly equipped a 1090ES ADS-B equipped
glider just won't "see" a UAT equipped glider an visa versa. Although
ADS-B ground station coverage compared to traditional SSR radar is
going to be impressive, including at many locations down to very low
altitudes, ADS-B as deployed in the USA just is not designed to deal
with scenarios like ridge soaring. To deal reliably with this glider-
on-glider ridge scenario all gliders in that area would need to adopt
a single physical ADS-B link layer (UAT or 1090ES) and/or adopt
PowerFLARM (for Flarm-Flarm). This is one reason I also claim that ADS-
B alone in gliders is not practical in the USA until somebody develops
a low cost dual-link layer receiver that can receive directly on both
1090ES and UAT. The ADS-R overage is a reason that busy ridge soaring
locations might want to be looking at the ADS-B GBT (ground station)
coverage maps and getting a feel how much this will be issue in their
area. Something probably a good idea for the SSA to be pushing to have
happen/coordinate.

Sorry to ramble on but this level of detail is really unfortunately
necessary in discussing these technologies.

Darryl

Mike Schumann

August 9th 10, 10:26 PM

On 8/9/2010 3:44 PM, Darryl Ramm wrote:
> On Aug 9, 9:23 am, > wrote:
>> On Aug 9, 7:12 am, > wrote:
> [snip]
>> Mike and Renny,
>> a good discussion of the macro view of FLARM and ADS-B. Another view
>> is more personal, for example in my situation- I fly a lot of ridge
>> and mountain in a very narrow altitude band and a lot of clouds. There
>> is not a lot of power traffic in those conditions. I have a
>> transponder but I don't see the Transmit light going off very often
>> and I suspect I am not getting very many radar paints down in the
>> rocks and trees where I like to fly. My greatest risk is from the six
>> other gliders I share the area with, which do not have transponders
>> and will never get them at the current costs; in fairness my threat to
>> them is even higher as I am a low hour pilot. FLARM would go a long
>> way to reducing the risks and at a reasonable cost; PowerFlarm would
>> be my choice as it would also provide protection from ADS-B and
>> transponder equipped threats, but at twice the cost the installed base
>> in my situation would be very much reduced and I stand a better chance
>> of talking my potentially deadly friends into investing in FLARM. 2020
>> is not soon enough. It is not soon enough for the pilots killed on a
>> regular basis at contests, which we seem to simply accept as an
>> unavoidable risk.
>>
>> With that in mind Mike's statement that FLARM isn't of use (for me)
>> would not be correct. In 2004 my club lost two gliders and a pilot in
>> a collision that would not have happens if they had had FLARM. How do
>> you calculate that cost?
>>
>> Brian
>
> Brian& folks
>
> Sorry to hog the thread but I want to make sure that key technical
> facts are nailed down.
>
> Brian wrote...
>
>> PowerFlarm would be my choice as it would also provide protection from ADS-B and
>> transponder equipped threats, ...
>
> PowerFLARM or any other 1090ES receiver in the USA will "see" other
> ADS-B data-out equipped traffic if and only if one or more of the
> following is true
>
> 1. ADS-B Direct. That other traffic is transmitting ADS-B data-out on
> the same physical link layer (i.e. a Mode S transponder with 1090ES
> data-out).
>
> or 2. ADS-R (ADS-B Relay). That other traffic is transmitting on the
> other physical link layer (i.e. a UAT transmitter or transceiver)
> *and* your aircraft is correctly transmitting ADS-B data-out that
> describes the aircraft location and ADS-B receiver configuration (aka
> the "capability code" bits)
> *and* both aircraft are within range of one or more ADS-B ground
> stations
> *and* the aircraft are within the ADS-R "service volume" (or "threat
> cylinder" in my terminology) of what I beleive is +/- 3,500' and 15
> nautical miles of each other
>
> ---
>
> If you don't meet *all* the requirments in #2 above your ADS-B
> receiver may still see other traffic, especially traffic near other
> ADS-B data-out equipped aircraft, but there is no gaurentee that you
> will see all traffic near you. The PowerFLARM is not an ADS-B
> transmitter so you will need a Mode S transponder with 1090ES data-out
> or a UAT transmitter/receiver to make the ADS-B traffic part of the
> PowerFLARM work properly. My expectation is given that ADS-B is a damn
> confusing mess that at least for the next several years pilots in the
> USA who buy a PowerFLARM will likely mostly do so for the flarm-flarm
> and PCAS capability, and if they also see 1090ES data-out aircraft
> (esp. airliners and fast jets) that great, but I do worry that many
> pilots won't understand they will not properly see say GA UAT equipped
> traffic without an ADS-B transmitter.
>
> ---
>
> The PowerFLARM has PCAS capability so is the threat aircraft
> transponder is being interrogated the PowerFLARM should be able to
> warn you of a threat and its relative altitude but it won't have
> direction information. The nice thing about this is many of us have
> positive experiences with Zaon MRX units where there seems to be good
> interrogation even outside of standard SSR coverage (via TCAS and TCAD
> interrogators etc). However if the concern is about ridges and other
> fairly obscured sites then there just may not be enough interrogations
> to make a transponder useful for a PCAS (PowerFLARM or Zaon MRX etc.)
> unit to detect anything. Of course if the threat aircraft has a Mode S
> 1090ES data-out transponder then the PowerFLARM will directly the ADS-
> B data from the transponder.
>
> PowerFLARM will also have ADS-B TIS-B support but it is not initially
> shipping with this enabled. TIS-B is the relay of other aircraft SSR
> position data to ADS-B equipped aircraft so they can "see" transponder
> only equipped traffic.
>
> TIS-B (ADS-B Traffic Information System) requires that the other
> traffic has a Mode C or S transponder
> *and* is within coverage of a traditional SSR radar (or
> multilateration system). i.e. think airspace where you have ATC radar
> coverage today.
> *and* your aircraft is correctly transmitting ADS-B data-out that
> describes the aircraft location and ADS-B receiver configuration (aka
> the "capability code" bits)
> *and* your aircraft is within range of an ADS-B ground station
> *and* the threat aircraft is within the TIS-B "service volume" (or
> "threat cylinder" in my terminology) of your aircraft - I believe that
> is is +/- 3,500' and 15 nautical miles.
>
> ---
>
> Since Brian mentioned ridges as a scenario, a potential concern there
> is that you may be frequently outside of ADS-B ground coverage and
> therefore ADS-R services may be unreliable or not work at all. So even
> if all the gliders are properly equipped a 1090ES ADS-B equipped
> glider just won't "see" a UAT equipped glider an visa versa. Although
> ADS-B ground station coverage compared to traditional SSR radar is
> going to be impressive, including at many locations down to very low
> altitudes, ADS-B as deployed in the USA just is not designed to deal
> with scenarios like ridge soaring. To deal reliably with this glider-
> on-glider ridge scenario all gliders in that area would need to adopt
> a single physical ADS-B link layer (UAT or 1090ES) and/or adopt
> PowerFLARM (for Flarm-Flarm). This is one reason I also claim that ADS-
> B alone in gliders is not practical in the USA until somebody develops
> a low cost dual-link layer receiver that can receive directly on both
> 1090ES and UAT. The ADS-R overage is a reason that busy ridge soaring
> locations might want to be looking at the ADS-B GBT (ground station)
> coverage maps and getting a feel how much this will be issue in their
> area. Something probably a good idea for the SSA to be pushing to have
> happen/coordinate.
>
> Sorry to ramble on but this level of detail is really unfortunately
> necessary in discussing these technologies.
>
> Darryl

I'm glad you posted this very informative item. As you point out, this
is an incredible mess. It didn't need to be that way, but that's what
you get with government engineering by political committee.

It's too bad that the FLARM guys didn't go after the US market when they
1st started their project in Europe years ago. It might have taken off
in the US GA market and created a defacto standard. No we have a huge
mess with no good answers in sight.

Certainly not a story that gets people excited about spending $$$$s to
upgrade their avionics.

--
Mike Schumann

John Cochrane

August 10th 10, 12:29 AM

I wrote a "contest corner" draft on Flarm in the US, motivated by my
experience with it at WGC.

http://faculty.chicagobooth.edu/john.cochrane/research/Papers/flarm.html

It's here, and it really helps with glider to glider midairs which are
the main problem at contests.

John Cochrane

Brad[_2_]

August 10th 10, 12:57 AM

On Aug 9, 4:29*pm, John Cochrane >
wrote:
> I wrote a "contest corner" draft on Flarm in the US, motivated by my
> experience with it at WGC.
>
> http://faculty.chicagobooth.edu/john.cochrane/research/Papers/flarm.html
>
> It's here, and it really helps with glider to glider midairs which are
> the main problem at contests.
>
> John Cochrane

Bravo John....................thanks for the link, and count me as on
of the "let's all get one" gang.

Brad
199AK

noel.wade

August 10th 10, 01:03 AM

Thanks, John. I was fortunate enough to do my primary single-engine
training in a nicely equipped set of Diamond DA-20 aircraft with glass
cockpits (though it was pretty damned expensive). They were equipped
with TIS displays and it was really great to get a sense of the other
air traffic around my training area (downtown Seattle has 4 major
Class D airports within a few miles of each other, all under Class B
airspace and with big jets taking off and landing at them all, as well
as a lot of GA and seaplane traffic). As long as people don't get
complacent, I firmly believe in the ability of a similar device to
increase situational awareness and safety!

Questions For The Competition Pilots out there:

Would you pay $$ to rent a powerFLARM unit for a Regional or National-
level contest?
What would you pay for 7 - 14 days of use of a powerFLARM?
Would you pay a higher contest entry fee if the contest provided FLARM
units for competitors?

--Noel

Brad[_2_]

August 10th 10, 01:18 AM

On Aug 9, 5:03*pm, "noel.wade" > wrote:
> Thanks, John. *I was fortunate enough to do my primary single-engine
> training in a nicely equipped set of Diamond DA-20 aircraft with glass
> cockpits (though it was pretty damned expensive). *They were equipped
> with TIS displays and it was really great to get a sense of the other
> air traffic around my training area (downtown Seattle has 4 major
> Class D airports within a few miles of each other, all under Class B
> airspace and with big jets taking off and landing at them all, as well
> as a lot of GA and seaplane traffic). *As long as people don't get
> complacent, I firmly believe in the ability of a similar device to
> increase situational awareness and safety!
>
> Questions For The Competition Pilots out there:
>
> Would you pay $$ to rent a powerFLARM unit for a Regional or National-
> level contest?
> What would you pay for 7 - 14 days of use of a powerFLARM?
> Would you pay a higher contest entry fee if the contest provided FLARM
> units for competitors?
>
> --Noel

Noel,

I've monitored Whidbey approach when flying up near Mt Vernon, I can't
tell you how many times I've heard the controller giving pilots heads
up for traffic and not one of the power guys ever saw each other. This
has happened many times.

I somewhat believe power pilots are complacent, believing that
technology will save them for a mid-air..................if you
recall, we almost got rammed by a twin while in the pattern at KAWO!

I don't like the idea of making FLARM available for rent. This is
something we should should equip our cockpits with and use ALL THE
TIME! I don't know what the learning curve is for Flarm, but if I ever
did fly a contest, I would want to know how Flarm works and not have
to "figure it out" in the cockpit during a contest.

Also, let's not stratify the use of Flarm for just contest pilots, the
airspace gets pretty busy just east KAWO too!

Is there a possibility of making Flarm simulator that we could
practice with on a PC? Perhaps some of the soaring flight simulators
have it, but I don't play with those.

On another note: If we are going to start tossing our ideas into the
hat...................please make sure LK8000 is compatible with
whatever Flarm unit is developed, pretty sure Paolo is all over that
anyways!

Brad

Darryl Ramm

August 10th 10, 01:28 AM

On Aug 9, 5:18*pm, Brad > wrote:
> On Aug 9, 5:03*pm, "noel.wade" > wrote:
>
>
>
> > Thanks, John. *I was fortunate enough to do my primary single-engine
> > training in a nicely equipped set of Diamond DA-20 aircraft with glass
> > cockpits (though it was pretty damned expensive). *They were equipped
> > with TIS displays and it was really great to get a sense of the other
> > air traffic around my training area (downtown Seattle has 4 major
> > Class D airports within a few miles of each other, all under Class B
> > airspace and with big jets taking off and landing at them all, as well
> > as a lot of GA and seaplane traffic). *As long as people don't get
> > complacent, I firmly believe in the ability of a similar device to
> > increase situational awareness and safety!
>
> > Questions For The Competition Pilots out there:
>
> > Would you pay $$ to rent a powerFLARM unit for a Regional or National-
> > level contest?
> > What would you pay for 7 - 14 days of use of a powerFLARM?
> > Would you pay a higher contest entry fee if the contest provided FLARM
> > units for competitors?
>
> > --Noel
>
> Noel,
>
> I've monitored Whidbey approach when flying up near Mt Vernon, I can't
> tell you how many times I've heard the controller giving pilots heads
> up for traffic and not one of the power guys ever saw each other. This
> has happened many times.
>
> I somewhat believe power pilots are complacent, believing that
> technology will save them for a mid-air..................if you
> recall, we almost got rammed by a twin while in the pattern at KAWO!
>
> I don't like the idea of making FLARM available for rent. This is
> something we should should equip our cockpits with and use ALL THE
> TIME! I don't know what the learning curve is for Flarm, but if I ever
> did fly a contest, I would want to know how Flarm works and not have
> to "figure it out" in the cockpit during a contest.
>
> Also, let's not stratify the use of Flarm for just contest pilots, the
> airspace gets pretty busy just east KAWO too!
>
> Is there a possibility of making Flarm simulator that we could
> practice with on a PC? Perhaps some of the soaring flight simulators
> have it, but I don't play with those.
>
> On another note: If we are going to start tossing our ideas into the
> hat...................please make sure LK8000 is compatible with
> whatever Flarm unit is developed, pretty sure Paolo is all over that
> anyways!
>
> Brad

Brad

Yes, but you got it kind of backwards - the LK8000 is developed to be
compatible with the publicly documented (and relatively simple) serial
FLARM protocol. Flarm established that protocol for a reason and
worked to get it widely adopted by software and flight computer
vendors. Which is why any ADS-B products trying to enter the glider
market without supporting this basic protocol is just unlikely to
happen.

I agree on your point, a contest day or practice day in crowded
airspace is just not the time to start dicking around learning how to
use or interpret any traffic warning system. And a simulator on a PC/
mac just would not convince me either (and I already play around with
SilentWings), pilots need to fly with the real thing. I think
investigating mandating Flarm type devices in USA contest makes sense
but I think proposing renting/loaning those systems would not be a
good idea.

Darryl

August 10th 10, 02:34 AM

On Aug 9, 12:46*pm, bildan > wrote:
> PowerFLARM is exactly what we need and it will be available in months
> not decades. *The developers are tightly focused on glider operations
> and will no doubt improve their product in the months and years to
> come based on feedback from glider pilots - something I very *much
> doubt will be the case with ADS-B.

Seems to me that another "niche" market for Flarm would be helicopters
flying around most big cities. There's usually several media outlets
with one, police and air ambulance. These aircraft have a tendency to
congregate around their own flavor of "hot spot", with similar
concerns as we have in gaggles, etc.

The more potential early adopters we can muster, the more likely this
could become a de-facto standard.

-Tom

Chris Nicholas[_2_]

August 10th 10, 04:32 AM

If you don't mind a bit of UK experience coming into this thread, I
would like to point out a fallacy in an earlier post. It is not true
that every glider has to have Flarm for it to be any good. If about
25% of gliders have it, then about 25% of potential collisions will be
alerted. You still have to look out anyway, both to decide what to do
about those potential collisions, and to look for other things whether
gliders or not that don't have Flarm.

For example, where I fly in eastern England, I believe less than 25%
of gliders have Flarm. I have the only one at my gliding club; none of
the other 12-15 gliders based there have it. I think only a few of the
gliders based at other nearby clubs are Flarm-equipped. Nevertheless,
last Sunday, I had two collision alerts. One was from my 11 o'clock.
Either the other glider had seen me first, and already taken action,
or it was not going to be close enough for an actual collision, just a
very near fly by; by the time I acquired him visually, he was already
passing me.

The other was with a glider in the same thermal as me, which I had
seen and whose presence was indicated by a green light on Flarm, until
he suddenly got behind me close enough for Flarm to alert imminent
collision (red lights and loud beeps). As it was then in my blind
spot, the only way I knew how close and how much threat he was came
from the Flarm unit, and I was able to speed up and get out of the way
before it turned into something nasty. (Last year, there was a real
collision between two UK gliders with almost exactly that geometry –
neither had Flarm working, and the one in front had no chance to see
it coming, in spite of efforts to see where the other had got to,
AIUI.)

Last time I checked with the main UK distributor, something like 25%
of UK gliders had Flarm and it was still growing.

From the correspondence I have seen, most UK pilots who have tried it
would not now be without it and really want the others to catch up.

It may be the case that a standalone Flarm unit like mine is a
temporary piece of technology which will be overtaken eventually by
ADS-B, or that plus Flarm, PowerFlarm, etc.. To my mind, it is worth
paying for even for a few years for partial assistance in collision
avoidance.

For the most common collisions in UK gliding, glider-glider, Flarm is
the only technology that can significantly help at the moment.

Transponders would do nothing for glider-glider collisions here. They
would do something for airliner (TCAS)-glider risks, but there have
been no such collisions, and the Airprox data suggest that they are
the least of our worries. Power general aviation-glider collisions
have taken place, but not nearly as many as glider-glider collisions.
Others have estimated transponder installation in general aviation is
still very much a minority in the UK. Even for those GA that do have
transponders, having a transponder in the glider as well provides
absolutely no “interoperability” (a CAA - civil aviation authority -
expression). Only if you receive a radar service, which is very rare
here, or if you have PCAS or similar, is a transponder going to be any
help in avoiding GA-glider incidents. I have a PCAS, because I fly in
an area with a lot of overflying GA, and I don't want to become a
statistic. I don't have a transponder, because the European
regulations, and the very strict adherence to them required by our
CAA, preclude me fitting one, as there is not a sufficiently detailed
approved modification required by European legislation.

So Flarm and PCAS is all I can do at the moment unless I invest in a
completely new instrument panel and layout, extra equipment, and the
cost and inconvenience of drawing up a very detailed modification
proposal that would be required, and paying for it to be officially
approved - a burden which is prohibitively expensive and time-
consuming, requiring skills I do not have.

Chris N

Eric Greenwell

August 10th 10, 05:21 AM

On 8/9/2010 11:22 AM, Mike Schumann wrote:
>
> Maybe the best solution is for the SSA to buy 50 basic FLARM boxes and
> rent them out to contests to use in the short term and wait for the
> FAA and the market to sort things out over the next 20 years.
I think this might be a good solution for contests for the next couple
of years. Flarm (the company) might be willing to sell or lease them
cheaply to SSA as a marketing ploy. Someone has to ask them about the
cost, then the contest committee needs to poll the pilots to determine
the level of support for the idea. This could be started now to have
ready in time for at least the National contests, and maybe several of
the big Regionals.

--
Eric Greenwell - Washington State, USA (netto to net to email me)

Steve Koerner

August 10th 10, 05:23 AM

Chris N:

I truly appreciate your comments and perspective on your own flarm
experience in the UK. However, I will note that your math is not
correct. If 25% of the gliders have flarm, then only one in 16
collisions can be averted, not 25% as you suggest. It is for
precisely that reason that it is necessary to have wide deployment of
the technology in order that it be significantly useful. I consider
that the logical mechanism to achieve wide deployment is to start by
mandating its use in sanctioned competition. I do hope that step is
taken for the 2011 US racing season.

Eric Greenwell

August 10th 10, 05:33 AM

On 8/9/2010 10:29 AM, Mike Schumann wrote:
> There are two parts to FLARM; an ADS-B type position reporting
> broadcast function, and a built in collision warning system.
>
> ADS-B transceivers typically do not include any collision warning
> logic. Instead they are more like modems. They transmit and receive
> position data in addition to receiving weather info, etc. This
> information is passed on to some form of graphics display device so
> that the locations of other aircraft can be shown on a moving map
> display relative to your own aircraft.
>
> The display device, in addition to showing the location of other
> aircraft, can also be programmed to provide collision warnings.
> Obviously, the typical flight trajectories of gliders are different
> than most power aircraft. I suspect that most glider specific moving
> map vendors will try to match FLARM's logic to minimize false alarms
> if they elect to provide a collision warning function in addition to
> just displaying the relative locations of other aircraft.
There seem to be some important differences between FLARM and ADS-B:

1. FLARM units broadcast the projected flight path of the glider they
are mounted in, which greatly reduces the computation load for
each FLARM. ADS-B doesn't do this, so each display device would
have compute the projected path for every glider in the gaggle.
That might be too much to do unless it was a dedicated device, and
it might not be done as accurately, because it would have fewer
GPS positions and speeds to work with.
2. FLARM units all use the same logic, enforced by mandatory updates,
to help ensure proper operation between all units. Would display
units with different techniques work as well?

--

Eric Greenwell - Washington State, USA (netto to net to email me)

- "Transponders in Sailplanes - Feb/2010" also ADS-B, PCAS, Flarm http://tinyurl.com/yb3xywl

- "A Guide to Self-launching Sailplane Operation Mar/2004" Much of what you need to know tinyurl.com/yfs7tnz

Eric Greenwell

August 10th 10, 05:38 AM

On 8/9/2010 6:34 PM, 5Z wrote:
> On Aug 9, 12:46 pm, > wrote:
>
>> PowerFLARM is exactly what we need and it will be available in months
>> not decades. The developers are tightly focused on glider operations
>> and will no doubt improve their product in the months and years to
>> come based on feedback from glider pilots - something I very much
>> doubt will be the case with ADS-B.
>>
> Seems to me that another "niche" market for Flarm would be helicopters
> flying around most big cities. There's usually several media outlets
> with one, police and air ambulance. These aircraft have a tendency to
> congregate around their own flavor of "hot spot", with similar
> concerns as we have in gaggles, etc.
>
> The more potential early adopters we can muster, the more likely this
> could become a de-facto standard.
>
This is already a European market for Flarm, so perhaps it would work
here, also.

There is another market that is developing, but I don't know if it would
be an asset to us: the huge trucks used in open pit mining. Knowing
exactly where they are helps the mine management optimize the use of the
trucks, and helps the trucks avoid obstacles. A truck that can carry 50
tons of dirt can do serious damage to anything it hits!

--
Eric Greenwell - Washington State, USA (netto to net to email me)

- "Transponders in Sailplanes - Feb/2010" also ADS-B, PCAS, Flarm http://tinyurl.com/yb3xywl

August 10th 10, 06:27 AM

When we can actually fly with an ADS-B system that is fully
functional, it'll be interesting to see how brilliantly it works in
the real world and how their algorithms are for dealing with formation
flying: IE glider on tow, or ten gliders in one thermal, without being
the boy who cried wolf.
Jim

Bob

August 10th 10, 06:54 AM

On Aug 9, 11:26*pm, Mike Schumann >
wrote:
> On 8/9/2010 3:44 PM, Darryl Ramm wrote:
>
>
>
>
>
> > On Aug 9, 9:23 am, > *wrote:
> >> On Aug 9, 7:12 am, > *wrote:
> > [snip]
> >> Mike and Renny,
> >> a good discussion of the macro view of FLARM and ADS-B. Another view
> >> is more personal, for example in my situation- I fly a lot of ridge
> >> and mountain in a very narrow altitude band and a lot of clouds. There
> >> is not a lot of power traffic in those conditions. I have a
> >> transponder but I don't see the Transmit light going off very often
> >> and I suspect I am not getting very many radar paints down in the
> >> rocks and trees where I like to fly. My greatest risk is from the six
> >> other gliders I share the area with, which do not have transponders
> >> and will never get them at the current costs; in fairness my threat to
> >> them is even higher as I am a low hour pilot. FLARM would go a long
> >> way to reducing the risks and at a reasonable cost; PowerFlarm would
> >> be my choice as it would also provide protection from ADS-B and
> >> transponder equipped threats, but at twice the cost the installed base
> >> in my situation would be very much reduced and I stand a better chance
> >> of talking my potentially deadly friends into investing in FLARM. 2020
> >> is not soon enough. It is not soon enough for the pilots killed on a
> >> regular basis at contests, which we seem to simply accept as an
> >> unavoidable risk.
>
> >> With that in mind Mike's statement that FLARM isn't of use (for me)
> >> would not be correct. In 2004 my club lost two gliders and a pilot in
> >> a collision that would not have happens if they had had FLARM. How do
> >> you calculate that cost?
>
> >> Brian
>
> > Brian& *folks
>
> > Sorry to hog the thread but I want to make sure that key technical
> > facts are nailed down.
>
> > Brian wrote...
>
> >> PowerFlarm would be my choice as it would also provide protection from ADS-B and
> >> transponder equipped threats, ...
>
> > PowerFLARM or any other 1090ES receiver in the USA will "see" other
> > ADS-B data-out equipped traffic if and only if one or more of the
> > following is true
>
> > 1. ADS-B Direct. That other traffic is transmitting ADS-B data-out on
> > the same physical link layer (i.e. a Mode S transponder with 1090ES
> > data-out).
>
> > or 2. ADS-R (ADS-B Relay). That other traffic is transmitting on the
> > other physical link layer (i.e. a UAT transmitter or transceiver)
> > * *and* your aircraft is correctly transmitting ADS-B data-out that
> > describes the aircraft location and ADS-B receiver configuration (aka
> > the "capability code" bits)
> > * *and* both aircraft are within range of one or more ADS-B ground
> > stations
> > * *and* the aircraft are within the ADS-R "service volume" (or "threat
> > cylinder" in my terminology) of what I beleive is +/- 3,500' and 15
> > nautical miles of each other
>
> > ---
>
> > If you don't meet *all* the requirments in #2 above your ADS-B
> > receiver may still see other traffic, especially traffic near other
> > ADS-B data-out equipped aircraft, but there is no gaurentee that you
> > will see all traffic near you. The PowerFLARM is not an ADS-B
> > transmitter so you will need a Mode S transponder with 1090ES data-out
> > or a UAT transmitter/receiver to make the ADS-B traffic part of the
> > PowerFLARM work properly. My expectation is given that ADS-B is a damn
> > confusing mess that at least for the next several years pilots in the
> > USA who buy a PowerFLARM will likely mostly do so for the flarm-flarm
> > and PCAS capability, and if they also see 1090ES data-out aircraft
> > (esp. airliners and fast jets) that great, but I do worry that many
> > pilots won't understand they will not properly see say GA UAT equipped
> > traffic without an ADS-B transmitter.
>
> > ---
>
> > The PowerFLARM has PCAS capability so is the threat aircraft
> > transponder is being interrogated the PowerFLARM should be able to
> > warn you of a threat and its relative altitude but it won't have
> > direction information. The nice thing about this is many of us have
> > positive experiences with Zaon MRX units where there seems to be good
> > interrogation even outside of standard SSR coverage (via TCAS and TCAD
> > interrogators etc). However if the concern is about ridges and other
> > fairly obscured sites then there just may not be enough interrogations
> > to make a transponder useful for a PCAS (PowerFLARM or Zaon MRX etc.)
> > unit to detect anything. Of course if the threat aircraft has a Mode S
> > 1090ES data-out transponder then the PowerFLARM will directly the ADS-
> > B data from the transponder.
>
> > PowerFLARM will also have ADS-B TIS-B support but it is not initially
> > shipping with this enabled. TIS-B is the relay of other aircraft SSR
> > position data to ADS-B equipped aircraft so they can "see" transponder
> > only equipped traffic.
>
> > TIS-B (ADS-B Traffic Information System) requires that the other
> > traffic has a Mode C or S transponder
> > * *and* is within coverage of a traditional SSR radar (or
> > multilateration system). i.e. think airspace where you have ATC radar
> > coverage today.
> > * *and* your aircraft is correctly transmitting ADS-B data-out that
> > describes the aircraft location and ADS-B receiver configuration (aka
> > the "capability code" bits)
> > * *and* your aircraft is within range of an ADS-B ground station
> > * *and* the threat aircraft is within the TIS-B "service volume" (or
> > "threat cylinder" in my terminology) of your aircraft - I believe that
> > is is +/- 3,500' and 15 nautical miles.
>
> > ---
>
> > Since Brian mentioned ridges as a scenario, a potential concern there
> > is that you may be frequently outside of ADS-B ground coverage and
> > therefore ADS-R services may be unreliable or not work at all. So even
> > if all the gliders are properly equipped a 1090ES ADS-B equipped
> > glider just won't "see" a UAT equipped glider an visa versa. Although
> > ADS-B ground station coverage compared to traditional SSR radar is
> > going to be impressive, including at many locations down to very low
> > altitudes, ADS-B as deployed in the USA just is not designed to deal
> > with scenarios like ridge soaring. To deal reliably with this glider-
> > on-glider ridge scenario all gliders in that area would need to adopt
> > a single physical ADS-B link layer (UAT or 1090ES) and/or adopt
> > PowerFLARM (for Flarm-Flarm). This is one reason I also claim that ADS-
> > B alone in gliders is not practical in the USA until somebody develops
> > a low cost dual-link layer receiver that can receive directly on both
> > 1090ES and UAT. The ADS-R overage is a reason that busy ridge soaring
> > locations might want to be looking at the ADS-B GBT (ground station)
> > coverage maps and getting a feel how much this will be issue in their
> > area. Something probably a good idea for the SSA to be pushing to have
> > happen/coordinate.
>
> > Sorry to ramble on but this level of detail is really unfortunately
> > necessary in discussing these technologies.
>
> > Darryl
>
> I'm glad you posted this very informative item. *As you point out, this
> is an incredible mess. *It didn't need to be that way, but that's what
> you get with government engineering by political committee.
>
> It's too bad that the FLARM guys didn't go after the US market when they
> 1st started their project in Europe years ago. *It might have taken off
> in the US GA market and created a defacto standard. *No we have a huge
> mess with no good answers in sight.
>
> Certainly not a story that gets people excited about spending $$$$s to
> upgrade their avionics.
>
> --
> Mike Schumann- Hide quoted text -
>
> - Show quoted text -

Mike

The "Flarm Guys" wanted to go to the US market when they first came
out but were advised by legal counsel in the US that they would have
"severe" liability problems. They are a small company, just 2 guys at
first. I am from the US and fly in a German club and when Flarm first
came out with the "No US citizens" codicil in the OpMan it was some
concern for the club. It hasn't been a problem so far and I would not
fly without a Flarm unit period! We have 100% compliance at our club.
I don't know what the numbers are for Germany, Italy, Austria,
Switzerland and France (the countries whose pilots I meet on a typical
Alps flight) but it appears quite high. Also the hang glider/
paraglider crowd is on board.
When I come back to the States eventually I hope Flarm/Pwr Flarm has
saturated the soaring market. It is the only way I'll be able to fly.

Bob

Bruce Hoult

August 10th 10, 08:42 AM

On Aug 10, 4:23*pm, Steve Koerner > wrote:
> Chris N:
>
> I truly appreciate your comments and perspective on your own flarm
> experience in the UK. *However, I will note that your math is not
> correct. * If 25% of the gliders have flarm, then only one in 16
> collisions can be averted, not 25% as you suggest.

That's not true because you having FLARM and other gliders having
FLARM are not independent random variables, unless you jump in a
different random glider every day.

If you choose to have FLARM and 25% of other gliders have FLARM then
you will be alerted to 25% of possible collisions, not 1/16.

If you choose not to have FLARM then you will be alerted to 0% of
possible collisions.

Chris Nicholas[_2_]

August 10th 10, 10:18 AM

I certainly hope that Bruce and I are correct, rather than Steve K. In
two seasons flying with Flarm, it went into full alarm mode three
times, two of them during the same flight last Sunday.

I would hate to think that I might have also had 15 times as many near
collisions with no Flarm indication in that period. It is bad enough
thinking that with average luck, I might have had as many as nine
others that I didn't see.

In fact, I suspect the numbers are so low that no trend can be
ascertained from this small sample.

What I can ascertain is that in every case, Flarm saw the threat and
raised the alert before my eyeball did. It also sees lots of green
contacts before I do. It's not that I don't look out, it is more that
I'm looking out with an imperfect tool for the job.

The same applies to powered aircraft which I detect with PCAS - there
are far more contacts than I see, but most are sufficiently far away
that they are not a threat anyway. I have only had one encounter that
led to real concern at the time.

Chris N

[email protected]

August 10th 10, 01:37 PM

Mike Schumann

August 10th 10, 02:21 PM

On 8/10/2010 12:27 AM, JS wrote:
> When we can actually fly with an ADS-B system that is fully
> functional, it'll be interesting to see how brilliantly it works in
> the real world and how their algorithms are for dealing with formation
> flying: IE glider on tow, or ten gliders in one thermal, without being
> the boy who cried wolf.
> Jim

Once again, ADS-B does not incorporate any collision avoidance logic.
It just identifies targets. The external display device that is
attached to the ADS-B receiver is responsible for any alerts.

Since this part of the system is not regulated by the FAA for VFR
applications, we will hopefully see some innovative solutions to this
challenge from people like See-You, Clear Nav, etc....

--
Mike Schumann

August 10th 10, 02:32 PM

On Aug 10, 6:21*am, Mike Schumann >
wrote:
> Since this part of the system is not regulated by the FAA for VFR
> applications, we will hopefully see some innovative solutions to this
> challenge from people like See-You, Clear Nav, etc....

Perhaps we can lobby AOPA to push a FLARM solution that integrates
with ADS-B as the solution for "the rest of us". Now would be a
perfect time considering the tragic loss of one of their staff.

One of the "problems" with ADS-B has been the cost and the lack of
clear benefits for the VFR, low & slow community, and this looks to be
the perfect storm to get something going.

-Tom

mattm[_2_]

August 10th 10, 03:45 PM

On Aug 10, 12:21*am, Eric Greenwell > wrote:
> On 8/9/2010 11:22 AM, Mike Schumann wrote:
>
> > Maybe the best solution is for the SSA to buy 50 basic FLARM boxes and
> > rent them out to contests to use in the short term and wait for the
> > FAA and the market to sort things out over the next 20 years.
>
> I think this might be a good solution for contests for the next couple
> of years. Flarm (the company) might be willing to sell or lease them
> cheaply to SSA as a marketing ploy. Someone has to ask them about the
> cost, then the contest committee needs to poll the pilots to determine
> the level of support for the idea. This could be started now to have
> ready in time for at least the National contests, and maybe several of
> the big Regionals.
>
> --
> Eric Greenwell - Washington State, USA (netto to net to email me)

There is something to be said for this. The peak number of planes
flying contests at one time this year (or at least registered) was on
May 15th,
when there were 37 at R9 South and 47 at R2 Mifflin. If this unit is
like
other Flarms it also works as an IGC logger (I don't see it on the
web
description however). If each unit rented out 20 times over a 5 year
span at $100 plus shipping (if it survived that long!) it would pay
for itself.

On the other hand we didn't do anything like that when we introduced
igc recorders to contest flying, even though there was a steep price
to pay for them, and even though there was a big improvement in
task calling and flight scoring available from using them. Those 50
units would represent an $80K outlay, plus the administrative cost
of keeping track of them, getting them fixed when they break, etc.

-- Matt

August 10th 10, 03:51 PM

On Aug 10, 8:37*am, wrote:
> On Aug 10, 12:21*am, Eric Greenwell > wrote:
>
>
>
> > On 8/9/2010 11:22 AM, Mike Schumann wrote:
>
> > > Maybe the best solution is for the SSA to buy 50 basic FLARM boxes and
> > > rent them out to contests to use in the short term and wait for the
> > > FAA and the market to sort things out over the next 20 years.
>
> > I think this might be a good solution for contests for the next couple
> > of years. Flarm (the company) might be willing to sell or lease them
> > cheaply to SSA as a marketing ploy. Someone has to ask them about the
> > cost, then the contest committee needs to poll the pilots to determine
> > the level of support for the idea. This could be started now to have
> > ready in time for at least the National contests, and maybe several of
> > the big Regionals.
>
> > --
> > Eric Greenwell - Washington State, USA (netto to net to email me)
>
> This topic is on the list for the 2010 pilot poll.
> UH
> RC Chair

I think we can safely say that a collision avoidance device that takes
up no space, uses no power, gives only good information and costs no
money would be embraced by (almost) all.

Speaking for myself, I have an issue with family. They trust me to
stay out of rocks and trees, and make sure the glider is put together
right. They *worry* about midairs. I do to. This is the hazard that
by definition catches you unaware. So I am motivated.

Several times I have reviewed flight logs from contest legs where I
flew "all alone" to discover, after the fact, that there were several
other ships within visual range that I never saw. I've used that
discovery to work hard on my scan discipline and I believe I have
improved, but I *know* I'm not getting all the traffic. So I know
that eyeballs aren't enough.

What's needed is more credible evaluation & tire kicking &
understanding of where the faults are, and how it works (or not) with
GA. Thank you to those who have posted their experiences here -- this
is very helpful. The benefit/cost ratio appears to be pleasingly
high.

-Evan Ludeman / T8

August 10th 10, 03:58 PM

On Aug 10, 8:37*am, wrote:
> On Aug 10, 12:21*am, Eric Greenwell > wrote:
>
>
>
> > On 8/9/2010 11:22 AM, Mike Schumann wrote:
>
> > > Maybe the best solution is for the SSA to buy 50 basic FLARM boxes and
> > > rent them out to contests to use in the short term and wait for the
> > > FAA and the market to sort things out over the next 20 years.
>
> > I think this might be a good solution for contests for the next couple
> > of years. Flarm (the company) might be willing to sell or lease them
> > cheaply to SSA as a marketing ploy. Someone has to ask them about the
> > cost, then the contest committee needs to poll the pilots to determine
> > the level of support for the idea. This could be started now to have
> > ready in time for at least the National contests, and maybe several of
> > the big Regionals.
>
> > --
> > Eric Greenwell - Washington State, USA (netto to net to email me)
>
> This topic is on the list for the 2010 pilot poll.
> UH
> RC Chair

I think we can safely say that a collision avoidance device that takes
up no space, uses no power, gives only good information and costs no
money would be embraced by (almost) all. So the question of whether
to adopt any specific technology is largely question of benefits vs.
cost.

Speaking for myself, I have an issue with family. They trust me to
stay out of rocks and trees, and make sure the glider is put together
right. They *worry* about midairs. I do, too. This is the hazard
that
by definition catches you unaware. So I am motivated.

Several times I have reviewed flight logs from contest legs where I
flew "all alone" to discover, after the fact, that there were several
other ships within visual range that I never saw. I've used that
discovery to work hard on my scan discipline and I believe I have
improved, but I *know* I'm not getting all the traffic. So I know
that eyeballs aren't enough.

What's needed is more credible evaluation & tire kicking &
understanding of where the faults are, and how it works (or not) with
GA. Thank you to those who have posted their experiences here -- this
is very helpful. The benefit/cost ratio appears to be pleasingly
high.

-Evan Ludeman / T8

Andy[_10_]

August 10th 10, 04:08 PM

On Aug 10, 5:37*am, wrote:
> On Aug 10, 12:21*am, Eric Greenwell > wrote:
>
>
>
>
>
> > On 8/9/2010 11:22 AM, Mike Schumann wrote:
>
> > > Maybe the best solution is for the SSA to buy 50 basic FLARM boxes and
> > > rent them out to contests to use in the short term and wait for the
> > > FAA and the market to sort things out over the next 20 years.
>
> > I think this might be a good solution for contests for the next couple
> > of years. Flarm (the company) might be willing to sell or lease them
> > cheaply to SSA as a marketing ploy. Someone has to ask them about the
> > cost, then the contest committee needs to poll the pilots to determine
> > the level of support for the idea. This could be started now to have
> > ready in time for at least the National contests, and maybe several of
> > the big Regionals.
>
> > --
> > Eric Greenwell - Washington State, USA (netto to net to email me)
>
> This topic is on the list for the 2010 pilot poll.
> UH
> RC Chair

I did a back of the envelope on the rental idea a couple of weeks ago.
Depending on how many non-overlapping contests you can serve, the
price you buy the PowerFlarms at and whether you sell/replace the
units that have been in service a few years, it seems you could rent
them out at $40-70 per contest at breakeven. This year at least there
weren't many schedule conflicts on the big contests, but some are back-
to-back, so you'd need an efficient system for management and
logistics. I doubt the Flarm guys would want to donate or lease 50
units, but they might be willing to give favorable pricing to help get
the US market going and really show the value in the toughest
environment - contests.

I'm in favor of doing something. I believe the statistics show that
the biggest midair threat is glider-glider at contests and covering
contests would seed the market among many of the pilot who fly the
most.

9B

Frank Whiteley

August 10th 10, 04:15 PM

On Aug 10, 7:32*am, 5Z > wrote:
> On Aug 10, 6:21*am, Mike Schumann >
> wrote:
>
> > Since this part of the system is not regulated by the FAA for VFR
> > applications, we will hopefully see some innovative solutions to this
> > challenge from people like See-You, Clear Nav, etc....
>
> Perhaps we can lobby AOPA to push a FLARM solution that integrates
> with ADS-B as the solution for "the rest of us". *Now would be a
> perfect time considering the tragic loss of one of their staff.
>
> One of the "problems" with ADS-B has been the cost and the lack of
> clear benefits for the VFR, low & slow community, and this looks to be
> the perfect storm to get something going.
>
> -Tom

If you want to engage AOPA in this, visit the AOPA web site and see
the pilot meetings under Engage in AOPA. AOPA members in various
areas should have had an e-mail notification of these meetings and can
submit questions in advance. Of course, the meeting agendas are going
to be pretty tightly controlled as they are short and themed, but
Craig Fuller will be there with a congressman or senator. The
unfortunate irony is that Chris O'Callaghan was one of the pilots
involved in the current east coast Mitre ADS-B tests.

Frank Whiteley

Surfer![_2_]

August 10th 10, 04:59 PM

"Darryl Ramm" > wrote in message
...
<snip>
>
> I had a DG-303 and I suspect the very best place for a Flarm like
> device is on top of the glareshield, for both visibility and antenna
> location and I'd be trying to move your flight recorder elsewhere if
> you need the space.
<snip>

Writing from the UK.

I have a Swiss Flarm, the original type, which mounts on top of my panel.
However I've realised it's not the best choice for my particular glider as
if I ever have to jump, the cover over the panel goes with the canopy. It
would have been much easier to do a safe installation (e.g. one with greatly
reduced risk of stopping the canopy ejecting) with a Red Box Flarm, which is
headless and can be fitted somewhere behind the panel or (I suspect) even
secured to the inside of the fus with Velcro.

However the Flarm itself works well. Mine is an IGC logger as well (and the
Red Box is available in an IGC version). I haven't flown a huge amount
since I got it, but it seems to have worked well on it's few XC outings.
The one thing that is always in my mind when I get an alert and I *think* I
see the threat is if it really is the thread. I treat the alarm as a 'lot
out even more' warning rather than a 'look at the display' warning.

Brad[_2_]

August 10th 10, 05:05 PM

On Aug 10, 8:08*am, Andy > wrote:
> On Aug 10, 5:37*am, wrote:
>
>
>
>
>
> > On Aug 10, 12:21*am, Eric Greenwell > wrote:
>
> > > On 8/9/2010 11:22 AM, Mike Schumann wrote:
>
> > > > Maybe the best solution is for the SSA to buy 50 basic FLARM boxes and
> > > > rent them out to contests to use in the short term and wait for the
> > > > FAA and the market to sort things out over the next 20 years.
>
> > > I think this might be a good solution for contests for the next couple
> > > of years. Flarm (the company) might be willing to sell or lease them
> > > cheaply to SSA as a marketing ploy. Someone has to ask them about the
> > > cost, then the contest committee needs to poll the pilots to determine
> > > the level of support for the idea. This could be started now to have
> > > ready in time for at least the National contests, and maybe several of
> > > the big Regionals.
>
> > > --
> > > Eric Greenwell - Washington State, USA (netto to net to email me)
>
> > This topic is on the list for the 2010 pilot poll.
> > UH
> > RC Chair
>
> I did a back of the envelope on the rental idea a couple of weeks ago.
> Depending on how many non-overlapping contests you can serve, the
> price you buy the PowerFlarms at and whether you sell/replace the
> units that have been in service a few years, it seems you could rent
> them out at $40-70 per contest at breakeven. This year at least there
> weren't many schedule conflicts on the big contests, but some are back-
> to-back, so you'd need an efficient system for management and
> logistics. I doubt the Flarm guys would want to donate or lease 50
> units, but they might be willing to give favorable pricing to help get
> the US market going and really show the value in the toughest
> environment - contests.
>
> I'm in favor of doing something. I believe the statistics show that
> the biggest midair threat is glider-glider at contests and covering
> contests would seed the market among many of the pilot who fly the
> most.
>
> 9B

I don't want to see the "first" batch of Flarms going to just contest
pilots. Contest pilots are not the only ones to run in to each other.
If you want to see a lawsuit, go ahead and prioritize who get's them.
There are way more "just for fun" flights in the US than contest
flights.................I value my life and the guys I fly with as
much as the contest guys value their lives and the guys they fly with.

As far as flying "the most", I'd like to see the statistics showing
contest hours and non-contest hours flown.

Regards,
Brad

Steve Koerner

August 10th 10, 05:06 PM

The flaw to the rental idea is that it demotivates purchase of the
units and therefor diminishes the oppourtunity for improved safety on
non-contest flights. It has been reported here that in some
countries Flarm has reached near universal adoption and that safety
has been greatly enhanced as a result. I would not want to see us
adopt a scheme that makes achieving that same result unlikely or
significantly defered.

Chris Nicholas[_2_]

August 10th 10, 05:16 PM

Another observation from across the pond, if I may.

I have the most basic Flarm, which is a very small compact unit, but
requires an external battery source. I run it from a battery I carry
on with me, stuffed behind the glider seat, and the Flarm sits on top
of the instrument panel coaming with “hook and loop” tape. I have mine
retrofitted with the IGC Logger capability. You can buy new ones with
this capability already installed, now.

The Power Flarm, as I understand it, is a much bulkier item. I don't
know how that would work out for people to rent it and use temporarily
during competitions. You would have to sort out the power
requirements. Not everybody can stuff an extra battery into the glider
in the way that I can in mine.

If you want to see a picture of my glider with its Flarm, PCAS, and
other bolt on goodies on the instrument panel, see :
http://picasaweb.google.com/cnich15000/DropBox?authkey=Gv1sRgCPDsytW03-n8WA#5502778413677251106
..

[I hope this works – I have not tried it before!]

And one other observation. "The best is the enemy of the good". I
decided to get something that would help with avoiding some collisions
now, rather than wait for the ultimate solution where everyone has
interoperability with everybody else all in one compact box that is
affordable, can be fitted under the relevant regulations, gives a
graphic display, has no disadvantages, and and and. I might not live
that long. I certainly don't think I will be gliding that long.

Chris N

Mike Schumann

August 10th 10, 05:26 PM

On 8/10/2010 11:06 AM, Steve Koerner wrote:
> The flaw to the rental idea is that it demotivates purchase of the
> units and therefor diminishes the oppourtunity for improved safety on
> non-contest flights. It has been reported here that in some
> countries Flarm has reached near universal adoption and that safety
> has been greatly enhanced as a result. I would not want to see us
> adopt a scheme that makes achieving that same result unlikely or
> significantly defered.
You are never going to get the average Cessna pilot to buy a FLARM unit
in the US, when he knows he is going to eventually have to buy an ADS-B
transmitter. FLARM is useless unless you have a significant number of
other aircraft equipped. Renting units in contests is a quick and
viable way to solve this immediate problem. If you want to solve the
problem for the recreational flyer, ADS-B is the solution, particularly
when you consider that most weekend flying is probably happening near
major metropolitan areas which will have ground station coverage, and
where much of the power GA traffic is already transponder equipped.

--
Mike Schumann

Brad[_2_]

August 10th 10, 05:35 PM

> problem for the recreational flyer, ADS-B is the solution, particularly
> when you consider that most weekend flying is probably happening near
> major metropolitan areas which will have ground station coverage, and
> where much of the power GA traffic is already transponder equipped.

Not true at all. Where we fly our XC routes is back in the mountains.
As far as I know there isn't much GA traffic or station coverage back
there. But, there can be several gliders and I would like to have
something besides my visual scan to alert me to their presence. It
seems Flarm in "our" cockpits would do that?

We are also not "weekend only" flyers, we fly several days out of the
week during the summer and for that matter during the flying season.

Now, on the other hand.............I would imagine due to work, family
and financial obligations the flights made by contest pilots happen 2
or maybe 3 times a year, or at least as many contests their other
obligations allow them to fly.

So, perhaps the contest pilot who "only" gets to fly a few contest
pilots a year perhaps isn't so up on his skills as a pilot who flies
year round?

Not to get in to a ****ing contest here, but anything that excludes
one group of pilots over another is not a viable solution, in my
opinion.

Flarm should be made available to ALL glider pilots. Didn't I just
read "the best is the enemy of the good"?

Brad

bildan

August 10th 10, 05:47 PM

On Aug 10, 10:26*am, Mike Schumann >
wrote:
> On 8/10/2010 11:06 AM, Steve Koerner wrote:> The flaw to the rental idea is that it demotivates purchase of the
> > units and therefor diminishes the oppourtunity for improved safety on
> > non-contest flights. * It has been reported here that in some
> > countries Flarm has reached near universal adoption and that safety
> > has been greatly enhanced as a result. *I would not want to see us
> > adopt a scheme that makes achieving that same result unlikely or
> > significantly defered.
>
> You are never going to get the average Cessna pilot to buy a FLARM unit
> in the US, when he knows he is going to eventually have to buy an ADS-B
> transmitter. *FLARM is useless unless you have a significant number of
> other aircraft equipped. *Renting units in contests is a quick and
> viable way to solve this immediate problem. *If you want to solve the
> problem for the recreational flyer, ADS-B is the solution, particularly
> when you consider that most weekend flying is probably happening near
> major metropolitan areas which will have ground station coverage, and
> where much of the power GA traffic is already transponder equipped.
>
> --
> Mike Schumann

Unless, I'm misreading the specifications, there's no need for Cessna
drivers to buy PowerFLARM units. PowerFLARM can detect Mode C and ADS-
B if the glider and Cessna are in range of an interrogating radar in
the same manner as current "transponder detectors".

ADS-B, unless the camel designing committees in the FAA screw it up,
will be a nice solution but it's a LONG way off. Further off than the
replacement cycle life of most glider avionics. Buy PowerFLARM now
and by the time ADS-B is truly useful, the PF unit will need
replacement anyway.

Finally, It's entirely possible by the time ADS-B is here, the
PowerFLARM folks will have full ADS-B functionality built into their
units.

Andy[_1_]

August 10th 10, 06:21 PM

On Aug 10, 12:42*am, Bruce Hoult > wrote:

> If you choose to have FLARM and 25% of other gliders have FLARM then
> you will be alerted to 25% of possible collisions, not 1/16.
>
> If you choose not to have FLARM then you will be alerted to 0% of
> possible collisions.

I'm not going to argue with either person's math but I think different
assumptions are being made. In one case the total number of avoided
collisions is being considered. In the other case the avoided
collisions are only those involving one of the FLARM equipped gliders.

Andy

Mike Schumann

August 10th 10, 06:45 PM

On 8/10/2010 11:35 AM, Brad wrote:
>
>> problem for the recreational flyer, ADS-B is the solution, particularly
>> when you consider that most weekend flying is probably happening near
>> major metropolitan areas which will have ground station coverage, and
>> where much of the power GA traffic is already transponder equipped.
>
> Not true at all. Where we fly our XC routes is back in the mountains.
> As far as I know there isn't much GA traffic or station coverage back
> there. But, there can be several gliders and I would like to have
> something besides my visual scan to alert me to their presence. It
> seems Flarm in "our" cockpits would do that?
>
> We are also not "weekend only" flyers, we fly several days out of the
> week during the summer and for that matter during the flying season.
>
> Now, on the other hand.............I would imagine due to work, family
> and financial obligations the flights made by contest pilots happen 2
> or maybe 3 times a year, or at least as many contests their other
> obligations allow them to fly.
>
> So, perhaps the contest pilot who "only" gets to fly a few contest
> pilots a year perhaps isn't so up on his skills as a pilot who flies
> year round?
>
> Not to get in to a ****ing contest here, but anything that excludes
> one group of pilots over another is not a viable solution, in my
> opinion.
>
> Flarm should be made available to ALL glider pilots. Didn't I just
> read "the best is the enemy of the good"?
>
> Brad
>
FLARM does you no good, if the aircraft that you are about to hit
doesn't have FLARM installed. No one is suggesting that you not be able
to buy FLARM. It's just not going to do you any good if the other
aircraft flying in your area are also not FLARM equipped.

If you are flying in a remote area, with a couple of other glider pilots
and you all buy FLARM, you have protection from each other, but not the
stray GA pilot who may wander thru the area. That may be good enough
for you and if you have a small enough group, you may be able to
convince everyone to buy a unit.

If you are flying near a major metro area, there is absolutely no way
you are going to get everyone in the area to invest in FLARM. In that
environment, you will also probably be flying within range of an ADS-B
ground station, so investing in ADS-B is definitely the way to go. Not
only will you see other ADS-B equipped aircraft, but you also will see
all other Mode C/S transponder equipped aircraft that show up on ATC radar.

--
Mike Schumann

Mike Schumann

August 10th 10, 06:51 PM

On 8/10/2010 11:47 AM, bildan wrote:
> On Aug 10, 10:26 am, Mike >
> wrote:
>> On 8/10/2010 11:06 AM, Steve Koerner wrote:> The flaw to the rental idea is that it demotivates purchase of the
>>> units and therefor diminishes the oppourtunity for improved safety on
>>> non-contest flights. It has been reported here that in some
>>> countries Flarm has reached near universal adoption and that safety
>>> has been greatly enhanced as a result. I would not want to see us
>>> adopt a scheme that makes achieving that same result unlikely or
>>> significantly defered.
>>
>> You are never going to get the average Cessna pilot to buy a FLARM unit
>> in the US, when he knows he is going to eventually have to buy an ADS-B
>> transmitter. FLARM is useless unless you have a significant number of
>> other aircraft equipped. Renting units in contests is a quick and
>> viable way to solve this immediate problem. If you want to solve the
>> problem for the recreational flyer, ADS-B is the solution, particularly
>> when you consider that most weekend flying is probably happening near
>> major metropolitan areas which will have ground station coverage, and
>> where much of the power GA traffic is already transponder equipped.
>>
>> --
>> Mike Schumann
>
> Unless, I'm misreading the specifications, there's no need for Cessna
> drivers to buy PowerFLARM units. PowerFLARM can detect Mode C and ADS-
> B if the glider and Cessna are in range of an interrogating radar in
> the same manner as current "transponder detectors".
>
> ADS-B, unless the camel designing committees in the FAA screw it up,
> will be a nice solution but it's a LONG way off. Further off than the
> replacement cycle life of most glider avionics. Buy PowerFLARM now
> and by the time ADS-B is truly useful, the PF unit will need
> replacement anyway.
>
> Finally, It's entirely possible by the time ADS-B is here, the
> PowerFLARM folks will have full ADS-B functionality built into their
> units.

If you are flying in a remote area, outside of radar coverage, there is
a very good chance that a transponder equipped aircraft will not be
interrogated on a regular basis, and, as a result, will NOT show up on
PowerFlarm or other PCAS type units.

--
Mike Schumann

noel.wade

August 10th 10, 06:56 PM

A few points:

1) I still think the rental idea has merit. If people are unconvinced
about buying one, letting them use it for 1 week in a crowded
environment (i.e. a contest or busy flying-site) for only $100 - $150
would be a good way to introduce them to the unit and convince them
that its worthy of purchasing. The hope is that they would go home
after the contest is over and buy one. A "try before you buy" type
program, if you will. If I had the capital to purchase 30 of these, I
would start this business tomorrow (sadly I only have the $$ to buy
about 10 - 15, without getting external investors involved).

2) The powerFLARM unit uses AA batteries, no need for external
wiring.

3) The powerFLARM only has 1 rotary knob for control, and a pretty
self-explanatory display system. Not sure how much fiddling would be
required by a renter to get comfortable with it. Mounting might be a
hassle, but velco on the glareshield is the easy solution (like people
do with Zaon systems now). If rented at a contest, the idea would be
to get used to it on the Practice Day.

4) The powerFLARM is already ADS-B compliant. Yes, it does not have
a transmitter; but I don't think you're going to see that. ADS-B
transmit requirements are far more stringent than FLARM. It would be
a bigger power-drain and more antennas would be needed. I think
there's a good argument for separating your ADS-B "In" (i.e. collision
alert & display systems) from your ADS-B "Out" (i.e. transponder-like
functions) equipment, due to the big differences in antennas and power
requirements that each component needs.

5) Brad, its not about STOPPING non-contest pilots from adopting the
FLARM. But contest pilots tend to be early-adopters of new
technology, and tend to be the people who are more willing to spend $$
to upgrade their glider. The idea is to use this crowd to establish a
"beachhead" in the USA. Get a certain minimum % of the pilots using
FLARM and then it'll spread from there. Pilots already spend several
hundred $$ for contest entries and hotels/meals while at a contest -
so many of them wouldn't balk too much about an additional $100 for
the FLARM rental. Asking casual pilots to fork out an additional $50
- $100 for a weekend of flying with one is a much different issue!
Contests are just the starting point, to try to springboard the system
into widespread acceptance.

6) If the powerFLARM can replace a Volkslogger or ewMicroRecorder or
similar device, that would make it even more attractive, for sure!
Its got the GPS capability, so the security features and data output
(to SD card or something similar) is the only missing piece.

--Noel
(who also still likes the idea of a headless unit for purchase, to aid
in mounting and integration with other displays/flight-computers).

noel.wade

August 10th 10, 07:01 PM

On Aug 10, 10:51*am, Mike Schumann >
wrote:

> If you are flying in a remote area, outside of radar coverage, there is
> a very good chance that a transponder equipped aircraft will not be
> interrogated on a regular basis, and, as a result, will NOT show up on
> PowerFlarm or other PCAS type units.

Mike - that's why powerFLARM includes FLARM and ADS-B detection, in
addition to Mode C/S Transponder interrogation replies. So powerFLARM
gives you the ability to detect any aircraft equipped with any of
these systems.

And note that until the entire GA fleet is equipped with ADS-B (in
2020 or beyond), the ONLY system that is actively transmitting all the
time is the FLARM protocol! Its the best guarantee among aircraft in
close proximity, no matter where they're flying or what radar coverage
they do/don't have.

ADS-B holds the same "always on" promise of FLARM, but the difference
is that FLARM is a developed product whereas ADS-B is still 5 - 15
years away.

--Noel

noel.wade

August 10th 10, 07:04 PM

Sorry to spam the thread. Just noticed on the Craggy website that the
powerFLARM _does_ include IGC flight logging. Cool!

http://www.craggyaero.com/powerflarm.htm

--Noel

August 10th 10, 07:19 PM

On Aug 10, 2:04*pm, "noel.wade" > wrote:
> Sorry to spam the thread. *Just noticed on the Craggy website that the
> powerFLARM _does_ include IGC flight logging. *Cool!
>
> http://www.craggyaero.com/powerflarm.htm
>
> --Noel

Details, please, if anyone has them. It seems unlikely that it would
include an aneroid altimeter or engine run monitor... perhaps it is
good enough to be a backup logger for comp use? How does one extract
the logs?

-T8

Tuno

August 10th 10, 07:21 PM

Andy --

I'm unable to load the FLARM web page to investigate, but I'm curious
about "intelligent alerting based on glider flight characteristics."
Can you (or anyone) confirm that PowerFLARMs would have detected (and
warned) last week's head-on in Uvalde?

What glider flight characteristics in particular play into FLARM's
algorithms?

~ted/2NO

sisu1a

August 10th 10, 07:25 PM

>How does one extract
> the logs?

http://af-design.com/blog/wp-content/uploads/2008/09/hammer_and_screwdriver-300x225.jpg
....or I hear Bob K. has a sawzall in case that doesn't work ;)

Seriously though, great discussion, carry on.

sisu1a

August 10th 10, 07:34 PM

> >How does one extract
> > the logs?

....ultimate log extractor: http://www.techfresh.net/wp-content/uploads/2008/05/logging-spider.jpg

FWIW I think the contest rental idea sounds like a great plan, and I'm
sure the FLARM guys would come down in price for bulk reasons as well
as the promotional factor.

Beyond discounted units for contest rentals, I think it would be in
FLARM's interests as well to sell the first hundred or two units in
USA for a significant discount to get the ball rolling towards
critical mass.

-Paul

Chris Nicholas[_2_]

August 10th 10, 07:46 PM

My understanding is that Flarm uses a pressure capsule anyway for
height information, not GPS height. The IGC version certainly uses the
pressure capsule for height verification, and it comes with a
calibration chart.

If you opt for the engine sensing function on the logger, I presume it
uses a microphone, though I don't know for sure.

If you can't get into the Flarm website, you could try accessing the
UK agents website at:

http://www.lxavionics.co.uk/traffic-monitor.htm

for PowerFlarm, and there is a link on that page to the other Flarm
options.

I should mention that I have no commercial interest in this at all,
except as a satisfied customer.

Chris N

Andy[_1_]

August 10th 10, 07:53 PM

On Aug 10, 11:19*am, T8 > wrote:
> Details, please, if anyone has them. *It seems unlikely that it would
> include an aneroid altimeter or engine run monitor... perhaps it is
> good enough to be a backup logger for comp use? *How does one extract
> the logs?

The specification indicates that it includes a baro sensor and has a
micro SD card slot.

I saw nothing that indicates it is intended to be an IGC approved
recorder but, as far as I know, the product is still in development
and the web site may not be current. The specs are certainly quite
sparse.

Andy

Andy[_1_]

August 10th 10, 07:58 PM

On Aug 10, 11:53*am, Andy > wrote:
> The specs are certainly quite
> sparse.

But do include "integrated microphone" so ENL looks possible.

Mike Schumann

August 10th 10, 08:16 PM

On 8/10/2010 1:01 PM, noel.wade wrote:
> On Aug 10, 10:51 am, Mike >
> wrote:
>
>> If you are flying in a remote area, outside of radar coverage, there is
>> a very good chance that a transponder equipped aircraft will not be
>> interrogated on a regular basis, and, as a result, will NOT show up on
>> PowerFlarm or other PCAS type units.
>
> Mike - that's why powerFLARM includes FLARM and ADS-B detection, in
> addition to Mode C/S Transponder interrogation replies. So powerFLARM
> gives you the ability to detect any aircraft equipped with any of
> these systems.
>
> And note that until the entire GA fleet is equipped with ADS-B (in
> 2020 or beyond), the ONLY system that is actively transmitting all the
> time is the FLARM protocol! Its the best guarantee among aircraft in
> close proximity, no matter where they're flying or what radar coverage
> they do/don't have.
>
> ADS-B holds the same "always on" promise of FLARM, but the difference
> is that FLARM is a developed product whereas ADS-B is still 5 - 15
> years away.
>
> --Noel
>
The problem with PowerFlarm is that it does not include ADS-B Out. As a
result, it doesn't reliably receive any ADS-B in traffic data from a
ground station. If this was a true ADS-B In and Out solution, it would
be great, but it is not.

As far as ADS-B being 5-15 years out, that is a complete misconception.
Navworx is currently shipping their ADS-B transceiver, which includes
ADS-B In and Out. The entire east coast already has ADS-B ground
station coverage. The ground station rollout for the entire country
should be completed by the end of 2012.

--
Mike Schumann

noel.wade

August 10th 10, 08:22 PM

On Aug 10, 12:16*pm, Mike Schumann >
wrote:

> The problem with PowerFlarm is that it does not include ADS-B Out. *As a
> result, it doesn't reliably receive any ADS-B in traffic data from a
> ground station. *If this was a true ADS-B In and Out solution, it would

Mike - Weren't you just debating about flying out of range of ground
stations, when talking about transponders? ADS-B from ground stations
falls into the same category.

In close proximity, I would expect ADS-B Out from another aircraft to
trigger my powerFLARM (ADS-B In) solution directly; no need for a
ground station relay!

--Noel

Darryl Ramm

August 10th 10, 08:38 PM

On Aug 10, 11:34*am, sisu1a > wrote:
> > >How does one extract
> > > the logs?
>
> ...ultimate log extractor:http://www.techfresh.net/wp-content/uploads/2008/05/logging-spider.jpg
>
> FWIW I think the contest rental idea sounds like a great plan, and I'm
> sure the FLARM guys would come down in price for bulk reasons as well
> as the promotional factor.
>
> Beyond discounted units for contest rentals, I think it would be in
> FLARM's interests as well to sell the first hundred or two units in
> USA for a significant discount to get the ball rolling towards
> critical mass.
>
> -Paul

The first 50 (I believe) units are offered at a discount of $1,495 and
I believe the ball is well and truly rolling. I am not sure if there
are any left or not for this discount pre-order, contact a dealer. I
suspect Butterfly/Flarm has pent-up demand worldwide for the
PowerFLARM from people who have been deferring purchase of the
traditional Flarm and other third party Flarm devices. So I'm a bit
dubious of focusing on trying to get discounts etc. I'd much rather
see the primary focus begin on making a contest rules decision ASAP.
Want to really "get the ball rolling", just mandate the damn things.

I think FLARM is a good idea in contests and other situations with
high glider densities, and the SSA and IGC need to seriously look at
mandating them in contests. However for the USA I am worried we don't
get into making this decision more complex than it need be. And I
worry that many of the posts here are heading in that direction. For
example the SSA should not twist itself in knots worrying about rental
units, schemes to offset costs, etc. I hope the SSA rules committee
focus on the safety issue and trying to solve a safety problem we
obviously have and make sure the cost is roughly bearable to most
contest pilots. The "market" can solve the other cases, either though
people or clubs sharing units or maybe somebody buying a handful of
units and renting them. Please don't get stuck trying to solve bigger
more complex problems that distract from the core issue. Focus now on
making the right decision for safety and making it ASAP so pilots
going into next year know what is happening. A quick decision will let
product ordering, and those other "market" forces happen more
smoothly. And the SSA does not worry about renting etc. of required
items like flight recorders or parachutes and most contest pilots own
their own but others certainly rent, borrow, use club equipment etc.
those to get by.

For similar sentiments of trying to keep things simple and focus in
making the right decision. I don't think it really helps our needs to
be thinking about involving AOPA or finding other creative markets for
Flarm. Involve AOPA? Why? We don't need advocates or other things
outside our own sport right now. We need to make adoption/rule
decisions asap and let pilots know what is happening. AOPA's position
on technology in this area related to ADS-B is also unfortunately
confused enough already but I don't want to get sidetracked on that
here. At the core of the mess with ADS-B is that it is a technology
that means so many different things to different potential users and
suffers from being this flying kitchen sink. Here we have a technology
developed for and likely the only realistic option for greatly
reducing the glider-on-glider contest collision risk. Run forward with
it, not sideways.

Darryl

Mike Schumann

August 10th 10, 08:41 PM

On 8/9/2010 8:51 AM, Dave Nadler wrote:
> On Aug 9, 9:43 am, Steve > wrote:
>> Curious about the use of Flarm in the US. Was told by another pilot
>> that the frequency used by Flarm is not approved for that category of
>> use in the US. Is that true? If it is, do they make units that use a
>> US approved frequency?
>
> powerflarm units for use in USA will be available later this year.
> older flarm units are not for use in USA.
>
> See: http://www.powerflarm.aero/
>
> Hope that helps,
> Best Regards, Dave "YO electric"

The PowerFlarm specs specify that they transmit on 868 MHz. Is this
frequency permitted in the US?

--
Mike Schumann

Greg Arnold

August 10th 10, 09:20 PM

On 8/10/2010 11:04 AM, noel.wade wrote:
> Sorry to spam the thread. Just noticed on the Craggy website that the
> powerFLARM _does_ include IGC flight logging. Cool!
>
> http://www.craggyaero.com/powerflarm.htm
>
> --Noel

Hmmm, the PowerFLARM website does not mention this feature.

Darryl Ramm

August 10th 10, 09:29 PM

On Aug 10, 12:41*pm, Mike Schumann >
wrote:
> On 8/9/2010 8:51 AM, Dave Nadler wrote:
>
> > On Aug 9, 9:43 am, Steve > *wrote:
> >> Curious about the use of Flarm in the US. Was told by another pilot
> >> that the frequency used by Flarm is not approved for that category of
> >> use in the US. Is that true? If it is, do they make units that use a
> >> US approved frequency?
>
> > powerflarm units for use in USA will be available later this year.
> > older flarm units are not for use in USA.
>
> > See:http://www.powerflarm.aero/
>
> > Hope that helps,
> > Best Regards, Dave "YO electric"
>
> The PowerFlarm specs specify that they transmit on 868 MHz. *Is this
> frequency permitted in the US?
>
> --
> Mike Schumann

What you think FLARM have not thought of that?

Be a bit careful readying the PowerFLARM web site, it's clearly
focused on the European market.

PowerFLARM will operate on a different frequency in the USA than
Europe. Flarm already operates on a different frequencies in
Australia, New Zealand and the rest of the world. Flarm has had a 915
Mhz frequency planned for use the USA for quite a while, although I
don't know if that is the final decision or not. And current units
have neat automatic frequency section based on location. I don't know
for sure if PowerFLARM will do the automatically location based
frequency change but I've been told by the US distributor that units
purchased here will definitely run overseas (for example for traveling
contest pilots).

Darryl

Mike Schumann

August 10th 10, 09:31 PM

On 8/10/2010 2:22 PM, noel.wade wrote:
> On Aug 10, 12:16 pm, Mike >
> wrote:
>
>> The problem with PowerFlarm is that it does not include ADS-B Out. As a
>> result, it doesn't reliably receive any ADS-B in traffic data from a
>> ground station. If this was a true ADS-B In and Out solution, it would
>
> Mike - Weren't you just debating about flying out of range of ground
> stations, when talking about transponders? ADS-B from ground stations
> falls into the same category.
>
> In close proximity, I would expect ADS-B Out from another aircraft to
> trigger my powerFLARM (ADS-B In) solution directly; no need for a
> ground station relay!
>
> --Noel
>

If the other traffic is equipped with ADS-B UAT (the FAA recommendation
for GA), and you our not within range of a ground station, PowerFLARM
will not see him.

--
Mike Schumann

Darryl Ramm

August 10th 10, 09:55 PM

On Aug 10, 1:31*pm, Mike Schumann >
wrote:
> On 8/10/2010 2:22 PM, noel.wade wrote:
>
>
>
> > On Aug 10, 12:16 pm, Mike >
> > wrote:
>
> >> The problem with PowerFlarm is that it does not include ADS-B Out. *As a
> >> result, it doesn't reliably receive any ADS-B in traffic data from a
> >> ground station. *If this was a true ADS-B In and Out solution, it would
>
> > Mike - Weren't you just debating about flying out of range of ground
> > stations, when talking about transponders? *ADS-B from ground stations
> > falls into the same category.
>
> > In close proximity, I would expect ADS-B Out from another aircraft to
> > trigger my powerFLARM (ADS-B In) solution directly; no need for a
> > ground station relay!
>
> > --Noel
>
> If the other traffic is equipped with ADS-B UAT (the FAA recommendation
> for GA), and you our not within range of a ground station, PowerFLARM
> will not see him.
>
> --
> Mike Schumann

Noel.

Read my earlier post in this thread that describes things needed for
ADS-R and TIS-B to work. The ADS-B dual-link design in the USA should
be a concern for us. The scary scenario is say running a ridge where
fully equipped UAT and ADS-B 1090ES just will not "see" each other
outside of GBT (ground station coverage). The GBT coverage will be
pretty impressive compared to say current SSR coverage but is just not
necessarily intended to say provide low level or close to terrain
coverage in places we might care about. This is one reason I don't
believe ADS-B technology alone in the USA can meet our needs until
somebody develops a dual-link layer receiver. Alternately different
locations might adopt UAT or 1090ES technology. I suspect what will
really happen shorter term is people will adopt PowerFLARM and rely
mostly on the flarm-flarm protocol to provide help with that type of
ridge running scenario and use the ADS-B stuff more for visibility of
GA and airline traffic (i.e. think of the ADS-B receiver stuff more as
a fancy enhancement of current PCAS capabilities).

The dual-link issue also affects the ability to track other gliders
over long ranges, that will work fairly well (and an interesting/
useful capability of ADS-B in general) if both gliders are on the same
link layer, but if one is a UAT and the other is on 1090ES the ground
infrastructure won't perform ADS-R unless the gliders are within each
other's service volume or the service volumes of similarly equipped
aircraft (I believe +/- 3,500' and 15 nm range). So your glider
buddies may appear and disappear off the traffic display at times.

Darryl

noel.wade

August 10th 10, 10:19 PM

So if I'm reading Darryl and Mike correctly: The bottom-line is that
the different ADS-B options and reliance on ground-based coverage mean
that FLARM-to-FLARM communications are really the only solid solution
for collision-avoidance when close to terrain or out of ground-based-
coverage areas.

(Mike - before you reply and push the Navworx box yet again, please
prepare an explanation of how the Navworx unit gets around the very
same UAT versus 1090ES issue that you described moments ago. If UAT
and 1090ES don't talk to each other from aircraft-to-aircraft, then it
doesn't matter whether you run a powerFLARM or Navworx box - you're
going to miss out on some of the ADS-B traffic either way.)

--Noel

Mike Schumann

August 10th 10, 10:38 PM

On 8/10/2010 3:29 PM, Darryl Ramm wrote:
> On Aug 10, 12:41 pm, Mike >
> wrote:
>> On 8/9/2010 8:51 AM, Dave Nadler wrote:
>>
>>> On Aug 9, 9:43 am, Steve > wrote:
>>>> Curious about the use of Flarm in the US. Was told by another pilot
>>>> that the frequency used by Flarm is not approved for that category of
>>>> use in the US. Is that true? If it is, do they make units that use a
>>>> US approved frequency?
>>
>>> powerflarm units for use in USA will be available later this year.
>>> older flarm units are not for use in USA.
>>
>>> See:http://www.powerflarm.aero/
>>
>>> Hope that helps,
>>> Best Regards, Dave "YO electric"
>>
>> The PowerFlarm specs specify that they transmit on 868 MHz. Is this
>> frequency permitted in the US?
>>
>> --
>> Mike Schumann
>
> What you think FLARM have not thought of that?
>
> Be a bit careful readying the PowerFLARM web site, it's clearly
> focused on the European market.
>
> PowerFLARM will operate on a different frequency in the USA than
> Europe. Flarm already operates on a different frequencies in
> Australia, New Zealand and the rest of the world. Flarm has had a 915
> Mhz frequency planned for use the USA for quite a while, although I
> don't know if that is the final decision or not. And current units
> have neat automatic frequency section based on location. I don't know
> for sure if PowerFLARM will do the automatically location based
> frequency change but I've been told by the US distributor that units
> purchased here will definitely run overseas (for example for traveling
> contest pilots).
>
> Darryl

I am very careful in reading the PowerFlarm web site. No where is there
any indication that the information provided is European only and that
US models are different.

My whole message here is that people need to VERY carefully research
everything, as all of the options available, now or in the future, have
their own quirks and limitations. No one should assume anything that
isn't clearly documented.

--
Mike Schumann

Mike Schumann

August 10th 10, 10:46 PM

On 8/10/2010 4:19 PM, noel.wade wrote:
> So if I'm reading Darryl and Mike correctly: The bottom-line is that
> the different ADS-B options and reliance on ground-based coverage mean
> that FLARM-to-FLARM communications are really the only solid solution
> for collision-avoidance when close to terrain or out of ground-based-
> coverage areas.
>
> (Mike - before you reply and push the Navworx box yet again, please
> prepare an explanation of how the Navworx unit gets around the very
> same UAT versus 1090ES issue that you described moments ago. If UAT
> and 1090ES don't talk to each other from aircraft-to-aircraft, then it
> doesn't matter whether you run a powerFLARM or Navworx box - you're
> going to miss out on some of the ADS-B traffic either way.)
>
> --Noel
>

The UAT vs 1090ES situation is a huge mess that the FAA has created.
Adding FLARM into the mix doesn't make it any easier (we now have 3
different systems that can't see each other).

It's frustrating that the FLARM guys can't just adapt their box to be
ADS-B UAT compliant (both in Frequency and Protocol) when deployed in
the US. That would eliminate 1/2 (or 1/3rd) of the problem and give
them a blockbuster product they could sell to the entire GA community,
not just the glider market.

Ultimately, the only likely solution to the low level collision
avoidance problem is that all ADS-B transceivers are going to have to
receive both UAT and 1090ES, or UAT is going to have to disappear from
the equation.

--
Mike Schumann

Andrzej Kobus

August 10th 10, 11:01 PM

Has anyone noticed how big this unit is? It is way too big to fit
anywhere in my glider considering I already have a big moving map in
my panel.

FLARM on the ridge is a very good idea, but how many pilots will put a
unit in for FLARM to be effective as a system.

I like the idea of renting FLARM at contests where they are needed the
most, but I would be totally against a FLARM unit that does not have a
voice synthesizer. Looking at the darn display while in a thermal is
asking for trouble.

I would like to try the unit, but I am not ready to buy unless I see
it working in a real situation.

Darryl Ramm

August 10th 10, 11:31 PM

On Aug 10, 3:01*pm, Andrzej Kobus > wrote:
> Has anyone noticed how big this unit is? It is way too big to fit
> anywhere in my glider considering I already have a big moving map in
> my panel.
>
> FLARM on the ridge is a very good idea, but how many pilots will put a
> unit in for FLARM to be effective as a system.
>
> I like the idea of renting FLARM at contests where they are needed the
> most, but I would be totally against a FLARM unit that does not have a
> voice synthesizer. Looking at the darn display while in a thermal is
> asking for trouble.
>
> I would like to try the unit, but I am not ready to buy unless I see
> it working in a real situation.

Be careful "big" means something different to lots of people. And I
personally think the photos of the device look huge on the Butterfly/
PowerFLARM web site. They seem to look much smaller in real life, at
least to me.

The specs are

Height: 46mm / 1.8"
Width: 96mm / 3.8"
Length: 94mm / 3.7"

As I mentioned before one way to visualize this is very roughly two
Zaon MRX stacked on top of each other. The device is looks intended to
be most often installed on top of an instrument panel.

Personally I'd still like it a bit smaller and trade off the internal
space for needed for AA batteries.

Flarm's approach to displays is to display a clear warning pointing to
where the threat is, not having people look at a display of moving map
symbols trying to work out what is going on. So its supposed to be a
glance and then eyes outside. To me that's no different to my PCAS
firing and glancing at the display quickly to see the threat aircraft
altitude difference. I have had some feedback from instructors using
more advanced Flarm displays however where they report some students
do fixate on the displays too much. Something that is harder to do
with a simple Flarm unit.

Their web site says voice warnings are is coming as an upgrade.

I'd be scared to death thinking I'm in a big gaggle with other gliders
where many of the pilots are using Flarm for the first time. Working
out what different tones and displays etc. mean.

Darryl

noel.wade

August 11th 10, 01:28 AM

To repeat what Darryl said about the size:

The website pics are closeups. The SD card slot you see is a Micro-SD
card.

It is 1.8" thick, and about 3.8" in its other dimensions.
For a size reference: the long edge of a deck of playing cards is
about 3.5" long.

--Noel

Andreas Maurer

August 11th 10, 01:52 AM

On Tue, 10 Aug 2010 11:21:00 -0700 (PDT), Tuno >
wrote:

>Andy --
>
>I'm unable to load the FLARM web page to investigate, but I'm curious
>about "intelligent alerting based on glider flight characteristics."

>Can you (or anyone) confirm that PowerFLARMs would have detected (and
>warned) last week's head-on in Uvalde?

Definitely.

>What glider flight characteristics in particular play into FLARM's
>algorithms?

Flarm predicts the flightpath, therefore even allowing a
collision-.probability-analysis of two gliders who are flying slightly
different turns in the same thermal.

Works amazingly well in real life.

Andreas

Andreas Maurer

August 11th 10, 02:03 AM

On Tue, 10 Aug 2010 12:45:25 -0500, Mike Schumann
> wrote:

>FLARM does you no good, if the aircraft that you are about to hit
>doesn't have FLARM installed. No one is suggesting that you not be able
>to buy FLARM. It's just not going to do you any good if the other
>aircraft flying in your area are also not FLARM equipped.
>
>If you are flying in a remote area, with a couple of other glider pilots
>and you all buy FLARM, you have protection from each other, but not the
>stray GA pilot who may wander thru the area. That may be good enough
>for you and if you have a small enough group, you may be able to
>convince everyone to buy a unit.
>
>If you are flying near a major metro area, there is absolutely no way
>you are going to get everyone in the area to invest in FLARM. In that
>environment, you will also probably be flying within range of an ADS-B
>ground station, so investing in ADS-B is definitely the way to go. Not
>only will you see other ADS-B equipped aircraft, but you also will see
>all other Mode C/S transponder equipped aircraft that show up on ATC radar.

Well Mike,

your parachute only helps in very few accident scenarios.
Why do you carry one? Why don't you simply fly withoput one and wait
until you get the glider zero/zero ejection seat that will save you
from a spin half a second before impact?

Noone doubts that Flarm is not the final solution to the US market
(althout Power Flarm comes close) - but with Flarm Chris would still
be alive, and the other midair that might have cost the lives of two
other pilots wouldn't have happened either.

Provocatively spoken:
Isn't it better to save a few lifes than not even trying to?

Andreas

Andreas Maurer

August 11th 10, 02:10 AM

On Tue, 10 Aug 2010 11:34:21 -0700 (PDT), sisu1a
> wrote:

>> >How does one extract
>> > the logs?
>
>...ultimate log extractor: http://www.techfresh.net/wp-content/uploads/2008/05/logging-spider.jpg
>
>FWIW I think the contest rental idea sounds like a great plan, and I'm
>sure the FLARM guys would come down in price for bulk reasons as well
>as the promotional factor.
>
>Beyond discounted units for contest rentals, I think it would be in
>FLARM's interests as well to sell the first hundred or two units in
>USA for a significant discount to get the ball rolling towards
>critical mass.

Paul, believe me:
Anyone who has ever flown with Flarm in glider-crowded airspace (read:
competition) is going to buy one. There is absolutely no need to sell
the first units for a discount price.

People in Europe were very sceptical in the beginning, too. Nowadays
coverage is very close to 100 percent.

Experiencing Flarm in action is very, very convincing.

Andreas

Dave Nadler

August 11th 10, 02:24 AM

On Aug 10, 2:46*pm, Chris Nicholas > wrote:
> My understanding is that Flarm uses a pressure capsule anyway for
> height information, not GPS height.

That is incorrect.
The flarm collision avoidance system uses GPS
for both position and altitude.

Best Regards, Dave

Dave Nadler

August 11th 10, 02:29 AM

On Aug 10, 2:19*pm, T8 > wrote:
> On Aug 10, 2:04*pm, "noel.wade" > wrote:
>
> > Sorry to spam the thread. *Just noticed on the Craggy website that the
> > powerFLARM _does_ include IGC flight logging. *Cool!
>
> >http://www.craggyaero.com/powerflarm.htm
>
> > --Noel
>
> Details, please, if anyone has them. *It seems unlikely that it would
> include an aneroid altimeter or engine run monitor... perhaps it is
> good enough to be a backup logger for comp use? *How does one extract
> the logs?
>
> -T8

Powerflarm for USA will include:

IGC logging (but not world record level).
uSD card.
optional engine noise sensor for guys like me.

Hope that helps,
Best Regards, Dave

August 11th 10, 02:37 AM

On Aug 10, 10:51*am, Mike Schumann >
wrote:
> If you are flying in a remote area, outside of radar coverage, there is
> a very good chance that a transponder equipped aircraft will not be
> interrogated on a regular basis, and, as a result, will NOT show up on
> PowerFlarm or other PCAS type units.

So how much would it cost to build a transponder "interrogator"?
Probably a pittance.

I'm sure someone could have a product ready to ship within a few
months and it would just work in our current system.

Of course, the FAA and FCC would have to get involved, then the
lawyers, etc, etc.... So it would probably be approved for use
sometime around 2025 and cost $5000. Sigh.....

-Tom

Morgans[_2_]

August 11th 10, 03:09 AM

"5Z" > wrote

So how much would it cost to build a transponder "interrogator"?
Probably a pittance.

I'm sure someone could have a product ready to ship within a few
months and it would just work in our current system.

Of course, the FAA and FCC would have to get involved, then the
lawyers, etc, etc.... So it would probably be approved for use
sometime around 2025 and cost $5000. Sigh.....
)))))))))))))))))))))))))))))))))))))))))))))))))
I have wondered that same thing.

I suppose a club could get together and place one on a hilltop or two. to
cover blank areas. If everyone had one in their craft, I suppose it might
get a bit congested with two many interrigations on top of each other at a
busy contest. Would that be a problem or not, I don't know?

So what would be required to get, as far as permission, technical
specifications for a unit, and other things I didn't think of? Any FAA or
other guru's that know about such things out there lurking?
--
Jim in NC

Darryl Ramm

August 11th 10, 03:29 AM

On Aug 10, 7:09*pm, "Morgans" > wrote:
> "5Z" > wrote
>
> So how much would it cost to build a transponder "interrogator"?
> Probably a pittance.
>
> I'm sure someone could have a product ready to ship within a few
> months and it would just work in our current system.
>
> Of course, the FAA and FCC would have to get involved, then the
> lawyers, etc, etc.... *So it would probably be approved for use
> sometime around 2025 and cost $5000. * Sigh.....
> )))))))))))))))))))))))))))))))))))))))))))))))))
> *I have wondered that same thing.
>
> I suppose a club could get together and place one on a hilltop or two. to
> cover blank areas. *If everyone had one in their craft, I suppose it might
> get a bit congested with two many interrigations on top of each other at a
> busy contest. *Would that be a problem or not, I don't know?
>
> So what would be required to get, *as far as permission, technical
> specifications for a unit, and other things I didn't think of? *Any FAA or
> other guru's that know about such things out there lurking?
> --
> Jim in NC

Tom - Airborne interrogators start at about $10k or so now, they are
called TAS or TCAD systems (although some vendors used to confuse TCAD
and PCAS systems). The Garmin GTS 800 series and L3 Skywatch are
leading systems used in GA aircraft. The high-end version of these
systems are effectively TCAS I (but not II) systems. And these systems
are all adding ADS-B 1090ES data-in capability to complement the
active interrogation. You could pull the engine out of your 26E and
make it an avionics bay...

One challenge with these system is the interrogator consuming power A
low power system for just pinging really nearby glider transponders
could reduce that but then you would start running into how complex
these systems really are. Even not wanting directional data the system
may need to do some form of the sophisticated whisper-shout scheme
developed originally in TCAS systems to minimize overlapping
transponder replies. The real reason it won't happen is it is a lot of
complexity and certification costs with no real future benefit to most
people - and by the time you tried to develop this at huge cost most
everybody with a transponder would have gone ADS-B.And even though
that has lots of holes in its story its going to do the job good
enough for most people.

--

Jim - As for fixed interrogators I hope you are joking right? The
cheapest available ground based systems are multilateration systems.
These things are not consumer electronics and you don't get to slap
something together and start transmitting on 1030MHz. How many $M
budget do you have?

---

To the original statement, we need to be careful what is meant by "a
remote area". For those of use who fly with PCAS we know that
transponders in threat aircraft can get interrogated in lots of places
including areas that seem very remote. Interrogators include civil and
military approach and area radars, airborne TCAS and TCAD/TAS systems
and presumably in a few places ground based multilateration systems. I
was pretty surprised in how many places you do get interrogated. But
its often when you get low or in the shadow of a mountain or down in a
valley that this cuts out. And its really important for pilots why fly
with PCAS systems to know its dependent on external interrogators and
get a feel for where it does and does not work where they fly.

Darryl

Mike Schumann

August 11th 10, 04:38 AM

On 8/10/2010 8:03 PM, Andreas Maurer wrote:
> On Tue, 10 Aug 2010 12:45:25 -0500, Mike Schumann
> > wrote:
>
>
>> FLARM does you no good, if the aircraft that you are about to hit
>> doesn't have FLARM installed. No one is suggesting that you not be able
>> to buy FLARM. It's just not going to do you any good if the other
>> aircraft flying in your area are also not FLARM equipped.
>>
>> If you are flying in a remote area, with a couple of other glider pilots
>> and you all buy FLARM, you have protection from each other, but not the
>> stray GA pilot who may wander thru the area. That may be good enough
>> for you and if you have a small enough group, you may be able to
>> convince everyone to buy a unit.
>>
>> If you are flying near a major metro area, there is absolutely no way
>> you are going to get everyone in the area to invest in FLARM. In that
>> environment, you will also probably be flying within range of an ADS-B
>> ground station, so investing in ADS-B is definitely the way to go. Not
>> only will you see other ADS-B equipped aircraft, but you also will see
>> all other Mode C/S transponder equipped aircraft that show up on ATC radar.
>
> Well Mike,
>
> your parachute only helps in very few accident scenarios.
> Why do you carry one? Why don't you simply fly withoput one and wait
> until you get the glider zero/zero ejection seat that will save you
> from a spin half a second before impact?
>
>
> Noone doubts that Flarm is not the final solution to the US market
> (althout Power Flarm comes close) - but with Flarm Chris would still
> be alive, and the other midair that might have cost the lives of two
> other pilots wouldn't have happened either.
>
> Provocatively spoken:
> Isn't it better to save a few lifes than not even trying to?
>
>
> Andreas
>

The same statement applies to ADS-B. If Chris had been the only glider
there with FLARM installed, nothing would have changed.

--
Mike Schumann

Eric Greenwell

August 11th 10, 05:21 AM

On 8/10/2010 10:51 AM, Mike Schumann wrote:
>
> If you are flying in a remote area, outside of radar coverage, there
> is a very good chance that a transponder equipped aircraft will not be
> interrogated on a regular basis, and, as a result, will NOT show up on
> PowerFlarm or other PCAS type units.
>
My experience in places so remote my transponder is not interrogated
suggests there are so few other aircraft nearby my collision risk is
very small.

Over the eight years I've had my transponder, I've flown in many
different areas, most of them in the western half of the USA, but a few
on the eastern side, and I can't remember any area were the transponder
didn't get interrogated. In some places, it was infrequent (every 10 to
20 seconds, say) at times, particularly close to a mountain and below
the top.

So, I'm willing to take my chances with a solution that doesn't work
where no interrogations occur.

--
Eric Greenwell - Washington State, USA (netto to net to email me)

- "Transponders in Sailplanes - Feb/2010" also ADS-B, PCAS, Flarm http://tinyurl.com/yb3xywl

- "A Guide to Self-launching Sailplane Operation Mar/2004" Much of what you need to know tinyurl.com/yfs7tnz

Brad[_2_]

August 11th 10, 05:29 AM

On Aug 10, 9:21*pm, Eric Greenwell > wrote:
> On 8/10/2010 10:51 AM, Mike Schumann wrote:
>
> > If you are flying in a remote area, outside of radar coverage, there
> > is a very good chance that a transponder equipped aircraft will not be
> > interrogated on a regular basis, and, as a result, will NOT show up on
> > PowerFlarm or other PCAS type units.
>
> My experience in places so remote my transponder is not interrogated
> suggests there are so few other aircraft nearby my collision risk is
> very small.
>
> Over the eight years I've had my transponder, I've flown in many
> different areas, most of them in the western half of the USA, but a few
> on the eastern side, and I can't remember any area were the transponder
> didn't get interrogated. In some places, it was infrequent (every 10 to
> 20 seconds, say) at times, particularly close to a mountain and below
> the top.
>
> So, I'm willing to take my chances with a solution that doesn't work
> where no interrogations occur.
>
> --
> Eric Greenwell - Washington State, USA (netto to net to email me)
>
> - "Transponders in Sailplanes - Feb/2010" also ADS-B, PCAS, Flarmhttp://tinyurl.com/yb3xywl
>
> - "A Guide to Self-launching Sailplane Operation Mar/2004" Much of what you need to know tinyurl.com/yfs7tnz

I bought a PowerFlarm today.............now it's up to my flying
buddies to do the same thing.

Brad

Eric Greenwell

August 11th 10, 05:30 AM

On 8/9/2010 10:54 PM, Bob wrote:
>
> Mike
>
> The "Flarm Guys" wanted to go to the US market when they first came
> out but were advised by legal counsel in the US that they would have
> "severe" liability problems. They are a small company, just 2 guys at
> first. I am from the US and fly in a German club and when Flarm first
> came out with the "No US citizens" codicil in the OpMan it was some
> concern for the club. It hasn't been a problem so far and I would not
> fly without a Flarm unit period! We have 100% compliance at our club.
> I don't know what the numbers are for Germany, Italy, Austria,
> Switzerland and France (the countries whose pilots I meet on a typical
> Alps flight) but it appears quite high. Also the hang glider/
> paraglider crowd is on board.
> When I come back to the States eventually I hope Flarm/Pwr Flarm has
> saturated the soaring market. It is the only way I'll be able to fly.
>
You may be pleased to learn there are many good soaring areas in the
country where the glider density is so low, colliding with another
glider is the least of your worries. In fact, that is a - maybe "the" -
major reason that Flarm is not popular in the USA. Flarm was developed
where the glider density is many times that of the USA, because there
are many more gliders, and much less airspace.

--
Eric Greenwell - Washington State, USA (netto to net to email me)

- "Transponders in Sailplanes - Feb/2010" also ADS-B, PCAS, Flarm http://tinyurl.com/yb3xywl

- "A Guide to Self-launching Sailplane Operation Mar/2004" Much of what you need to know tinyurl.com/yfs7tnz

Steve Leonard[_2_]

August 11th 10, 05:57 AM

On Aug 10, 11:29*pm, Brad > wrote:
>
> I bought a PowerFlarm today.............now it's up to my flying
> buddies to do the same thing.
>
> Brad- Hide quoted text -
>

Good for you, Brad! I placed my order back in January. Still
wondering what the rest of you guys are waiting for? And I don't want
to hear the excuse of "I won't buy one until after I have seen one and
gotten to use it." How many of you have plunked down TONS more money
than that before the prototype of your new LS-23 had even flown?
Thanks for the suggestion, Ed Kilbourne! You don't have to wait until
there is a rule to buy a piece of safety enhancing equipment. Even if
it isn't our perfect solution, it is a hell of a lot better than just
your eyes.

FLARM is coming to the US, Mike, so please do your best to accept it
and stop trying to say it is just another distraction that is going to
further delay this "ultimate" system that the government is
designing. Then three years from that date, he says "Just one more
wait..."

Steve Leonard

Alan[_6_]

August 11th 10, 05:58 AM

In article > Eric Greenwell > writes:
>On 8/10/2010 10:51 AM, Mike Schumann wrote:
>>
>> If you are flying in a remote area, outside of radar coverage, there
>> is a very good chance that a transponder equipped aircraft will not be
>> interrogated on a regular basis, and, as a result, will NOT show up on
>> PowerFlarm or other PCAS type units.
>>
>My experience in places so remote my transponder is not interrogated
>suggests there are so few other aircraft nearby my collision risk is
>very small.
>
>Over the eight years I've had my transponder, I've flown in many
>different areas, most of them in the western half of the USA, but a few
>on the eastern side, and I can't remember any area were the transponder
>didn't get interrogated. In some places, it was infrequent (every 10 to
>20 seconds, say) at times, particularly close to a mountain and below
>the top.
>
>So, I'm willing to take my chances with a solution that doesn't work
>where no interrogations occur.

A reasonable point. There is a lot of little used space to fly in.

As someone who started as a power pilot, I still find it hard to imagine
how one would be willing to fly in such close proximity to other aircraft
that you cannot continuously see.

"Cessna 123, traffic at your 3 o'clock, one mile, same direction" gets
my attention.

"glider 45, traffic at your 6 to 7 o'clock, 50 yards behind, 100 feet
above, circling in same direction" sounds terrifying. (I am in a blind
spot for him, and he is in one for me.)

I worry enough about a plane a mile away in a traffic pattern. Not having
continuous visual separation at 50 yards distance scares me.

I don't think the proprietary flarm system is the answer (being a fan of
open standards). I would much prefer spending my time where the only other
traffic is likely to be a bird, and enjoying the view.

Alan

Brad[_2_]

August 11th 10, 06:17 AM

On Aug 10, 9:57*pm, Steve Leonard > wrote:
> On Aug 10, 11:29*pm, Brad > wrote:
>
>
>
> > I bought a PowerFlarm today.............now it's up to my flying
> > buddies to do the same thing.
>
> > Brad- Hide quoted text -
>
> Good for you, Brad! *I placed my order back in January. *Still
> wondering what the rest of you guys are waiting for? *And I don't want
> to hear the excuse of "I won't buy one until after I have seen one and
> gotten to use it." *How many of you have plunked down TONS more money
> than that before the prototype of your new LS-23 *had even flown?
> Thanks for the suggestion, Ed Kilbourne! *You don't have to wait until
> there is a rule to buy a piece of safety enhancing equipment. *Even if
> it isn't our perfect solution, it is a hell of a lot better than just
> your eyes.
>
> FLARM is coming to the US, Mike, so please do your best to accept it
> and stop trying to say it is just another distraction that is going to
> further delay this "ultimate" system that the government is
> designing. *Then three years from that date, he says "Just one more
> wait..."
>
> Steve Leonard

Thanks Steve, I think it's a good move. I know as far as sailplanes
are concerned the more of my glider buddies that use the them the
better, I need to study more on how it will help with power traffic,
but anything to help me "see" what's out there has to be a good start.

Also............I lost a friend in a mid air a few years
ago...........I'll share 2 things: I dug his transponder antenna out
of a 3 foot hole in the ground, it's now sticking out of the top of a
tree trunk his glider snapped off as it's crashed thru the
trees..........the other; seeing your friend strapped to a backboard
at the end of a rope under a helicopter is something I NEVER want to
experience again.

Yes, buying Flarm was a good move for me.

Brad

Chris Nicholas[_2_]

August 11th 10, 06:50 AM

Dave N, I just read what is on the web, and my Flarm had a pressure
capsule AIUI before I had the IGC logger function retrofitted.

From http://www.lxavionics.co.uk/flarm.htm :

“Flarm consists of a very low power RF transmitter (868.2 MHz) with a
range of 2- 3 Km that continuously broadcasts its position and
velocity vector derived from its integrated GPS receiver. It uses a
combination of a barometric altitude sensor and GPS derived altitude
for determining proximity and flight path. In parallel it receives any
signals from nearby Flarm equipped aircraft . . . ”

Anyway, the important thing is that its collision alert algorithm
seems pretty good, but not perfect, and at least one person has
reported that the height difference shown (is the threat higher,
lower, or at your level) can sometimes be in the wrong direction – but
only when it is almost on your level anyway.

I don't find that surprising. We are sensitive to height differences
of a few feet. Neither barometric capsules nor GPS height are that
accurate. But GPS height as determined by two units very close to each
other are probably subjected to a very similar if not identical error
in height calculation, so the differences are probably small compared
with the absolute height tolerance.

Regards - Chris N.

noel.wade

August 11th 10, 07:45 AM

On Aug 10, 9:58*pm, (Alan) wrote:

> I would much prefer spending my time where the only other
> traffic is likely to be a bird, and enjoying the view.
>
> * * * * Alan

Alan - The flaw in that logic is that you cannot control who choses to
fly close to YOU or your location! You can try to hide, but if you
can get to a certain place with your glider, chances are that other
aircraft are capable of reaching that location as well.

I'm not trying to be mean or say that you have to like gaggle-flying
or the FLARM device; I'm just saying that a "head in the sand"
attitude isn't a substitute for protection.

--Noel

August 11th 10, 12:50 PM

On Aug 11, 12:29*am, Brad > wrote:

> I bought a PowerFlarm today.............now it's up to my flying
> buddies to do the same thing.

I'm just about ready to pull the trigger on this, myself.

Did you have to put down a deposit? And is the 'discount' price still
available?

-Evan

John Cochrane

August 11th 10, 01:04 PM

> You may be pleased to learn there are many good soaring areas in the
> country where the glider density is so low, colliding with another
> glider is the least of your worries. In fact, that is a - maybe "the" -
> major reason that Flarm is not popular in the USA.

A national contest is not one of them. There, colliding with another
glider is undoubtedly one of your major worries. I think this
realization is moving the contest community towards Flarm. It may
make sense for contest gliders, and those operating in high glider
traffic areas (Whites, Ridges) to get Flarm, recreational gliders
operating in low glider but high power traffic airspace to get
transponders and Pcas, and lucky guys out in the middle of nowhere to
simply open eyeballs.

John Cochrane

Westbender

August 11th 10, 03:41 PM

Forgive me if this is a really dumb question. I don't know much about
transponder operation.

Is it a technical requirement for a transponder to only transmit when
it's been interrogated by a ping from a remote source? I'm just
wondering why transponders can't have a "timeout" mechanism built into
it where it will automatically report/transmit if it hasn't been
pinged in a certain amount of time. Something like a 30 second
timeout? Maybe user-selectable? For the folks who fly in remote areas,
wouldn't something like this help? Or is the transponder response of
no use without pairing it with a request (ping)?

William Gagen

August 11th 10, 04:07 PM

FLARM - We NEED it yesterday.

How many more midairs do we need to have in our sport?

What if we have a midair with an airliner? Can you say soaring as a
sport is dead, as the FAA will reflexively eliminate all of our
flexibility.

The cost of FLARM in any form is negligible compared to staying
alive.

I have used FLARM at the IMGC Competition (International Military
Glider Comp) in Germany, and it turned a competition with 93 gliders
into the safest competition I have ever flown in anywhere.

It provides timely, accurate, important alerts for collision potential
with very few spurious or distracting warnings. It is vastly superior
to PCAS. There is absolutely no reason we shouldn't be requiring it
for all competition aircraft PERIOD!

The following midairs could all have been prevented by FLARM: Parowan
this summer, Uvalde this summer, Boulder last winter, the Hudson River
helicopter/light plane midair.

Thanks for reading my rant. But, having used it, I know how good it
is, and why we need it yesterday!

SSA could be helpful by providing loaner or rental FLARM units to
aircraft to use in competitions. In this way, we could get them into
every competition sooner. A pilot could rent a unit for say $100 a
competition, and over 2 summers the units would be paid off.

mattm[_2_]

August 11th 10, 04:09 PM

On Aug 11, 10:41*am, Westbender > wrote:
> Forgive me if this is a really dumb question. I don't know much about
> transponder operation.
>
> Is it a technical requirement for a transponder to only transmit when
> it's been interrogated by a ping from a remote source? I'm just
> wondering why transponders can't have a "timeout" mechanism built into
> it where it will automatically report/transmit if it hasn't been
> pinged in a certain amount of time. Something like a 30 second
> timeout? Maybe user-selectable? For the folks who fly in remote areas,
> wouldn't something like this help? Or is the transponder response of
> no use without pairing it with a request (ping)?

That's the meaning of "transponder" -- it transmits a response (to a
radar paint), plus it includes additional information. It goes back
to
WWII days when it was originally known as IFF -- Identify Friend or
Foe. The detection methods based on transponder response depend
on the timing between when the primary pulse is seen and the response.
The larger the duration, the further from the transponder you are.

This is the point of the FLARM scheme -- all the units periodically
broadcast their status, so they are visible even when there is no
radar around.

-- Matt

Westbender

August 11th 10, 04:27 PM

On Aug 11, 10:09*am, mattm > wrote:
> On Aug 11, 10:41*am, Westbender > wrote:
>
> > Forgive me if this is a really dumb question. I don't know much about
> > transponder operation.
>
> > Is it a technical requirement for a transponder to only transmit when
> > it's been interrogated by a ping from a remote source? I'm just
> > wondering why transponders can't have a "timeout" mechanism built into
> > it where it will automatically report/transmit if it hasn't been
> > pinged in a certain amount of time. Something like a 30 second
> > timeout? Maybe user-selectable? For the folks who fly in remote areas,
> > wouldn't something like this help? Or is the transponder response of
> > no use without pairing it with a request (ping)?
>
> That's the meaning of "transponder" -- it transmits a response (to a
> radar paint), plus it includes additional information. *It goes back
> to
> WWII days when it was originally known as IFF -- Identify Friend or
> Foe. *The detection methods based on transponder response depend
> on the timing between when the primary pulse is seen and the response.
> The larger the duration, the further from the transponder you are.
>
> This is the point of the FLARM scheme -- all the units periodically
> broadcast their status, so they are visible even when there is no
> radar around.
>
> -- Matt

When I read the "how it works" on the Zaon website, it says it reads
the response. It doesn't say anything about using the primary pulse in
it's process. Is that typical of PCAS systems?

This is where my question originates. It seems that the PCAS system
might not need the initial request from a radar to evaluate threats.
If so, then wouldn't an aircraft transponder "replying" without a
radar pulse give surrounding aircraft with PCAS the means to detect?

Dave Nadler

August 11th 10, 04:41 PM

On Aug 11, 11:27*am, Westbender > wrote:
> On Aug 11, 10:09*am, mattm > wrote:
>
>
>
> > On Aug 11, 10:41*am, Westbender > wrote:
>
> > > Forgive me if this is a really dumb question. I don't know much about
> > > transponder operation.
>
> > > Is it a technical requirement for a transponder to only transmit when
> > > it's been interrogated by a ping from a remote source? I'm just
> > > wondering why transponders can't have a "timeout" mechanism built into
> > > it where it will automatically report/transmit if it hasn't been
> > > pinged in a certain amount of time. Something like a 30 second
> > > timeout? Maybe user-selectable? For the folks who fly in remote areas,
> > > wouldn't something like this help? Or is the transponder response of
> > > no use without pairing it with a request (ping)?
>
> > That's the meaning of "transponder" -- it transmits a response (to a
> > radar paint), plus it includes additional information. *It goes back
> > to
> > WWII days when it was originally known as IFF -- Identify Friend or
> > Foe. *The detection methods based on transponder response depend
> > on the timing between when the primary pulse is seen and the response.
> > The larger the duration, the further from the transponder you are.
>
> > This is the point of the FLARM scheme -- all the units periodically
> > broadcast their status, so they are visible even when there is no
> > radar around.
>
> > -- Matt
>
> When I read the "how it works" on the Zaon website, it says it reads
> the response. It doesn't say anything about using the primary pulse in
> it's process. Is that typical of PCAS systems?
>
> This is where my question originates. It seems that the PCAS system
> might not need the initial request from a radar to evaluate threats.
> If so, then wouldn't an aircraft transponder "replying" without a
> radar pulse give surrounding aircraft with PCAS the means to detect?

A PCAS system replies on someone else interrogating the
transponders. "Someone" is either a ground radar station or
a TCAS-II equipped aircraft. If you are in a valley without
radar and without overflying jets, you will hear nothing.

Hope that helps,
Best Regards, Dave

August 11th 10, 04:54 PM

On Aug 11, 12:29*am, Brad > wrote:

> I bought a PowerFlarm today.............now it's up to my flying
> buddies to do the same thing.

Ordered mine this morning.

-Evan Ludeman / T8

Westbender

August 11th 10, 04:55 PM

On Aug 11, 10:41*am, Dave Nadler > wrote:
> On Aug 11, 11:27*am, Westbender > wrote:
>
>
>
>
>
> > On Aug 11, 10:09*am, mattm > wrote:
>
> > > On Aug 11, 10:41*am, Westbender > wrote:
>
> > > > Forgive me if this is a really dumb question. I don't know much about
> > > > transponder operation.
>
> > > > Is it a technical requirement for a transponder to only transmit when
> > > > it's been interrogated by a ping from a remote source? I'm just
> > > > wondering why transponders can't have a "timeout" mechanism built into
> > > > it where it will automatically report/transmit if it hasn't been
> > > > pinged in a certain amount of time. Something like a 30 second
> > > > timeout? Maybe user-selectable? For the folks who fly in remote areas,
> > > > wouldn't something like this help? Or is the transponder response of
> > > > no use without pairing it with a request (ping)?
>
> > > That's the meaning of "transponder" -- it transmits a response (to a
> > > radar paint), plus it includes additional information. *It goes back
> > > to
> > > WWII days when it was originally known as IFF -- Identify Friend or
> > > Foe. *The detection methods based on transponder response depend
> > > on the timing between when the primary pulse is seen and the response..
> > > The larger the duration, the further from the transponder you are.
>
> > > This is the point of the FLARM scheme -- all the units periodically
> > > broadcast their status, so they are visible even when there is no
> > > radar around.
>
> > > -- Matt
>
> > When I read the "how it works" on the Zaon website, it says it reads
> > the response. It doesn't say anything about using the primary pulse in
> > it's process. Is that typical of PCAS systems?
>
> > This is where my question originates. It seems that the PCAS system
> > might not need the initial request from a radar to evaluate threats.
> > If so, then wouldn't an aircraft transponder "replying" without a
> > radar pulse give surrounding aircraft with PCAS the means to detect?
>
> A PCAS system replies on someone else interrogating the
> transponders. "Someone" is either a ground radar station or
> a TCAS-II equipped aircraft. If you are in a valley without
> radar and without overflying jets, you will hear nothing.
>
> Hope that helps,
> Best Regards, Dave- Hide quoted text -
>
> - Show quoted text -

Right, did you read my first post?

Since the MRX PCAS (passive) only uses the reply from transponders,
wouldn't it be nice if the trig had a timed/scheduled transmit when
not interrogated for a certain amount of time? If so, a combination of
a trig/PCAS would be relatively inexpensive for glider-to-glider
detection (yeah, yeah, assuming everyone had that combo). The best
part would be the benefits of the "normal" operating mode of the trig
and PCAS in relation to other GA and commercial aircraft.

What are the ramifications of doing something such a thing?

Westbender

August 11th 10, 05:08 PM

On Aug 11, 10:55*am, Westbender > wrote:
> On Aug 11, 10:41*am, Dave Nadler > wrote:
>
>
>
>
>
> > On Aug 11, 11:27*am, Westbender > wrote:
>
> > > On Aug 11, 10:09*am, mattm > wrote:
>
> > > > On Aug 11, 10:41*am, Westbender > wrote:
>
> > > > > Forgive me if this is a really dumb question. I don't know much about
> > > > > transponder operation.
>
> > > > > Is it a technical requirement for a transponder to only transmit when
> > > > > it's been interrogated by a ping from a remote source? I'm just
> > > > > wondering why transponders can't have a "timeout" mechanism built into
> > > > > it where it will automatically report/transmit if it hasn't been
> > > > > pinged in a certain amount of time. Something like a 30 second
> > > > > timeout? Maybe user-selectable? For the folks who fly in remote areas,
> > > > > wouldn't something like this help? Or is the transponder response of
> > > > > no use without pairing it with a request (ping)?
>
> > > > That's the meaning of "transponder" -- it transmits a response (to a
> > > > radar paint), plus it includes additional information. *It goes back
> > > > to
> > > > WWII days when it was originally known as IFF -- Identify Friend or
> > > > Foe. *The detection methods based on transponder response depend
> > > > on the timing between when the primary pulse is seen and the response.
> > > > The larger the duration, the further from the transponder you are.
>
> > > > This is the point of the FLARM scheme -- all the units periodically
> > > > broadcast their status, so they are visible even when there is no
> > > > radar around.
>
> > > > -- Matt
>
> > > When I read the "how it works" on the Zaon website, it says it reads
> > > the response. It doesn't say anything about using the primary pulse in
> > > it's process. Is that typical of PCAS systems?
>
> > > This is where my question originates. It seems that the PCAS system
> > > might not need the initial request from a radar to evaluate threats.
> > > If so, then wouldn't an aircraft transponder "replying" without a
> > > radar pulse give surrounding aircraft with PCAS the means to detect?
>
> > A PCAS system replies on someone else interrogating the
> > transponders. "Someone" is either a ground radar station or
> > a TCAS-II equipped aircraft. If you are in a valley without
> > radar and without overflying jets, you will hear nothing.
>
> > Hope that helps,
> > Best Regards, Dave- Hide quoted text -
>
> > - Show quoted text -
>
> Right, did you read my first post?
>
> Since the MRX PCAS (passive) only uses the reply from transponders,
> wouldn't it be nice if the trig had a timed/scheduled transmit when
> not interrogated for a certain amount of time? If so, a combination of
> a trig/PCAS would be relatively inexpensive for glider-to-glider
> detection (yeah, yeah, assuming everyone had that combo). The best
> part would be the benefits of the "normal" operating mode of the trig
> and PCAS in relation to other GA and commercial aircraft.
>
> What are the ramifications of doing something such a thing?- Hide quoted text -
>
> - Show quoted text -

I'm thinking along the lines of a "passive detection mode" in the
Trig...

Rob[_7_]

August 11th 10, 05:13 PM

>
> Details, please, if anyone has them. *It seems unlikely that it would
> include an aneroid altimeter or engine run monitor... perhaps it is
> good enough to be a backup logger for comp use? *How does one extract
> the logs?
>
> -T8

The original Flarm device appears to have both an ENL sensor and a
pressure altimeter. Don't see the specs for the new Power Flarm.
See:
http://www.fai.org/gliding/system/files/flarm-igc.pdf

V3

Dave Nadler

August 11th 10, 05:21 PM

On Aug 11, 11:55*am, Westbender > wrote:
> On Aug 11, 10:41*am, Dave Nadler > wrote:
>
>
>
> > On Aug 11, 11:27*am, Westbender > wrote:
>
> > > On Aug 11, 10:09*am, mattm > wrote:
>
> > > > On Aug 11, 10:41*am, Westbender > wrote:
>
> > > > > Forgive me if this is a really dumb question. I don't know much about
> > > > > transponder operation.
>
> > > > > Is it a technical requirement for a transponder to only transmit when
> > > > > it's been interrogated by a ping from a remote source? I'm just
> > > > > wondering why transponders can't have a "timeout" mechanism built into
> > > > > it where it will automatically report/transmit if it hasn't been
> > > > > pinged in a certain amount of time. Something like a 30 second
> > > > > timeout? Maybe user-selectable? For the folks who fly in remote areas,
> > > > > wouldn't something like this help? Or is the transponder response of
> > > > > no use without pairing it with a request (ping)?
>
> > > > That's the meaning of "transponder" -- it transmits a response (to a
> > > > radar paint), plus it includes additional information. *It goes back
> > > > to
> > > > WWII days when it was originally known as IFF -- Identify Friend or
> > > > Foe. *The detection methods based on transponder response depend
> > > > on the timing between when the primary pulse is seen and the response.
> > > > The larger the duration, the further from the transponder you are.
>
> > > > This is the point of the FLARM scheme -- all the units periodically
> > > > broadcast their status, so they are visible even when there is no
> > > > radar around.
>
> > > > -- Matt
>
> > > When I read the "how it works" on the Zaon website, it says it reads
> > > the response. It doesn't say anything about using the primary pulse in
> > > it's process. Is that typical of PCAS systems?
>
> > > This is where my question originates. It seems that the PCAS system
> > > might not need the initial request from a radar to evaluate threats.
> > > If so, then wouldn't an aircraft transponder "replying" without a
> > > radar pulse give surrounding aircraft with PCAS the means to detect?
>
> > A PCAS system replies on someone else interrogating the
> > transponders. "Someone" is either a ground radar station or
> > a TCAS-II equipped aircraft. If you are in a valley without
> > radar and without overflying jets, you will hear nothing.
>
> > Hope that helps,
> > Best Regards, Dave- Hide quoted text -
>
> > - Show quoted text -
>
> Right, did you read my first post?
>
> Since the MRX PCAS (passive) only uses the reply from transponders,
> wouldn't it be nice if the trig had a timed/scheduled transmit when
> not interrogated for a certain amount of time? If so, a combination of
> a trig/PCAS would be relatively inexpensive for glider-to-glider
> detection (yeah, yeah, assuming everyone had that combo). The best
> part would be the benefits of the "normal" operating mode of the trig
> and PCAS in relation to other GA and commercial aircraft.
>
> What are the ramifications of doing something such a thing?

You CANNOT do that.
You will never get approval for transmissions on 1090...

Hope that's clear,
Best Regards, Dave

Darryl Ramm

August 11th 10, 05:23 PM

On Aug 11, 8:07*am, William Gagen > wrote:
> FLARM - We NEED it yesterday.
>
> How many more midairs do we need to have in our sport?
>
> What if we have a midair with an airliner? Can you say soaring as a
> sport is dead, as the FAA will reflexively eliminate all of our
> flexibility.
>
> The cost of FLARM in any form is negligible compared to staying
> alive.
>
> I have used FLARM at the IMGC Competition (International Military
> Glider Comp) in Germany, and it turned a competition with 93 gliders
> into the safest competition I have ever flown in anywhere.
>
> It provides timely, accurate, important alerts for collision potential
> with very few spurious or distracting warnings. It is vastly superior
> to PCAS. There is absolutely no reason we shouldn't be requiring it
> for all competition aircraft PERIOD!
>
> The following midairs could all have been prevented by FLARM: Parowan
> this summer, Uvalde this summer, Boulder last winter, the Hudson River
> helicopter/light plane midair.
>
> Thanks for reading my rant. But, having used it, I know how good it
> is, and why we need it yesterday!
>
> SSA could be helpful by providing loaner or rental FLARM units to
> aircraft to use in competitions. In this way, we could get them into
> every competition sooner. A pilot could rent a unit for say $100 a
> competition, and over 2 summers the units would be paid off.

There is a gamut of collision scenarios from glider-glider, glider-
towplane, glider-GA, glider-fast-jet and glider-airliner and there is
no single technology or single product that well addresses all these
problems. The first thing in thinking about collision avoidance is to
be very clear just what problem(s) you are trying to solve.

I agree that Flarm and (and in the USA the flarm-flarm part of
PowerFLARM product) can be a significant help in glide-glider and
glider-towplane collision scenarios and I agree that the collision
with an airliner is a horrible scenario, for the innocent passengers
and crew, and would cause incredible damage to our sport. However
unfortunately this post seems to jumble up too much of all this
collision avoidance/traffic awareness technology and the capabilities
and benefits and that worries me.

The post talks about "flarm" helping with airliner collision avoidance
and that is a dangerous claim to make without some careful
qualification and is certainly not true with with the traditional
flarm product in Europe. Flarm (the flarm-flarm protocol) has nothing
to do with avoiding airliner collisions. Airliners and fast jets (and
most GA traffic outside of say tow planes) just will not be able to
receive or transmit the flarm protocol and the flarm protocol does not
make a glider visible to ATC.

The PowerFLARM product with 1090ES can receiver ADS-B over 1090ES.
Most airliners, fast jets and GA aircraft are not yet equipped with
1090ES data out. Rule for ADS-B equipage vary between Europe and the
USA, all airliners eventually will have 1090ES data-out but I don't
think anybody has good timelines yet for when a significant fraction
of them will be equipped. Once 1090ES data-out equipped a PowerFLARM
would "see" that traffic via 1090ES. The PowerFLARM will "see"
airliner traffic today via PCAS but obviously not get direction
information and PCAS tends to operate at relatively short range for
the fast closure rates involved in a collison with an airliner or fast-
jet. In general it really is a bad idea to think gliders are going to
operate in areas of high-density airline or fast-jet traffic and rely
on PCAS or ADS-B receivers to help provide avoid mid-air collisions.
The closure rates are high, gliders are often invisible to ATC primary
radar, and gliders are incredibly hard to see for those flight crews
even if they are aware/expecting the glider traffic.

In the USA and Europe effectively all airliners, many fast-jets and
many military transpots etc. are TCAS equipped, and many of that is
TCAS II. TCAS II provides those flight crew with mandatory climb/
descent instruction to avoid collisions. These instructions must be
followed and override ATC instructions to the pilot. Flarm and
PowerFLARM do not provide any visibility to TCAS and a TCAS equipped
airliner or fast jet will plow right through a glider equipped with
Flarm or PowerFLARM with no warning. A Mode C or Mode S transponder
is the only device that both provide visibility to ATC radar and to
TCAS systems (and also TAS/TCAD and PCAS systems).

For all these reasons it is important for areas of high density
airline and fast-jet traffic that glider pilots continue to consider
equipping with transponders. It will will be concerning in those area
if say PowerFLARM is seen by some pilots as simple alternative to
transponder adaption.

The post also compares PCAS to Flarm. Many pilots in the USA use PCAS
for awareness of GA traffic and that is not addressed by traditional
Flarm units. The PowerFLARM is interesting in it does includes PCAS
capabilities.

The PCAS and 1090ES receiver capability of the PowerFLARM make it very
interesting to combine with a Mode S transponder with 1090ES data out
capability (like the Trig TT21) and that provides a solution that does
address a wide range of collision scenario. But in the USA even that
system will have issues at times inter-operating with UAT systems in
the dual-line ADS-B system in the USA (e.g. the issues with operating
outside of GBT coverage that I've described before in this thread).

---

I would also be careful claiming Flarm would prevent specific
accidents without a careful analysis. Especially because it is
unlikely that many GA aircraft will equip with a Flarm or PowerFLARM
device. So I'm not sure I claim absolutely that this would prevent the
Colorado mid-air with a Cirrus. PowerFLARM in the glider and tow plane
may have detected the Cirrus via PCAS, the Cirrus transponder may have
been interrogated enough to provide a PCAS alert but you have issues
of PCAS accuracy and false alarms especially if either or both the tow-
plane or glider have transponders. And I am not aware of what if any
traffic awareness system the Cirrus had on board. I not sure Flarm or
PowerFLARM are really relevant to the Hudson river collision, as those
aircraft are just not likely to equip with either product. It is more
likely in future that those aircraft would equip with GA oriented PCAS
or ADS-B data-out and data-in products, if they were both suitably
equipped in future then yes, hopefully that would reduce the chance
for such a collision. PCAS itself may be problematic is some areas
like this because of the high traffic density and high alarm rates.

Darryl

Darryl Ramm

August 11th 10, 05:38 PM

On Aug 11, 8:55*am, Westbender > wrote:
> On Aug 11, 10:41*am, Dave Nadler > wrote:
>
>
>
> > On Aug 11, 11:27*am, Westbender > wrote:
>
> > > On Aug 11, 10:09*am, mattm > wrote:
>
> > > > On Aug 11, 10:41*am, Westbender > wrote:
>
> > > > > Forgive me if this is a really dumb question. I don't know much about
> > > > > transponder operation.
>
> > > > > Is it a technical requirement for a transponder to only transmit when
> > > > > it's been interrogated by a ping from a remote source? I'm just
> > > > > wondering why transponders can't have a "timeout" mechanism built into
> > > > > it where it will automatically report/transmit if it hasn't been
> > > > > pinged in a certain amount of time. Something like a 30 second
> > > > > timeout? Maybe user-selectable? For the folks who fly in remote areas,
> > > > > wouldn't something like this help? Or is the transponder response of
> > > > > no use without pairing it with a request (ping)?
>
> > > > That's the meaning of "transponder" -- it transmits a response (to a
> > > > radar paint), plus it includes additional information. *It goes back
> > > > to
> > > > WWII days when it was originally known as IFF -- Identify Friend or
> > > > Foe. *The detection methods based on transponder response depend
> > > > on the timing between when the primary pulse is seen and the response.
> > > > The larger the duration, the further from the transponder you are.
>
> > > > This is the point of the FLARM scheme -- all the units periodically
> > > > broadcast their status, so they are visible even when there is no
> > > > radar around.
>
> > > > -- Matt
>
> > > When I read the "how it works" on the Zaon website, it says it reads
> > > the response. It doesn't say anything about using the primary pulse in
> > > it's process. Is that typical of PCAS systems?
>
> > > This is where my question originates. It seems that the PCAS system
> > > might not need the initial request from a radar to evaluate threats.
> > > If so, then wouldn't an aircraft transponder "replying" without a
> > > radar pulse give surrounding aircraft with PCAS the means to detect?
>
> > A PCAS system replies on someone else interrogating the
> > transponders. "Someone" is either a ground radar station or
> > a TCAS-II equipped aircraft. If you are in a valley without
> > radar and without overflying jets, you will hear nothing.
>
> > Hope that helps,
> > Best Regards, Dave- Hide quoted text -
>
> > - Show quoted text -
>
> Right, did you read my first post?
>
> Since the MRX PCAS (passive) only uses the reply from transponders,
> wouldn't it be nice if the trig had a timed/scheduled transmit when
> not interrogated for a certain amount of time? If so, a combination of
> a trig/PCAS would be relatively inexpensive for glider-to-glider
> detection (yeah, yeah, assuming everyone had that combo). The best
> part would be the benefits of the "normal" operating mode of the trig
> and PCAS in relation to other GA and commercial aircraft.
>
> What are the ramifications of doing something such a thing?

I am not sure you want a bunch of transponders flying around sending
out what look like false replies to interrogations. And nobody is
going to be interested in trying to do this, there is no RTCA standard
for transponders to comply with that would allow this and nobody is
going to be interested in looking at this given the move to ADS-B.

The evolution of this thought process leads directly to ADS-B 1090ES
which is the automatic transmission of the aircraft position and other
data from the transponder without interrogation. Those transmissions
are clearly distinguishable from a conventional transponder
interrogation reply. A traditional PCAS unit will not decode the
threat altitude from that transmission and therefore not alert on the
threat.

Darryl

Westbender

August 11th 10, 05:44 PM

Thanks!

Just an attempt to think outside the box a little. I figured there had
to be a good reason it couldn't work. It's just too simple a
solution... :o)

brianDG303[_2_]

August 11th 10, 05:55 PM

On Aug 11, 9:44*am, Westbender > wrote:
> Thanks!
>
> Just an attempt to think outside the box a little. I figured there had
> to be a good reason it couldn't work. It's just too simple a
> solution... *:o)

This is a question, not a proposal. Would pushing the IDENT button on
the transponder allow you to be seen by PCAS? I am really not
suggesting that we push the IDENT button every 20 seconds but I am
curious.

Darryl Ramm

August 11th 10, 06:04 PM

On Aug 11, 9:55*am, brianDG303 > wrote:
> On Aug 11, 9:44*am, Westbender > wrote:
>
> > Thanks!
>
> > Just an attempt to think outside the box a little. I figured there had
> > to be a good reason it couldn't work. It's just too simple a
> > solution... *:o)
>
> This is a question, not a proposal. Would pushing the IDENT button on
> the transponder allow you to be seen by PCAS? I am really not
> suggesting that we push the IDENT button every 20 seconds but I am
> curious.

Nope. Pushing the ident buttons just changes slightly the reply the
transponder sends to some of the interrogations it receives. I adds
the "SPI" pulse at the end of all Mode A interrogation for ~19 seconds
after you push the ident button.

Do not go pushing that button without being told to by ATC (I've even
seen folklore where people thought you were supposed to always press
ident after changing transponder code). You may annoy your friendly
ATC guy.

Darryl

Sven[_2_]

August 11th 10, 06:15 PM

I fly in Worcester South Africa, and most of our fleet has been flarm
equipped soon after flarm came onto the market. Prior to that i lost
two very good friends (both very competent and experienced pilots) in
a mid-air. We have also had a number of mid-airs over the years in SA.
In Worcester we do some ridge flying and it really makes sense to use
flarm.
I have also flown with flarm in a number of international contests. My
latest experience has been Prievidza - most gliders were flarm
equipped - to the extent that one would even feel some mild iritation
if someone came close and there was no collision warning, as you
realised that glider was not flarm equipped. The algorithms are well
sorted now, and the collision warnings are for those you really need
the warning. Incidenlty the mid-air we did have on the first day was
been a non-flarm equipped glider and a flarm equipped glider. In a
sense i rest my case (I accept, of course, that it won't always help,
AND that you have to do all the things you are meant to do).
As some-one else has pointed out - flarm is a fully functional
solution for a very real problem (especially in contests).
It is also relatively inexpensive - it is also a logger and you can
run your pda from it (you can also link it to a voice system (such as
Triadis-DVS) or the butterlfy display.
Cynically i may say that i don't care whether you wear a parachute or
not, as my parachute will function irrespective of yours.
Flarm is different - it only works for me if you also have one.

John Smith

August 11th 10, 06:59 PM

Sven wrote:
> I have also flown with flarm in a number of international contests. My
> latest experience has been Prievidza - most gliders were flarm
> equipped - to the extent that one would even feel some mild iritation
> if someone came close and there was no collision warning, as you
> realised that glider was not flarm equipped.

When I was flying on one of those "glider highways" in Europe, I once
heard a radio call: Attention to all, there's a non-FLARM-equipped
glider coming!

brianDG303[_2_]

August 11th 10, 07:00 PM

Brad Hill and I ordered a PowerFlarm each and that means we have
achieved 25% penetration of the core XC group from our field.

Brian

Ramy

August 11th 10, 07:15 PM

On Aug 11, 9:23*am, Darryl Ramm > wrote:
> On Aug 11, 8:07*am, William Gagen > wrote:
>
>
>
>
>
> > FLARM - We NEED it yesterday.
>
> > How many more midairs do we need to have in our sport?
>
> > What if we have a midair with an airliner? Can you say soaring as a
> > sport is dead, as the FAA will reflexively eliminate all of our
> > flexibility.
>
> > The cost of FLARM in any form is negligible compared to staying
> > alive.
>
> > I have used FLARM at the IMGC Competition (International Military
> > Glider Comp) in Germany, and it turned a competition with 93 gliders
> > into the safest competition I have ever flown in anywhere.
>
> > It provides timely, accurate, important alerts for collision potential
> > with very few spurious or distracting warnings. It is vastly superior
> > to PCAS. There is absolutely no reason we shouldn't be requiring it
> > for all competition aircraft PERIOD!
>
> > The following midairs could all have been prevented by FLARM: Parowan
> > this summer, Uvalde this summer, Boulder last winter, the Hudson River
> > helicopter/light plane midair.
>
> > Thanks for reading my rant. But, having used it, I know how good it
> > is, and why we need it yesterday!
>
> > SSA could be helpful by providing loaner or rental FLARM units to
> > aircraft to use in competitions. In this way, we could get them into
> > every competition sooner. A pilot could rent a unit for say $100 a
> > competition, and over 2 summers the units would be paid off.
>
> There is a gamut of collision scenarios from glider-glider, glider-
> towplane, glider-GA, glider-fast-jet and glider-airliner and there is
> no single technology or single product that well addresses all these
> problems. The first thing in thinking about collision avoidance is to
> be very clear just what problem(s) you are trying to solve.
>
> I agree that Flarm and (and in the USA the flarm-flarm part of
> PowerFLARM product) can be a significant help in glide-glider and
> glider-towplane collision scenarios and I agree that the collision
> with an airliner is a horrible scenario, for the innocent passengers
> and crew, and would cause incredible damage to our sport. However
> unfortunately this post seems to jumble up too much of all this
> collision avoidance/traffic awareness technology and the capabilities
> and benefits and that worries me.
>
> The post talks about "flarm" helping with airliner collision avoidance
> and that is a dangerous claim to make without some careful
> qualification and is certainly not true with with the traditional
> flarm product in Europe. Flarm (the flarm-flarm protocol) has nothing
> to do with avoiding airliner collisions. Airliners and fast jets (and
> most GA traffic outside of say tow planes) just will not be able to
> receive or transmit the flarm protocol and the flarm protocol does not
> make a glider visible to ATC.
>
> The PowerFLARM product with 1090ES can receiver ADS-B over 1090ES.
> Most airliners, fast jets and GA aircraft are not yet equipped with
> 1090ES data out. Rule for ADS-B equipage vary between Europe and the
> USA, all airliners eventually will have 1090ES data-out but I don't
> think anybody has good timelines yet for when a significant fraction
> of them will be equipped. Once 1090ES data-out equipped a PowerFLARM
> would "see" that traffic via 1090ES. The PowerFLARM will "see"
> airliner traffic today via PCAS but obviously not get direction
> information and PCAS tends to operate at relatively short range for
> the fast closure rates involved in a collison with an airliner or fast-
> jet. In general it really is a bad idea to think gliders are going to
> operate in areas of high-density airline or fast-jet traffic and rely
> on PCAS or ADS-B receivers to help provide avoid mid-air collisions.
> The closure rates are high, gliders are often invisible to ATC primary
> radar, and gliders are incredibly hard to see for those flight crews
> even if they are aware/expecting the glider traffic.
>
> In the USA and Europe effectively all airliners, many fast-jets and
> many military transpots etc. are TCAS equipped, and many of that is
> TCAS II. TCAS II provides those flight crew with mandatory climb/
> descent instruction to avoid collisions. These instructions must be
> followed and override ATC instructions to the pilot. Flarm and
> PowerFLARM do not provide any visibility to TCAS and a TCAS equipped
> airliner or fast jet will plow right through a glider equipped with
> Flarm or PowerFLARM with no warning. *A Mode C or Mode S transponder
> is the only device that both provide visibility to ATC radar and to
> TCAS systems (and also TAS/TCAD and PCAS systems).
>
> For all these reasons it is important for areas of high density
> airline and fast-jet traffic that glider pilots continue to consider
> equipping with transponders. It will will be concerning in those area
> if say PowerFLARM is seen by some pilots as simple alternative to
> transponder adaption.
>
> The post also compares PCAS to Flarm. Many pilots in the USA use PCAS
> for awareness of GA traffic and that is not addressed by traditional
> Flarm units. The PowerFLARM is interesting in it does includes PCAS
> capabilities.
>
> The PCAS and 1090ES receiver capability of the PowerFLARM make it very
> interesting to combine with a Mode S transponder with 1090ES data out
> capability (like the Trig TT21) and that provides a solution that does
> address a wide range of collision scenario. But in the USA even that
> system will have issues at times inter-operating with UAT systems in
> the dual-line ADS-B system in the USA (e.g. the issues with operating
> outside of GBT coverage that I've described before in this thread).
>
> ---
>
> I would also be careful claiming Flarm would prevent specific
> accidents without a careful analysis. Especially because it is
> unlikely that many GA aircraft will equip with a Flarm or PowerFLARM
> device. So I'm not sure I claim absolutely that this would prevent the
> Colorado mid-air with a Cirrus. PowerFLARM in the glider and tow plane
> may have detected the Cirrus via PCAS, the Cirrus transponder may have
> been interrogated enough to provide a PCAS alert but you have issues
> of PCAS accuracy and false alarms especially if either or both the tow-
> plane or glider have transponders. And I am not aware of what if any
> traffic awareness system the Cirrus had on board. I not sure Flarm or
> PowerFLARM are really relevant to the Hudson river collision, as those
> aircraft are just not likely to equip with either product. It is more
> likely in future that those aircraft would equip with GA oriented PCAS
> or ADS-B data-out and data-in products, if they were both suitably
> equipped in future then yes, hopefully that would reduce the chance
> for such a collision. PCAS itself may be problematic is some areas
> like this because of the high traffic density and high alarm rates.
>
> Darryl- Hide quoted text -
>
> - Show quoted text -

One thing to note for those already using a PCAS is that the
PowerFlarm can replace your PCAS unit, so you can save few hundred
bucks by selling your PCAS unit on Ebay. I am curious to know how the
PowerFlarm performs as a PCAS vs the ZAON MRX. While the MRX
definitely detects more aircrafts than our eyes, I often find the
audio alert does not give early enough warnings. Was any comparison
done between the units?

While I believe almost all of us (except maybe Mike) are sold on the
PowerFlarm, and I am definitely going to buy one, it will be good to
show some statistics of how effective the Flarm was so far in reducing
mid airs, in particular, if any midair occured between 2 gliders
equipped with operaional flarms.

Assuming the PowerFlarm will be available really soon (anyone knows
when?), and based on the feedbacks we heard so far from pilots using
it in contests, I can hardly imagine that anyone will want to fly in
a contest again without one after the chain of midairs we had
recently. I hope it will be mandatory, but to make it mandatory no
doubt the SSA should be able to rent them first, at least for the
first year or so, as I am sure everyone will want to buy one after
renting it once. At this rate I expect with some peer pressure most
pilots will be equiped with Flarms soon, those who don't will have
hard time sharing the sky with their buddies.

And last, I am not sure why the claim that GA pilots are not going to
adopt the PowerFlarm. They also suffer from midairs, and most of them
can efford it as well. I believe the ZAON MRX is quiet popular among
GA pilots as well, so I would expect the same to be true with
PowerFlarm which can replace the MRX and cost only $1K or so more.

Ramy

Andrzej Kobus

August 11th 10, 07:28 PM

Let's take a real life example. Last year I flew in Sports Nationals
in Elmira. I had PCAS with me. The first day after I released and
started climbing with a bunch of other gliders many of them equipped
with transponders I had to switch my PCAS off because of the quantity
of warnings. It was useless in that scenario.

Now, isn't a PowerFlarm unit a FLARM and PCAS in one box? Can I switch
off PCAS while leaving FLARM on when I am in a thermal with a bunch of
transponder equipped gliders so I don't get overwhelmed by warnings.
Once on task I could turn PCAS back on but in a congested thermal I
may not want to see it on.

Anyone knows how this situation would be handled by PowerFlarm?

Darryl Ramm

August 11th 10, 07:42 PM

On Aug 11, 11:15*am, Ramy > wrote:
> On Aug 11, 9:23*am, Darryl Ramm > wrote:
>
>
>
> > On Aug 11, 8:07*am, William Gagen > wrote:
>
> > > FLARM - We NEED it yesterday.
>
> > > How many more midairs do we need to have in our sport?
>
> > > What if we have a midair with an airliner? Can you say soaring as a
> > > sport is dead, as the FAA will reflexively eliminate all of our
> > > flexibility.
>
> > > The cost of FLARM in any form is negligible compared to staying
> > > alive.
>
> > > I have used FLARM at the IMGC Competition (International Military
> > > Glider Comp) in Germany, and it turned a competition with 93 gliders
> > > into the safest competition I have ever flown in anywhere.
>
> > > It provides timely, accurate, important alerts for collision potential
> > > with very few spurious or distracting warnings. It is vastly superior
> > > to PCAS. There is absolutely no reason we shouldn't be requiring it
> > > for all competition aircraft PERIOD!
>
> > > The following midairs could all have been prevented by FLARM: Parowan
> > > this summer, Uvalde this summer, Boulder last winter, the Hudson River
> > > helicopter/light plane midair.
>
> > > Thanks for reading my rant. But, having used it, I know how good it
> > > is, and why we need it yesterday!
>
> > > SSA could be helpful by providing loaner or rental FLARM units to
> > > aircraft to use in competitions. In this way, we could get them into
> > > every competition sooner. A pilot could rent a unit for say $100 a
> > > competition, and over 2 summers the units would be paid off.
>
> > There is a gamut of collision scenarios from glider-glider, glider-
> > towplane, glider-GA, glider-fast-jet and glider-airliner and there is
> > no single technology or single product that well addresses all these
> > problems. The first thing in thinking about collision avoidance is to
> > be very clear just what problem(s) you are trying to solve.
>
> > I agree that Flarm and (and in the USA the flarm-flarm part of
> > PowerFLARM product) can be a significant help in glide-glider and
> > glider-towplane collision scenarios and I agree that the collision
> > with an airliner is a horrible scenario, for the innocent passengers
> > and crew, and would cause incredible damage to our sport. However
> > unfortunately this post seems to jumble up too much of all this
> > collision avoidance/traffic awareness technology and the capabilities
> > and benefits and that worries me.
>
> > The post talks about "flarm" helping with airliner collision avoidance
> > and that is a dangerous claim to make without some careful
> > qualification and is certainly not true with with the traditional
> > flarm product in Europe. Flarm (the flarm-flarm protocol) has nothing
> > to do with avoiding airliner collisions. Airliners and fast jets (and
> > most GA traffic outside of say tow planes) just will not be able to
> > receive or transmit the flarm protocol and the flarm protocol does not
> > make a glider visible to ATC.
>
> > The PowerFLARM product with 1090ES can receiver ADS-B over 1090ES.
> > Most airliners, fast jets and GA aircraft are not yet equipped with
> > 1090ES data out. Rule for ADS-B equipage vary between Europe and the
> > USA, all airliners eventually will have 1090ES data-out but I don't
> > think anybody has good timelines yet for when a significant fraction
> > of them will be equipped. Once 1090ES data-out equipped a PowerFLARM
> > would "see" that traffic via 1090ES. The PowerFLARM will "see"
> > airliner traffic today via PCAS but obviously not get direction
> > information and PCAS tends to operate at relatively short range for
> > the fast closure rates involved in a collison with an airliner or fast-
> > jet. In general it really is a bad idea to think gliders are going to
> > operate in areas of high-density airline or fast-jet traffic and rely
> > on PCAS or ADS-B receivers to help provide avoid mid-air collisions.
> > The closure rates are high, gliders are often invisible to ATC primary
> > radar, and gliders are incredibly hard to see for those flight crews
> > even if they are aware/expecting the glider traffic.
>
> > In the USA and Europe effectively all airliners, many fast-jets and
> > many military transpots etc. are TCAS equipped, and many of that is
> > TCAS II. TCAS II provides those flight crew with mandatory climb/
> > descent instruction to avoid collisions. These instructions must be
> > followed and override ATC instructions to the pilot. Flarm and
> > PowerFLARM do not provide any visibility to TCAS and a TCAS equipped
> > airliner or fast jet will plow right through a glider equipped with
> > Flarm or PowerFLARM with no warning. *A Mode C or Mode S transponder
> > is the only device that both provide visibility to ATC radar and to
> > TCAS systems (and also TAS/TCAD and PCAS systems).
>
> > For all these reasons it is important for areas of high density
> > airline and fast-jet traffic that glider pilots continue to consider
> > equipping with transponders. It will will be concerning in those area
> > if say PowerFLARM is seen by some pilots as simple alternative to
> > transponder adaption.
>
> > The post also compares PCAS to Flarm. Many pilots in the USA use PCAS
> > for awareness of GA traffic and that is not addressed by traditional
> > Flarm units. The PowerFLARM is interesting in it does includes PCAS
> > capabilities.
>
> > The PCAS and 1090ES receiver capability of the PowerFLARM make it very
> > interesting to combine with a Mode S transponder with 1090ES data out
> > capability (like the Trig TT21) and that provides a solution that does
> > address a wide range of collision scenario. But in the USA even that
> > system will have issues at times inter-operating with UAT systems in
> > the dual-line ADS-B system in the USA (e.g. the issues with operating
> > outside of GBT coverage that I've described before in this thread).
>
> > ---
>
> > I would also be careful claiming Flarm would prevent specific
> > accidents without a careful analysis. Especially because it is
> > unlikely that many GA aircraft will equip with a Flarm or PowerFLARM
> > device. So I'm not sure I claim absolutely that this would prevent the
> > Colorado mid-air with a Cirrus. PowerFLARM in the glider and tow plane
> > may have detected the Cirrus via PCAS, the Cirrus transponder may have
> > been interrogated enough to provide a PCAS alert but you have issues
> > of PCAS accuracy and false alarms especially if either or both the tow-
> > plane or glider have transponders. And I am not aware of what if any
> > traffic awareness system the Cirrus had on board. I not sure Flarm or
> > PowerFLARM are really relevant to the Hudson river collision, as those
> > aircraft are just not likely to equip with either product. It is more
> > likely in future that those aircraft would equip with GA oriented PCAS
> > or ADS-B data-out and data-in products, if they were both suitably
> > equipped in future then yes, hopefully that would reduce the chance
> > for such a collision. PCAS itself may be problematic is some areas
> > like this because of the high traffic density and high alarm rates.
>
> > Darryl- Hide quoted text -
>
> > - Show quoted text -
>
> One thing to note for those already using a PCAS is that the
> PowerFlarm can replace your PCAS unit, so you can save few hundred
> bucks by selling your PCAS unit on Ebay. I am curious to know how the
> PowerFlarm performs as a PCAS vs the ZAON MRX. While the MRX
> definitely detects more aircrafts than our eyes, I often find the
> audio alert does not give early enough warnings. Was any comparison
> done between the units?
>
> While I believe almost all of us (except maybe Mike) are sold on the
> PowerFlarm, and I am definitely going to buy one, *it will be good to
> show some statistics of how effective the Flarm was so far in reducing
> mid airs, in particular, if any midair occured between 2 gliders
> equipped with operaional flarms.
>
> Assuming the PowerFlarm will be available really soon (anyone knows
> when?), and based on the feedbacks we heard so far from pilots using
> it in contests, *I can hardly imagine that anyone will want to fly in
> a contest again without one after the chain of midairs we had
> recently. I hope it will be mandatory, but to make it mandatory no
> doubt the SSA should be able to rent them first, at least for the
> first year or so, as I am sure everyone will want to buy one after
> renting it once. At this rate I expect with some peer pressure most
> pilots will be equiped with Flarms soon, those who don't will have
> hard time sharing the sky with their buddies.
>
> And last, I am not sure why the claim that GA pilots are not going to
> adopt the PowerFlarm. They also suffer from midairs, and most of them
> can efford it as well. I believe the ZAON MRX is quiet popular among
> GA pilots as well, so I would expect the same to be true with
> PowerFlarm which can replace the MRX and cost only $1K or so more.
>
> Ramy

I do worry that the SSA does not bog down worrying about things like
renting units. The most important thing to do is make a clean decision
asap and let affected people know. I do not think there is a need to
prove the underlying FLARM technology works and you just need to look
here for pilots willing to open their wallets and start the ball
rolling. By all means allow others to rent out or loan systems, and I
am confident that will happen given a clean decision requiring devices
in contests. I worry it is easy to over complicate some of these
decisons that should really be driven by a safety/risk analysis as
long as the cost is reasonable and it looks at least to me like it
is.

The broader GA community will not adopt PowerFLARM for the flap
protocol - most of them won't worry about other flarm traffic. Pilots
wanting an ADS-B receiver might adopt the PowerFLARM but I suspect
many more will adopt devices more tailored for the GA cockpit, like in
the mid-range the recently announced Trig 1090ES receiver (e.g. it has
compatibility with popular GA fixed and portable traffic displays that
the PowerFLARM does not provide). At the low-end of the GA marked I'd
also wait and see what other products companies like Zaon bring to
market. I expect to see more ADS-B products aimed at the GA market -
but none will meet the needs that PowerFLARM does for us. While ADS-B
receivers will be interesting to GA pilots, the other pressure on GA
is going to be mandatory adoption of ADS-B transmitters and with the
pressure to spend money on that over the rest of this decade is going
to be interesting to see where pilots spend their avionics $$$.

Darryl

Westbender

August 11th 10, 07:48 PM

On Aug 11, 1:28*pm, Andrzej Kobus > wrote:
> Let's take a real life example. Last year I flew in Sports Nationals
> in Elmira. I had PCAS with me. The first day after I released and
> started climbing with a bunch of other gliders many of them equipped
> with transponders I had to switch my PCAS off because of the quantity
> of warnings. It was useless in that scenario.
>
> Now, isn't a PowerFlarm unit a FLARM and PCAS in one box? Can I switch
> off PCAS while leaving FLARM on when I am in a thermal with a bunch of
> transponder equipped gliders so I don't get overwhelmed by warnings.
> Once on task I could turn PCAS back on but in a congested thermal I
> may not want to see it on.
>
> Anyone knows how this situation would be handled by PowerFlarm?

This brings up a good question. Does the Powerflarm's collision
detection logic that is "tuned" for sailplanes apply to all input
(flarm, ads-b, mode c/s)?

If it is, no need to disable anything.

Andy[_1_]

August 11th 10, 07:51 PM

On Aug 11, 11:28*am, Andrzej Kobus > wrote:

> Anyone knows how this situation would be handled by PowerFlarm?

I hope that the PCAS function of PowerFLARM will either support target
specific alert suppression or will provide some other means of
eliminating nuissance transponder alerts. Without that it will be as
worthless as the ZAON MRX in a transponder rich glider environment.

There appears to be no public data on how the display or output data
stream will distinguish between targets detected by each supported
method. There also appears to be no public data on what alerting will
be provided for each target type. A lot seems to riding on the faith
that the other detection methods will be supported as well as the
FLARM targets.

As I said before the technical specs are very sparse and certainly not
complete enough yet for this engineer to spend $1.5k.

Andy

Darryl Ramm

August 11th 10, 08:05 PM

On Aug 11, 11:48*am, Westbender > wrote:
> On Aug 11, 1:28*pm, Andrzej Kobus > wrote:
>
> > Let's take a real life example. Last year I flew in Sports Nationals
> > in Elmira. I had PCAS with me. The first day after I released and
> > started climbing with a bunch of other gliders many of them equipped
> > with transponders I had to switch my PCAS off because of the quantity
> > of warnings. It was useless in that scenario.
>
> > Now, isn't a PowerFlarm unit a FLARM and PCAS in one box? Can I switch
> > off PCAS while leaving FLARM on when I am in a thermal with a bunch of
> > transponder equipped gliders so I don't get overwhelmed by warnings.
> > Once on task I could turn PCAS back on but in a congested thermal I
> > may not want to see it on.
>
> > Anyone knows how this situation would be handled by PowerFlarm?
>
> This brings up a good question. Does the Powerflarm's collision
> detection logic that is "tuned" for sailplanes apply to all input
> (flarm, ads-b, mode c/s)?
>
> If it is, no need to disable anything.

It can't apply to PCAS (Mode C/S) because the PowerFLARM has no idea
of the direction of the threat, only the relative altitude and a
relatively crude estimate of the distance. There is also no way to
reliably use other tricks to correlate the threat's transponder with
an on-board flarm that you could do with say an ADS-B transmitter.
PCAS units have all traditionally had settings for alert volumes to
handle flying in different environments and pilot preferences and I'd
be very surprised if the PowerFLARM was any different but I have no
specific information on that.

I agree that ButterFly/FLARM would be better served with more
technical information, FAQs etc., including some tailored for the USA,
on their web site.

Darryl

Ramy

August 11th 10, 08:15 PM

On Aug 11, 11:42*am, Darryl Ramm > wrote:

>
> I do worry that the SSA does not bog down worrying about things like
> renting units. The most important thing to do is make a clean decision
> asap and let affected people know. I do not think there is a need to
> prove the underlying FLARM technology works and you just need to look
> here for pilots willing to open their wallets and start the ball
> rolling. By all means allow others to rent out or loan systems, and I
> am confident that will happen given a clean decision requiring devices
> in contests. I worry it is easy to over complicate some of these
> decisons that should really be driven by a safety/risk analysis as
> long as the cost is reasonable and it looks at least to me like it
> is.
>
> The broader GA community will not adopt PowerFLARM for the flap
> protocol - most of them won't worry about other flarm traffic. Pilots
> wanting an ADS-B receiver might adopt the PowerFLARM but I suspect
> many more will adopt devices more tailored for the GA cockpit, like in
> the mid-range the recently announced Trig 1090ES receiver (e.g. it has
> compatibility with popular GA fixed and portable traffic displays that
> the PowerFLARM does not provide). At the low-end of the GA marked I'd
> also wait and see what other products companies like Zaon bring to
> market. I expect to see more ADS-B products aimed at the GA market -
> but none will meet the needs that PowerFLARM does for us. *While ADS-B
> receivers will be interesting to GA pilots, the other pressure on GA
> is going to be mandatory adoption of ADS-B transmitters and with the
> pressure to spend money on that over the rest of this decade is going
> to be interesting to see where pilots spend their avionics $$$.
>
> Darryl

Maybe I got lost in details, but I don't see much difference (except
the thermaling specific algorithms) between our needs and GA needs, at
least the slower "low end" GA which does not already use more
sofisticated traffic alert equipment than PCAS. If it is the best
solution for us, why isn't it for them? If they buy PCAS, why wouldn't
they buy PowerFlarm?
Also, are we making assumptions that we will be exempt from any future
GA mandatory adoptions again? It is not like we are posing less threat
than GA, on the contrary (less visible, less predictable and can be at
any altitude) and with all the recent attention we got I doubt we will
be exempt. As such, if we are willing to spend $$ on a temporary
solution which will undoubtly save some lives in the next 10 years or
so, why wouldn't GA?

Ramy

Greg Arnold

August 11th 10, 08:19 PM

On 8/11/2010 12:15 PM, Ramy wrote:

>
> Maybe I got lost in details, but I don't see much difference (except
> the thermaling specific algorithms) between our needs and GA needs, at
> least the slower "low end" GA which does not already use more
> sofisticated traffic alert equipment than PCAS. If it is the best
> solution for us, why isn't it for them? If they buy PCAS, why wouldn't
> they buy PowerFlarm?

PowerFlarm may have fancy software to try to take into account that
gliders often do not fly straight. However, PowerFlarm certainly can
handle the simpler situation where planes do fly straight, and so I
would think Ramy is right -- PowerFlarm would be very useful to GA.

Ramy

August 11th 10, 08:21 PM

On Aug 11, 11:51*am, Andy > wrote:
> On Aug 11, 11:28*am, Andrzej Kobus > wrote:
>
> > Anyone knows how this situation would be handled by PowerFlarm?
>
> I hope that the PCAS function of PowerFLARM will either support target
> specific alert suppression or will provide some other means of
> eliminating nuissance transponder alerts. *Without that it will be as
> worthless as the ZAON MRX in a transponder rich glider environment.
>
> There appears to be no public data on how the display or output data
> stream will distinguish between targets detected by each supported
> method. *There also appears to be no public data on what alerting will
> be provided for each target type. *A lot seems to riding on the faith
> that the other detection methods will be supported as well as the
> FLARM targets.
>
> As I said before the technical specs are very sparse and certainly not
> complete enough yet for this engineer to spend $1.5k.
>
> Andy

Good points. Let's hope that the PowerFlarm dudes are reading this
discussion, taking notes and will provide some answers soon.

Ramy

Westbender

August 11th 10, 08:35 PM

>
> It can't apply to PCAS (Mode C/S) because the PowerFLARM has no idea
> of the direction of the threat, only the relative altitude and a
> relatively crude estimate of the distance. There is also no way to
> reliably use other tricks to correlate the threat's transponder with
> an on-board flarm that you could do with say an ADS-B transmitter.
> PCAS units have all traditionally had settings for alert volumes to
> handle flying in different environments and pilot preferences and I'd
> be very surprised if the PowerFLARM was any different but I have no
> specific information on that.
>
> - Show quoted text -

Ok, that changes things. Thanks for clarifying that for me.

Where I fly, it's very unlikely for any fellow flyers to adopt flarm.
If it could apply the same threat logic to non-flarm inputs I would
probably go for it. I've been on the verge of buying the MRX PCAS, but
I need to see more reason to spend the extra grand. I know it's more
"future-proof" than the MRX, but when does that pay off for my
sitation. Who knows. By the time ADS-B is in full swing, there may be
more cost-effective options for sailplanes.

Maybe I could buy a Powerflarm and rent it on occasion to the contest
guys. :o)

Steve Koerner

August 11th 10, 08:37 PM

On Aug 11, 11:51*am, Andy > wrote:
> On Aug 11, 11:28*am, Andrzej Kobus > wrote:
>
> > Anyone knows how this situation would be handled by PowerFlarm?
>
> I hope that the PCAS function of PowerFLARM will either support target
> specific alert suppression or will provide some other means of
> eliminating nuissance transponder alerts. *Without that it will be as
> worthless as the ZAON MRX in a transponder rich glider environment.
>
> There appears to be no public data on how the display or output data
> stream will distinguish between targets detected by each supported
> method. *There also appears to be no public data on what alerting will
> be provided for each target type. *A lot seems to riding on the faith
> that the other detection methods will be supported as well as the
> FLARM targets.
>
> As I said before the technical specs are very sparse and certainly not
> complete enough yet for this engineer to spend $1.5k.
>
> Andy

Andy -- have some faith. The Flarm designers are glider pilots and
have been at this for years. The track record is that of remarkable
success. Even if it should happen that they screw up and don't put
separate volume functions in the initial release they are not going to
leave something stupid in the code for long. That would be a trivial
fix.

This engineer has ordered a unit!

Darryl Ramm

August 11th 10, 08:56 PM

On Aug 11, 12:19*pm, Greg Arnold > wrote:
> On 8/11/2010 12:15 PM, Ramy wrote:
>
>
>
> > Maybe I got lost in details, but I don't see much difference (except
> > the thermaling specific algorithms) between our needs and GA needs, at
> > least the slower "low end" GA which does not already use more
> > sofisticated traffic alert equipment than PCAS. If it is the best
> > solution for us, why isn't it for them? If they buy PCAS, why wouldn't
> > they buy PowerFlarm?
>
> PowerFlarm may have fancy software to try to take into account that
> gliders often do not fly straight. *However, PowerFlarm certainly can
> handle the simpler situation where planes do fly straight, and so I
> would think Ramy is right -- PowerFlarm would be very useful to GA.

A couple of points, some restated..

The PowerFLARM does no support popular portable or fixed dispays used
in the GA market. That may be an issue for some pilots. That is also
something FLARM could address in future (with software and/or hardware
changes).

To have the flarm protocol be useful you have to have significant
adoption. And I just do not see why or how that would happen in the GA
market. I could see examples offered before of pockets of possible
interest (news/rescue helicopters, fire bombers/spotters, logging
helicopters).

To have the ADS-B part work you need an ADS-B transmitter. For the low-
end part of the GA market in the USA most likely to adopt ADS-B data-
out (voluntarily or to meet mandate requirements) typically have Mode
C transponders today. For those lower-end aircraft I expect UAT
devices as presumably they appear (and gain TSO approval) to be
appealing. It is not clear there will be a separate UAT transmitter
market. I expect to see transceivers and receivers.

For more modern aircraft with Mode S transponders I expect is more
likely for pilots to upgrade their Mode S to 1090ES data out and at
the low-end of that group the PowerFLARM as an add-on receiver could
be interesting if the issue of display compatibility does not matter.
But in that market of more modern GA aircraft you rapidly run into
cockpits where owners/pilots are more likely to want to deploy
something that integrates with their current display and other toys
even if not IFR certified. More complex cockpits also raise some
interesting questions of device compatibility (ability to correctly
set the capability code bits for ADS-B) that seem to be an open
question and it is not clear that all these GA modern glass panel
systems will necessarily be compatible with portable ADS-B receivers
(this is mostly a USA issue). ADS-B is a slow painful process so we
need to really see what happens. If a PowerFLARM was priced close to
an Zaon MRX then I'd say its a no-brainer for any low-end GA pilot to
adopt it. The PCAS feature in the PowerFLARM is a nice feature that
other 1090ES receivers are not providing but I'm sure that will sway
much of the GA market, esp. compared to display compatibility etc.

The USA market, with its dual-link and UAT options is a bit different
than Europe. Europe has mandatory Mode S transponders and is going
1090ES data-out only. And I expect the PowerFLARM to be relatively
more appealing to lower-end GA pilots there than in the USA. I am not
saying a GA pilot cannot or should not use a PowerFLARM I am trying to
point out that as the product looks today it may be a significantly
less compelling product in the USA GA market than some glider pilots
seem to be assuming. If Flarm/Butterfly want to target the USA GA
market there are some obvious things they could do in future. It is a
however a very compelling product for many of us now...

Darryl

Westbender

August 11th 10, 08:57 PM

What do you guys suspect the threat display would look like on the
Powerflarm for a non-flarm threat? A ring all the way around to show
range and an altitude differential? As opposed to the small triangles
showing location, direction and altitude differential?

Just curious. Anyone know?

Andy[_1_]

August 11th 10, 09:32 PM

On Aug 11, 12:05*pm, Darryl Ramm > wrote:

> It can't apply to PCAS (Mode C/S) because the PowerFLARM has no idea
> of the direction of the threat,

Is that somewhere in the specs and I missed it. There is no reason a
passive tranponder detection system cannot be directional. It does
require a directional antenna system though. (ref Zaon XRX).

If position was only resolved to one of 4 quadrants though the
alerting could not be as good as for FLARM targets, but it could be
much better than the ZAON MRX that many of us are used to. Maybe an 8
sector directional antenna is being dreamed of. It could also be much
better than the MRX if a specific target (such as the tug) could be
tagged as "no threat". Even better if the "no threat tag" was
automatically cleared if there was a significant change in relative
altitude or direction of the tagged target. Maybe they are aware of
the fact that gliders may use a unique squawk that distinguishes them
from VFR aircraft and will provide different threat alerting.

Until there are some hard specs and real hardware with integrated and
functional software, PowerFLARM could just be a marketeers dream.

Somebody please say you have actually seen one working and shoot me
down.

Andy

Westbender

August 11th 10, 09:52 PM

From the LX website regarding the Powerflarm. See the first paragraph
and second bullet point in the summary.

Power Flarm is designed to give precise warning of the relative
positions of ADS-B transmitting aircraft and of aircraft transmitting
Flarm information. Its Mode-C warning gives both distance (accuracy
some 100m) and relative altitude (accuracy 25ft/50ft depending on
XPDR).

It utilizes the same warning technology and motion prediction used in
FLARM. This means it calculates hazard-levels as a function of many
parameters and not only distance. (Its algorithms continually
calculate and forecast possible flight vectors and matches them to
probabilities) Warnings are given visually and acoustically depending
on the severity of the hazard.

The display and user-interface is designed to minimize distraction.

In summary it detects:

•other ADS-B equipped aircraft without PowerFLARM
•other Mode-C/S XPDR equipped aircraft ( range but not direction)
•other aircraft with normal FLARM compatible systems

And all the time it transmits its own Flarm data making you
conspicuous to other Flarm equipped aircraft

Westbender

August 11th 10, 09:58 PM

I would think it can still calculate whether a target is converging or
not (range/altitude differential). Wouldn't it need multiple xpndr
replies identifying the same target? I would guess such a thing would
be pretty difficult in a gaggle though.

I have sent an email inquiring about just how the different sources
are dealt with in terms of predicting threats. Hopefully they'll
respond.

Darryl Ramm

August 11th 10, 10:12 PM

On Aug 11, 1:32*pm, Andy > wrote:
> On Aug 11, 12:05*pm, Darryl Ramm > wrote:
>
> > It can't apply to PCAS (Mode C/S) because the PowerFLARM has no idea
> > of the direction of the threat,
>
> Is that somewhere in the specs and I missed it. *There is no reason a
> passive tranponder detection system cannot be directional. *It does
> require a directional antenna system though. (ref *Zaon XRX).
>
> If position was only resolved to one of 4 quadrants though the
> alerting could not be as good as for FLARM targets, but it could be
> much better than the ZAON MRX that many of us are used to. *Maybe an 8
> sector directional antenna is being dreamed of. *It could also be much
> better than the MRX if a specific target (such as the tug) could be
> tagged as "no threat". *Even better if the "no threat tag" was
> automatically cleared if there was a significant change in relative
> altitude or direction of the tagged target. Maybe they are aware of
> the fact that gliders may use a unique squawk that distinguishes them
> from VFR aircraft and will provide different threat alerting.
>
> Until there are some hard specs and real hardware with integrated and
> functional software, PowerFLARM could just be a marketeers dream.
>
> Somebody please say you have actually seen one working and shoot me
> down.
>
> Andy

The PowerFLARM definitely does not have a directional 1090MHz
antenna.

Chasing directional PCAS type things like the XRX is likely a waste of
time given ADS-B's arrival. I don't expect to see any other of these
directional PCAS systems from any vendors.

Darryl

Darryl Ramm

August 11th 10, 10:51 PM

On Aug 11, 1:58*pm, Westbender > wrote:
> I would think it can still calculate whether a target is converging or
> not (range/altitude differential). Wouldn't it need multiple xpndr
> replies identifying the same target? I would guess such a thing would
> be pretty difficult in a gaggle though.
>
> I have sent an email inquiring about just how the different sources
> are dealt with in terms of predicting threats. Hopefully they'll
> respond.

Those of us who fly say with a Zaon MRX seem to be pretty impressed
with its ability to give you a heads up of traffic but PCAS is
inherently so imprecise that to talk about it in the same sentence as
the high precision FLARM protocol is kind of a stretch. But I think
the idea of including PCAS in the PowerFLARM is very good.

In a crowded gaggle of gliders equipped with Mode C transponders your
PCAS unit will likely just not work in a useful way. There will be
substantial overlap of replies from transponders in the Gaggle, an
effect called syncronous garbling. If the gliders in the Gaggle have
Mode S transponders and are being interrogated by a Mode S
interrogator (like most radar and TCAS units) this effect will be
greatly minimized. Good receivers can handle some partial overlap but
a crowded gaggle of Mode C transponders is going to throw your PCAS
for a real loop. It is this sort of reason that I know PCAS cannot
reliably work and why I expect the PowerFLARM to have a way to just
turn down the PCAS alert. Its just such an obvious thing, and given
how smart the Flarm guys seem to be not something I am worried about.

In many remote areas (like where many glider contests are held?) the
interrogation rates may be low (typical SSR radar interrogate in a
burst ever 5 or 12 second rotation). You may get more rapid
interrogations for overflying aircraft TCAS etc.

All it might take for a threat aircraft is a slight change in relative
antenna orientation and the threat may appear closer. Think of two
gliders thermalling in different thermals near each other--with the
received power of their transponder signals jumping all over the
place. This is just not a foundation on which you can do much more
than beep when another threat appears to be with several miles and
some altitude window. The transmitted encoder altitude is really the
only thing you know reliably, and even that can have issues with Mode
A and Mode C signal aliasing (I'm surprised most PCAS units work as
well as they do).

Alright now I'm really beyond fed up listening to myself.

Darryl

Westbender

August 11th 10, 11:16 PM

On Aug 11, 4:51*pm, Darryl Ramm > wrote:
> On Aug 11, 1:58*pm, Westbender > wrote:
>
> > I would think it can still calculate whether a target is converging or
> > not (range/altitude differential). Wouldn't it need multiple xpndr
> > replies identifying the same target? I would guess such a thing would
> > be pretty difficult in a gaggle though.
>
> > I have sent an email inquiring about just how the different sources
> > are dealt with in terms of predicting threats. Hopefully they'll
> > respond.
>
> Those of us who fly say with a Zaon MRX seem to be pretty impressed
> with its ability to give you a heads up of traffic but PCAS is
> inherently so imprecise that to talk about it in the same sentence as
> the high precision FLARM protocol is kind of a stretch. But I think
> the idea of including PCAS in the PowerFLARM is very good.
>
> In a crowded gaggle of gliders equipped with Mode C transponders your
> PCAS unit will likely just not work in a useful way. There will be
> substantial overlap of replies from transponders in the Gaggle, an
> effect called syncronous garbling. If the gliders in the Gaggle have
> Mode S transponders and are being interrogated by a Mode S
> interrogator (like most radar and TCAS units) this effect will be
> greatly minimized. Good receivers can handle some partial overlap but
> a crowded gaggle of Mode C transponders is going to throw your PCAS
> for a real loop. It is this sort of reason that I know PCAS cannot
> reliably work and why I expect the PowerFLARM to have a way to just
> turn down the PCAS alert. Its just such an obvious thing, and given
> how smart the Flarm guys seem to be not something I am worried about.
>
> In many remote areas (like where many glider contests are held?) the
> interrogation rates may be low (typical SSR radar interrogate in a
> burst ever 5 or 12 second rotation). You may get more rapid
> interrogations for overflying aircraft TCAS etc.
>
> All it might take for a threat aircraft is a slight change in relative
> antenna orientation and the threat may appear closer. Think of two
> gliders thermalling in different thermals near each other--with the
> received power of their transponder signals jumping all over the
> place. This is just not a foundation on which you can do much more
> than beep when another threat appears to be with several miles and
> some altitude window. The transmitted encoder altitude is really the
> only thing you know reliably, and even that can have issues with Mode
> A and Mode C signal aliasing (I'm surprised most PCAS units work as
> well as they do).
>
> Alright now I'm really beyond fed up listening to myself.
>
> Darryl

Thanks Darryl, I really appreciate the info.

Eric Greenwell

August 12th 10, 04:59 AM

On 8/11/2010 12:19 PM, Greg Arnold wrote:
> On 8/11/2010 12:15 PM, Ramy wrote:
>
>>
>> Maybe I got lost in details, but I don't see much difference (except
>> the thermaling specific algorithms) between our needs and GA needs, at
>> least the slower "low end" GA which does not already use more
>> sofisticated traffic alert equipment than PCAS. If it is the best
>> solution for us, why isn't it for them? If they buy PCAS, why wouldn't
>> they buy PowerFlarm?
>
>
> PowerFlarm may have fancy software to try to take into account that
> gliders often do not fly straight. However, PowerFlarm certainly can
> handle the simpler situation where planes do fly straight, and so I
> would think Ramy is right -- PowerFlarm would be very useful to GA.
Do we have any idea of the percentage of GA using a PCAS like the MRX?
I'm of the impression it's a small percentage, smaller than the
percentage of gliders equipped with PCAS. I suspect a lot of power
pilots think they have the collision situation covered with their
transponder and Flight Following. A few that fly where there are a lot
of gliders, like the Reno area, might be interested in a Flarm unit.

--
Eric Greenwell - Washington State, USA (netto to net to email me)

- "Transponders in Sailplanes - Feb/2010" also ADS-B, PCAS, Flarm http://tinyurl.com/yb3xywl

- "A Guide to Self-launching Sailplane Operation Mar/2004" Much of what you need to know tinyurl.com/yfs7tnz

Eric Greenwell

August 12th 10, 05:21 AM

On 8/11/2010 11:28 AM, Andrzej Kobus wrote:
> Let's take a real life example. Last year I flew in Sports Nationals
> in Elmira. I had PCAS with me. The first day after I released and
> started climbing with a bunch of other gliders many of them equipped
> with transponders I had to switch my PCAS off because of the quantity
> of warnings. It was useless in that scenario.
>
Did you turn off the power, or just press the "mute" button? I've muted
mine when circling with another transponder-equipped glider so the audio
didn't annoy me, but the display continued to show the altitude
difference. That seemed useful to me.

--
Eric Greenwell - Washington State, USA (netto to net to email me)

- "Transponders in Sailplanes - Feb/2010" also ADS-B, PCAS, Flarm http://tinyurl.com/yb3xywl

- "A Guide to Self-launching Sailplane Operation Mar/2004" Much of what you need to know tinyurl.com/yfs7tnz

Eric Greenwell

August 12th 10, 06:03 AM

On 8/10/2010 9:58 PM, Alan wrote:
> A reasonable point. There is a lot of little used space to fly in.
> As someone who started as a power pilot, I still find it hard to imagine
> how one would be willing to fly in such close proximity to other aircraft
> that you cannot continuously see.
>
> "Cessna 123, traffic at your 3 o'clock, one mile, same direction" gets
> my attention.
>
> "glider 45, traffic at your 6 to 7 o'clock, 50 yards behind, 100 feet
> above, circling in same direction" sounds terrifying. (I am in a blind
> spot for him, and he is in one for me.)
>
> I worry enough about a plane a mile away in a traffic pattern. Not having
> continuous visual separation at 50 yards distance scares me.
>

Your concern is understandable, given your background, but the lack of a
motor makes circling together more predictable than attempting the same
thing with powered aircraft. Glider sink rates aren't very different
when circling, even between a high performance glider and a club
trainer, maybe 50 feet/minute. So, for each circle completed, the
altitude difference has changed only 25 feet (typical circles take 20 to
35 seconds). Also, because they are going around the circle at about the
same rate, the horizontal distance also changes slowly.

That's what makes it work: the changes in relative position are slow,
because the horizontal distances and vertical distances are changing
slowly. Another factor is visibility out of a glider cockpit: it's large
bubble canopy makes it far easier to see the other gliders than the
typical airplane cockpit allows. A very important factor is most glider
pilots have training and experience in circling together, often starting
before they have even soloed, which is not the case for airplane pilots.

Still, it is riskier than flying alone, but I don't mind doing it with
pilots I know and trust (which is most of them), and I sometimes leave
the gaggle when proper separation is too hard to maintain.
> I don't think the proprietary flarm system is the answer (being a fan of
> open standards).

Where's the problem? It works well, it's available relatively cheaply,
it's been available for years overseas, there are several licensed
manufacturers, and now it's coming the USA. I'd say the proprietary
nature is what makes all these things possible, as it guarantees all the
units will work with each other.
> I would much prefer spending my time where the only other
> traffic is likely to be a bird, and enjoying the view.
>
I enjoy that very much, but it is also great fun to sometimes fly with
other pilots. And, a good way to learn more about soaring well, too.

--
Eric Greenwell - Washington State, USA (netto to net to email me)

- "Transponders in Sailplanes - Feb/2010" also ADS-B, PCAS, Flarm http://tinyurl.com/yb3xywl

- "A Guide to Self-launching Sailplane Operation Mar/2004" Much of what you need to know tinyurl.com/yfs7tnz

Martin Gregorie[_5_]

August 12th 10, 01:33 PM

On Wed, 11 Aug 2010 04:58:03 +0000, Alan wrote:

> "glider 45, traffic at your 6 to 7 o'clock, 50 yards behind, 100 feet
> above, circling in same direction" sounds terrifying. (I am in a blind
> spot for him, and he is in one for me.)
>
> I worry enough about a plane a mile away in a traffic pattern. Not
> having
> continuous visual separation at 50 yards distance scares me.
>
Me too.

In my UK club we're trained to stay on the opposite side of the circle to
a glider at a similar height. I don't do that to anybody. If I'm in a
thermal with somebody who insists on sitting on my tail, typically a
newly solo pilot, despite my best efforts to stay opposite him, I leave.

I can't see FLARM having any bearing on this situation.

If your club instructors don't teach correct thermalling etiquette and/or
chew more experienced offenders who should know better, its time they
start doing it.

Martin

--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |

Martin Gregorie[_5_]

August 12th 10, 01:42 PM

On Thu, 12 Aug 2010 12:33:04 +0000, Martin Gregorie wrote:

> In my UK club we're trained to stay on the opposite side of the circle
> to a glider at a similar height. I don't do that to anybody. If I'm in a
> thermal with somebody who insists on sitting on my tail, typically a
> newly solo pilot, despite my best efforts to stay opposite him, I leave.
>
That should, of course, read:

"In my UK club we're trained to stay on the opposite side of the
circle to a glider at a similar height. I consciously try to do
that at all times, including when joining. If I'm in a thermal
with somebody who insists on sitting on my tail despite my best
efforts to stay opposite him, I leave."

--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |

Cats

August 12th 10, 02:03 PM

On Aug 12, 5:21*am, Eric Greenwell > wrote:
<snip>
>
> Did you turn off the power, or just press the "mute" button?
<snip>

I hope he pressed the mute button. If he turns the power off them it
has to relocate the satellites and so on when he turns it back on
again. If I turn the power off to mine I get a break in my IGC trace.

Andy[_1_]

August 12th 10, 02:30 PM

On Aug 12, 6:03*am, Cats > wrote:

> I hope he pressed the mute button. *If he turns the power off them it
> has to relocate the satellites and so on when he turns it back on
> again. *If I turn the power off to mine I get a break in my IGC trace.

I think you must be talking about FLARM but the mute/off discussion
related to ZAON PCAS.

I hit mute on mine (ZAON MRX) in the situation described and the
display does still have some value but not a lot. I generally only
look at the display after an audio alert. There is enough to look at
outside in a busy thermal.

This is why target specific muting is so important if PowerFLARM is to
be any better than the MRX for transponder based alerting. As I have
posted previously, ZAON responded that they do not have enough
processor power to implement this feature in the MRX.

Andy

Dave Hoppe

August 12th 10, 08:17 PM

On Aug 11, 3:58*pm, Westbender > wrote:
> I would think it can still calculate whether a target is converging or
> not (range/altitude differential). Wouldn't it need multiple xpndr
> replies identifying the same target? I would guess such a thing would
> be pretty difficult in a gaggle though.
>
> I have sent an email inquiring about just how the different sources
> are dealt with in terms of predicting threats. Hopefully they'll
> respond.

Here is their response to my email:

Hi Dave,

thanks for your message.

1) yes. Motion predictions are made of all data.

2) We do show relative positions of ADS-B 1090 traffic, however no
directions
are given for Mode-C/S traffic. Warnings are displayed as a ring, see
the
attached picture.

I hope my answers help, if you have any questions left please tell
me.

Kind regards
Marc
Butterfly Support

Dave Hoppe

August 12th 10, 10:40 PM

....and a followup:

Hello Dave,

yes, on the warning side there will be an option to disable all alarms
or alarms
from a specific source for a specified timeframe. This will be
accomplished
through double-clicking the rotary knob - very easy to do in-flight.

One further info: Mode-C/S warnings are only given if there is
specific threat.
Mode-C/S targets will not clutter up the radar screen.

Kind regards
Marc

Dave Hoppe

August 12th 10, 10:48 PM

I'm waiting for one more response regarding flarm frequency and
approval status in the US.

Chip Bearden[_2_]

August 12th 10, 11:11 PM

> It may make sense for contest gliders, and those operating in high
> glider traffic areas (Whites, Ridges) to get Flarm, recreational
> gliders operating in low glider but high power traffic airspace to get
> transponders and Pcas, and lucky guys out in the middle of nowhere
> to simply open eyeballs.
>
> John Cochrane

John raises an issue that surfaced at a PowerFLARM presentation Dave
Nadler gave at the Hobbs Std. Class Nats this year (we had lots of
time for non-flying activities there). Darryl Ramm has also discussed
this. What's the best combination of hardware for a given pilot? I
cringe when I hear people say (from a different thread): "There is no
defensible rationale for failing to require everyone flying contests
to be equipped with an operating FLARM device. It contributes more to
safety than all the other pieces combined." That's very broad and
overly simplistic.

Whether to buy any type of radar/radio tracking/collision alert
hardware depends on, among other things:

1. The nature of the threat(s) and the probability thereof. At most US
national contests, the biggest threat is other gliders. At a Caesar
Creek contest squeezed up between the Cincinnati Class B and Columbus
and Dayton Class C's, however, it's not so clear. Factors include
geography--including proximity to high-traffic areas; ridge vs.
thermal vs. wave; contest vs. XC vs. local; military vs. biz jet vs.
airliner vs. general aviation traffic nearby, number of hours/flights
annually, etc. Probability factors include traffic density, typical
visibility, altitude bands, etc.
2. Pilot skill/awareness: how well does he/she search for and maintain
awareness of potential threats as well as how careful/predictable is
he/she in thermals and the entry to and exit from.
3. Existing hardware: if a pilot already has a transponder and/or a
PCAS (the "no brainer" purchases we were encouraged to make the last
few years), buying another device means not only increasing an
already considerable investment but either finding more panel space or
electrical power or making a swap. If a PowerFLARM performs the PCAS
function, the situation is simpler but not automatic.
4. Perception of the longevity of any potential purchase. I love it
when someone encourages me to buy a Mode C transponder now because by
the end of its useful life, ADS-B will be here in a big way. I'm still
flying with the LNAV that has served me well for the past 18 years.
I'm not sure what its useful life will be. Factors include technology,
regulations, implementation of proposed systems, etc. And product
offerings. FLARM was a non-issue 12 months ago in the US. Now it
should be mandatory? Please.
5. Finally, a pilot's risk profile: let's acknowledge that some are
willing to accept more risk than others (even when risk affects other
pilots and passengers). Or they are unwilling to pay as much as others
to reduce or eliminate certain risks. And risk can be defined
different ways: exposure per flight or flight hour; exposure per
flying year; etc.

I don't react well when regulators--whether the US government or the
US Rules Committee--mandate new equipment purchases. With all due
respect, contest pilots were forced to purchase two 35mm clock cameras
back in the early 90s, the clock feature of which cost an inordinate
premium over conventional cameras at the time and which was never used
at any contests I attended. A few years later, we were then compelled
to buy GPS loggers, partly on the basis that prices would drop
rapidly. The same governing body doubled down on that mandate recently
by eliminating the use of cheap, off-the-shelf GPS receivers for
contest logging backup although they've left the door open a bit.

No regulatory body, however well intentioned (and I believe our Rules
Committee guys are very much so), can predict with any accuracy the
direction that technology, regulations, or competition will take. What
CAN be predicted is that soaring will continue to decline, in part,
because of its costs. Contest flying is not immune to this. It follows
that anything that increases cost will have a small but undeniable
impact, whether on soaring in general or on competition soaring in
particular. Logic it out all you want but the demand for soaring is
not inelastic. The only differences among soaring pilots in this
regard are their own individual cost/demand curves. One person's
"$1600 is a small amount to pay for increased safety" is another
person's "I just can't afford to put any more money into soaring."

It's true that midair collisions impact soaring's popularity and even
continued viability if an airliner were to be involved. But Uvalde was
notable this year for several reasons. The first, of course, is the
tragic midair. The second is the remarkably low number of gliders in
attendance at the US's best weather site. Don't think that cost isn't
a factor, even for the competition pilots who are thought (not always
accurately) to be most able and willing to afford new gadgets.

Safety is a goal that's very difficult to argue against. After all,
who wants less safety? On the other hand, if money were no object, we
could make our sport safer by mandating ballistic recovery chutes,
cockpit exit assistance devices, and more compressible fuselage
sections; by eliminating water ballast; by requiring crash helmets in
the cockpit and the redesign work for all gliders that would entail;
and so forth.

If PowerFLARM is the clear, economical answer to most of a soaring
pilot's anti-collision problems AND collisions are deemed to be a
serious risk, then pilots will buy them in droves. Then the Rules
Committee can come in behind the trend and put their stamp of approval
on it with a new Rule, like the architects of that apolcryphal college
campus who initially allowed students to wear down their own paths in
the grass among the buildings, then came around a year later and paved
over what proved to be the most popular ones.

What I'd like to see is a matrix or decision tree or expert system
type of diagram that walks me through the purchase decision process by
answering the questions I raised above. So if my biggest threat is
other gliders in contests and fast bizjet and airliner traffic near
NYC where I fly, and if I'm concerned that I should be more diligent
at watching for traffic, and if I have no current anti-collision
hardware, and if I'm not willing to buy something unless I know it
will be useful for at least 5 years (preferably longer), and if I'm on
a budget and don't want to or can't drop several thousand bucks into
new avionics, then I should buy X because that's the sweet spot in my
cost/benefit curve.

Chip Bearden
ASW 24 "JB"
USA

Westbender

August 13th 10, 02:10 AM

On Aug 12, 4:48*pm, Dave Hoppe > wrote:
> I'm waiting for one more response regarding flarm frequency and
> approval status in the US.

And here it is:

Dave,

no problems, I'm very glad to help you!

It is a free frequency (SRD). In Europe we use 868Mhz, in the US it
will be 433Mhz. PowerFLARM automatically chooses the right frequency
for the place you are at - this means you can also use yours in europe
e.g. on competitions without having to change settings.

FCC approval is on its way and is going to be done before first units
start shipping.

Cheers
Marc

Berry[_2_]

August 13th 10, 02:51 AM

> What I'd like to see is a matrix or decision tree or expert system
> type of diagram that walks me through the purchase decision process by
> answering the questions I raised above. So if my biggest threat is
> other gliders in contests and fast bizjet and airliner traffic near
> NYC where I fly, and if I'm concerned that I should be more diligent
> at watching for traffic, and if I have no current anti-collision
> hardware, and if I'm not willing to buy something unless I know it
> will be useful for at least 5 years (preferably longer), and if I'm on
> a budget and don't want to or can't drop several thousand bucks into
> new avionics, then I should buy X because that's the sweet spot in my
> cost/benefit curve.
>
> Chip Bearden
> ASW 24 "JB"
> USA

Thank you Chip. You saved me from writing an essay covering those exact
points and saved everyone else from having to read my dreadful writing.

I'm one of those guys that is in the "I just can't afford to put any
more money into soaring..." situation. For the last 10 years, I've been
racing sports/club class with a setup that cost me less than $20k. That
includes the glider, instruments, AND the motorhome that I drag it all
around with. I know it looks like I'm a cheapo, but racing does not
account for even half of what I spend on soaring. My club gets most of
my soaring bucks. Dues, tows, little things like going halfsies on a
Pawnee...

Brian[_1_]

August 13th 10, 04:04 AM

Just want to chime in as one of the contest pilots flying on limited
budget.
In fact this I took a 5 year leave from contest flying due to budget
concerns but am happy to report that flew a regional contest this year
and am planning on doing so again in the coming years.

I too am flying a setup that cost well less the 20k.

I have to admit PowerFlarm is interesting in that in a few years it
may be good way for me to upgrade my 10 year old logger, my 15 year
old GPS and add some traffic alert capability.

Brian Case
HP16T

Mike Schumann

August 13th 10, 04:59 AM

Very well said.

It is frustrating that the obviously bright guys behind PowerFLARM
couldn't take the next logical step and make their "FLARM" RF subsystem
compatible with ADS-B UAT for the US market.

ADS-B UAT operates at 978 MHz vs 868 MHz for FLARM. The ADS-B protocol
is different than FLARM, but provides essentially the same (if not more)
functionality.

Navworx has demonstrated that it is possible to get FCC approval for an
ADS-B UAT type transceiver that conforms to the ADS-B specs, but does
not necessarily meet all of the current FAA TSO requirements, including
GPS navigational integrity, antenna diversity, etc.

I suspect that using this precedent, it would also be possible to get
FCC approval for a reduced power version, if that was necessary to hit
the required price point.

The engineering (both hardware and firmware) for such a device could
significantly benefit from the investment that MITRE has made in their
low cost ADS-B transceiver project (using our tax dollars), which they
are licensing to anyone who is interested at a VERY reasonable one-time
licensing fee.

If the PowerFLARM unit was fully ADS-B compliant (both in and out), and
provided an interface to an external display device for both traffic and
weather, many of the issues that Chip has identified would be erased.

Furthermore, a low cost version of the unit, without the PCAS
functionality, could be sold to pilots who fly in areas that are slated
for ADS-B ground station coverage. In those environments the traffic
data broadcast by the ADS-B ground stations provides much more accurate
and reliable information for transponder equipped aircraft than any PCAS
device could possibly generate.

This kind of device, at the PowerFlarm price point, would be a
blockbuster product, not only to the soaring community but in the VFR GA
power market. It would obsolete the entire Zaon PCAS product line, as
the FAA's ground station roll out gathers momentum.

--
Mike Schumann

Eric Greenwell

August 13th 10, 06:48 AM

On 8/12/2010 8:59 PM, Mike Schumann wrote:
> Very well said.
>
> It is frustrating that the obviously bright guys behind PowerFLARM
> couldn't take the next logical step and make their "FLARM" RF
> subsystem compatible with ADS-B UAT for the US market.
It may be a bit presumptuous to decide the "next logical step" for the
FLARM folks. Are you aware that besides FLARM and PowerFLARM, they also
operate SAFEmine (visit safe-mine.com)? I'm guessing they have plenty to
do with a proven device that is in widespread use (and being adapted
for other uses), and diving into the murky waters of the ADS-B market
probably looks like a poor opportunity at this time. And also because
those murky waters have some large sharks swimming in them, like Garmin
and the other aviation instrument companies.

I hope you get a chance to talk to Urs Rothacher of FLARM, as I have at
SSA conventions. I think a half hour on the phone would clear up a lot
confusion about FLARM and it's relation to ADS-B, and how much more
trouble the ADS-B out arena is compared to FLARM's niche.

--
Eric Greenwell - Washington State, USA (netto to net to email me)

- "Transponders in Sailplanes - Feb/2010" also ADS-B, PCAS, Flarm http://tinyurl.com/yb3xywl

- "A Guide to Self-launching Sailplane Operation Mar/2004" Much of what you need to know tinyurl.com/yfs7tnz

Darryl Ramm

August 13th 10, 08:58 AM

Oh man, all this whining about what could be (but isn't) or should be
(but isn't) and how everything revolves (but doesn't) around the
wonderful UAT technology. Like is there a UAT fan club people can join
for this? Can anybody join? You guy get to dress up in costumes at
your meetings? Do you have fancy hats?

Am I missing something obvious here? If you had done any of this type
of stuff before and were lecturing a failing company who had no
frigging idea what they were doing your criticisms might sit better
with me. I am sure a lot of us wish Flarm had gotten into the USA
market years ago, but my time machine is broken and I cannot fix that.
Now they are, and they are doing it with a product that also supports
ADS-B (data-in) which I think is clever and responsible.

On Aug 12, 8:59 pm, Mike Schumann >
wrote:
> Very well said.
>
> It is frustrating that the obviously bright guys behind PowerFLARM
> couldn't take the next logical step and make their "FLARM" RF subsystem
> compatible with ADS-B UAT for the US market.
>
> ADS-B UAT operates at 978 MHz vs 868 MHz for FLARM. The ADS-B protocol
> is different than FLARM, but provides essentially the same (if not more)
> functionality.
>
> Navworx has demonstrated that it is possible to get FCC approval for an
> ADS-B UAT type transceiver that conforms to the ADS-B specs, but does
> not necessarily meet all of the current FAA TSO requirements, including
> GPS navigational integrity, antenna diversity, etc.
>
> I suspect that using this precedent, it would also be possible to get
> FCC approval for a reduced power version, if that was necessary to hit
> the required price point.
>
> The engineering (both hardware and firmware) for such a device could
> significantly benefit from the investment that MITRE has made in their
> low cost ADS-B transceiver project (using our tax dollars), which they
> are licensing to anyone who is interested at a VERY reasonable one-time
> licensing fee.
>
> If the PowerFLARM unit was fully ADS-B compliant (both in and out), and
> provided an interface to an external display device for both traffic and
> weather, many of the issues that Chip has identified would be erased.

Some of the major issues Chip raised was about airline and fast jet
traffic near New York and in that situations a UAT device is very
problematic. That dichotomy, the ongoing need for transponders in some
places and a separate solution for glider-on-glider collision
avoidance etc. (and to an extent a fuzzier problem in the middle with
glider-on-GA risks) is in many ways the root of a large part of Chip's
issue. And UATs do not make that primary dichotomy go away. You can't
just keep promoting UAT boxes and ignore the transponder issue.

So around New York or similar busy airspace I would hope Chip really
gets a transponder (Mode S Trig TT21 recommended if new but even a
Mode C unit, like a used Becker unit will provide service long into
the future). So to recap again why (sorry folks here I go again...) A
UAT is not compatible with TCAS, very few airliners or fast jets have
CDTI displays (certified ADS-B based traffic displays) yet and so
cannot "see" the UAT traffic. It is unclear at what rate those
aircraft will equip with CDTI displays. Yet effectively all those
aircraft have TCAS which can "see" a transponder and the larger ones
have TCAS II that will issue an RA to avoid a collision but it must to
see a transponder signal from the threat aircraft to do that . A UAT
will make the glider visible to ATC if there is an ADS-B ground
station connected to ATC (several years for USA coverage to finish)
but so will a transponder, and that works everywhere there is ATC
service now. I am a technology geek and like some of the things ADS-B
will enable but the last thing I want to see is glider pilots thinking
UAT devices are a replacement for transponders for gliders flying near
areas of high density airline and fast jet traffic. A transponder will
also make you visible to TCAD/TAS systems in soem GA aircraft and PCAS
systems as long as something else in interrogating the transponder.
People might well wish ADS-B and UAT was going to replace transponders
but it is just not technically capable of doing that for the
foreseeable future. I really wish it was possible, but it is not.
Sorry transponders costs money, I wish they cost less, but I have
trouble arguing they are overpriced for what they do, especially a
product like the Trig TT21. Now for folks flying well away from that
kind of busy airspace, please save your money, you don't need a
transponder.

> Furthermore, a low cost version of the unit, without the PCAS
> functionality, could be sold to pilots who fly in areas that are slated
> for ADS-B ground station coverage. In those environments the traffic
> data broadcast by the ADS-B ground stations provides much more accurate
> and reliable information for transponder equipped aircraft than any PCAS
> device could possibly generate.

The PowerFLARM will do TIS-B in a future firmware update. In a 1090ES
receiver the PCAS won't add significant unit cost, it will be all
fixed cost for software. And unlike TIS-B this provides some coverage
outside of ATC radar coverage and seems quite a few of us already use
PCAS systems working in many of those areas. I expect some other
vendors doing 1090ES receivers (esp. portable/non IFR receivers) to
also do PCAS as well like this because it works in all countries, it
works in the USA prior to widespread GBT deployment, unlike TIS-B it
works outside current radar coverage volumes (as long as you have
other transponder interrogators) and all the hardware you need is
already there in the 1090ES receiver for free. Its a nice to have
feature, and a beautiful competitive marketing tool to use to
effectively displace current PCAS products/uses if you can just say
your box does everything they do and a lot more (well at least for
Zaon MRX type devices). Smart marketing.

> This kind of device, at the PowerFlarm price point, would be a
> blockbuster product, not only to the soaring community but in the VFR GA
> power market. It would obsolete the entire Zaon PCAS product line, as
> the FAA's ground station roll out gathers momentum.

Some GA pilots will buy a PowerFLARM as is but it is really a
different market, you need different focus, compatibility with
different displays, different feature sets (is an IGC flight recorder
of significant differentiation to most GA pilots? Wouldn't they much
rather want Garmin TIS display support?), etc. I've got a background
in getting new high-tech products to market and part of what I do is
consulting to startups and investors. One thing that makes me happy to
find is young companies with a focus on depth not width, an inane
knowledge of and focus on a customer base where they can be successful
and then longer term ability to grow into new/broader markets. Go read
Geoffrey Moor's "Crossing the Chasm", that gives a good lay-
perspective on entering new markets for technology companies. Flarm is
a small company, but to me has all those good focus characteristics,
and is played right the ability to grow into new markets. And they are
making choices like including an ADS-B 1090ES receiver in the
PowerFLARM that does allow interesting future market applications
(worldwide, not just the USA), many with just software additions/
changes.

The "obviously smart guys at Flarm" have an actually working glider-on-
glider and glider-on-towplane collision warning technology proven over
years or use. They have a custom developed radio protocol tuned to the
needs of gliders in avoiding mid-air collisions. They have lots of
academic and practical research on making this stuff really work. And
they have the ability to improve that protocol as they have done in
the past at their own pace. If I was them the absolute last thing I
would want to do is tie myself to be being dependent on a slow moving
inflexible bureaucratic process, and including in the USA a very
complex dual-link system with ground based processing. Yet they are
also smart enough to realize that in the future broader aviation
traffic awareness systems are going to be based on ADS-B and they have
a product in the PowerFLARM that can interact in both their own
specialized environment, and just work off the shelf today, and
provide ADS-B data-in for that broader interoperability.

Most of the rest of the world does not care about UAT technology. It's
largely an FAA aberration. Mmm lets see, a UAT based product aimed at
gliders. Well not much market there outside maybe a few hundred USA
glider pilots. Well not unless somebody convinces the FAA to make UATs
mandatory for gilders, hang gliders, parachutists, etc. Boy I hope
nobody here wants to see that blanket regulatory requirement.

Those "obviously smart guys at Flarm" probably understand the benefits
of market differentiation in the glider market, where they dominate,
and appreciate that the "Crossing the Chasm" challenge of entering a
larger market with different needs is non-trivial. But to me it looks
like they are kind of already planting the seeds for some new
applications with the ADS-B receiver capability in the PowerFLARM.
Seems pretty smart to me.

If the UAT efforts underway manage to produce low-cost UAT
transmitters and receivers that is great, that should be goodness for
some of the lower-end aviation market in the USA. Including in gliders
where it could make a perfectly good UAT transmitter to be used with
some of the PowerFLARM ADS-B receivers. And I hope that actually
happens, a great long slow process to solve all those UAT transmitter
issues, probably good stuff for other companies to take the lead on.

Sigh.

Darryl