Build your own PowerFLARM!

On 8/16/2010 6:13 PM, Brian wrote:

PowerFlarm is ADS-B In only. It only transmits FLARM, which jets can't
see. By itself it does absolutely nothing to protect us against
mid-airs against jets.

--
Mike Schumann- Hide quoted text -

except that it will tell you the jet near you before you mid-air if I
understand correctly
"transponder PCAS annunciation."

Unless you are transmitting ADS-B Out, all you get is a warning that
someone is near you at your altitude. You get altitude and distance,
but not a clue of which direction they are coming from. The jet and his
TCAS doesn't see you at all.

--
Mike Schumann

On Aug 16, 5:14*pm, Mike Schumann
wrote:
all you get is a warning that
someone is near you at your altitude. *You get altitude and distance,
but not a clue of which direction they are coming from.

Having flown with the ZAON MRX for 2 seasons I find that alerting to
be useful. Certainly much more useful than "absolutely nothing to
protect us ".

As mentioned previously PowerFLRAM has the opportunity to be a big
improvement over the MRX if they include target specific alert
suppression. (let me mute the gliders I am thermalling with and still
be alerted to the B737 or King Air that is about to mow us all down)

Andy

On Aug 16, 8:14*pm, Mike Schumann
wrote:
On 8/16/2010 6:13 PM, Brian wrote:

PowerFlarm is ADS-B In only. *It only transmits FLARM, which jets can't
see. *By itself it does absolutely nothing to protect us against
mid-airs against jets.

--
Mike Schumann- Hide quoted text -

except that it will tell you the jet near you before you mid-air if I
understand correctly
"transponder PCAS annunciation."

Unless you are transmitting ADS-B Out, all you get is a warning that
someone is near you at your altitude. *You get altitude and distance,
but not a clue of which direction they are coming from. *The jet and his
TCAS doesn't see you at all.

--
Mike Schumann

If I have a warning, I have a chance.
I'm convinced he will not avoid me.
UH

On Aug 16, 2:39*pm, Mike Schumann
wrote:

So rather than poo-poo any ADS-B solution, why not encourage people like
See-You, Clear Nav, and others to support both platforms and let the
best solution win.

Mike - Believe it or not, we're not "poo-poo"ing your precious Navworx
box. I think what most people are convinced of is that an ADS-B Out
box is not a sufficient solution. They want something that covers a
broad spectrum of signals and is also tuned for glider usage. The
PowerFLARM system fits this well. You are correct - the PowerFLARM
unit has not shipped; but it is being produced by a company that
already has thousands of devices sold & in-use, which lends confidence
in their ability to pull it off. By comparison, what company has
produced and sold a similar number (15,000+) of ADS-B units?

Oh, and I believe SeeYou and many other PDA/Flight-Computers already
support the FLARM protocol. If they support ADS-B systems as well,
great!

--Noel

On 8/16/2010 7:47 PM, Andy wrote:
On Aug 16, 5:14 pm, Mike
wrote:
all you get is a warning that
someone is near you at your altitude. You get altitude and distance,
but not a clue of which direction they are coming from.

Having flown with the ZAON MRX for 2 seasons I find that alerting to
be useful. Certainly much more useful than "absolutely nothing to
protect us ".

As mentioned previously PowerFLRAM has the opportunity to be a big
improvement over the MRX if they include target specific alert
suppression. (let me mute the gliders I am thermalling with and still
be alerted to the B737 or King Air that is about to mow us all down)

Andy


Does anyone have any detailed technical data on how PowerFLARM is able
to distinguish a Mode C transponder equipped glider from a Mode C
transponder equipped powered aircraft?

ATC radar can track an individual Mode C transponder equipped aircraft,
because it can not only see the range and altitude of the aircraft's
location, but also the bearing. The PowerFLARM unit can not track the
transponder bearing, so some healthy skepticism is in order on the claim
that they can intelligently suppress glider induced false alarms while
not inadvertently also suppressing some real collision threats.

--
Mike Schumann

On Aug 16, 4:41*pm, Mike Schumann
wrote:
On 8/16/2010 4:22 PM, noel.wade wrote:



On Aug 16, 1:49 pm, wrote:

As I understand it, Power Flarm will incorporate ADS-B ( protocall not
completely clear to me) as well as transponder PCAS annunciation.

Here's a short Not-Totally-Technically-Accurate-But-Close-Enough
Explanation:

There are two "flavors" of ADS-B: *1090ES and UAT. *The 1090ES system
is more likely to be used by big/fast airplanes. *UAT is more likely
to be equipped on small GA aircraft. *PowerFLARM supports 1090ES. *It
does not support UAT or ground-based relays of traffic information
(according to the specs released so far). *So you'll see some ADS-B
aircraft with the PowerFLARM; but you won't necessarily detect _every_
ADS-B aircraft. *I believe that "some" ADS-B detection is better than
"none", especially when you add in the ability to see Mode C/S
transponders (when replying to radar pings) and other FLARM-equipped
gliders.

--Noel
(who will have a PowerFLARM this fall)

PowerFlarm is ADS-B In only. *It only transmits FLARM, which jets can't
see. *By itself it does absolutely nothing to protect us against
mid-airs against jets.

--
Mike Schumann

Mike, what is your agenda? You seem determined to trash the potential
right-now benefits of PowerFlarm for the dubious future advantage (to
glider pilots) of ADS-B (specifically the REALLY stupid UAT part of
it). Worried about an airliner hitting you and not smart enough to
look out the window when PCAS tells you there is a big jet nearby? Get
a Mode S transponder. Or you can look at a chart and figure out the
arrival and departure routes of the local airlines and look in that
direction when you get a PCAS warning! Ditto lightplanes - they are
most likely cruising at VFR or IFR hemispheric altitudes, so if the
relative alitude is not changing, look in that direction! (Unless your
altimeter is set to QFE, of course....) What I want a FLARM device
for is to warn me of the not so random presence of other GLIDERS!

Here is a simple mental exercise: 2 power planes takeoff from the
same airfield. No coordination between the two. What is the
probability that they will have a midair? Now, two glider launch from
that same airfield, on a good soaring day. What is the probability
that they will have a midair? Let's see, the power planes have all
day to pick a time to go, and they can go in any direction, at pretty
much any altitude, to pretty much any destination. OTOH, the gliders
will likely launch at about the same time, and go the the best lift,
fly in the same altitude band, and return at roughly the same time.
THATS WHY ADS-B IS LESS IMPORTANT TO GLIDERS THAN FLARM!

And on the ridge on a good day? Yikes!!! 200knot closure, 50 feet
above the trees. Yeah, ADS-B is going to be lots of help there!

But here is a question: PowerFlarm claims it can detect ADS-B 1090ES
signals and provide bearing/rangealtitude info; it's just the legacy
Mode C transponders that will only give a range/relative altitude
warning (similar to PCAS). Are you saying that this is not possible
and that you also need a UAT in/out box to detect Mode -S equipped
1090ES ADS-B participants? I understand that with only a Powerflarm
you won't see UAT - only participants - but since they will probably
still need Mode C even that isn't true - you are just down to PCAS
level of detection. Please correct me if I'm wrong on this.

Finally, all this reminds me of my days sailing a Laser in the
Intercoastal waterway - sure I had right of way over the big barges
in the shipping channel, but no way was I going to push it! Ditto
airliners. If you are so clueless that you miss an airliner coming at
you on a VFR day, when you should know where he is coming from, and
have a 5 or more mile warning from your PCAS or PowerFlarm, you
shouldn't be flying there! Or just pony up for a Trig and be done
with it!

Finally, how about SSA working on the insurance companies to give
pilots who fly with anti-collision devices and transponders a break on
their insurance? I read somewhere Italy does that for FLARM. A 10%
reduction on my annual premium would go a long way!

Rant off/

Kirk
66
Saving my pennies for a PowerFlarm for next season (and a Trig in the
future) but not holding my breath for UAT or ADS-B

On 8/16/2010 10:50 PM, kirk.stant wrote:
On Aug 16, 4:41 pm, Mike
wrote:
On 8/16/2010 4:22 PM, noel.wade wrote:



On Aug 16, 1:49 pm, wrote:

As I understand it, Power Flarm will incorporate ADS-B ( protocall not
completely clear to me) as well as transponder PCAS annunciation.

Here's a short Not-Totally-Technically-Accurate-But-Close-Enough
Explanation:

There are two "flavors" of ADS-B: 1090ES and UAT. The 1090ES system
is more likely to be used by big/fast airplanes. UAT is more likely
to be equipped on small GA aircraft. PowerFLARM supports 1090ES. It
does not support UAT or ground-based relays of traffic information
(according to the specs released so far). So you'll see some ADS-B
aircraft with the PowerFLARM; but you won't necessarily detect _every_
ADS-B aircraft. I believe that "some" ADS-B detection is better than
"none", especially when you add in the ability to see Mode C/S
transponders (when replying to radar pings) and other FLARM-equipped
gliders.

--Noel
(who will have a PowerFLARM this fall)

PowerFlarm is ADS-B In only. It only transmits FLARM, which jets can't
see. By itself it does absolutely nothing to protect us against
mid-airs against jets.

--
Mike Schumann

Mike, what is your agenda? You seem determined to trash the potential
right-now benefits of PowerFlarm for the dubious future advantage (to
glider pilots) of ADS-B (specifically the REALLY stupid UAT part of
it). Worried about an airliner hitting you and not smart enough to
look out the window when PCAS tells you there is a big jet nearby? Get
a Mode S transponder. Or you can look at a chart and figure out the
arrival and departure routes of the local airlines and look in that
direction when you get a PCAS warning! Ditto lightplanes - they are
most likely cruising at VFR or IFR hemispheric altitudes, so if the
relative alitude is not changing, look in that direction! (Unless your
altimeter is set to QFE, of course....) What I want a FLARM device
for is to warn me of the not so random presence of other GLIDERS!

Here is a simple mental exercise: 2 power planes takeoff from the
same airfield. No coordination between the two. What is the
probability that they will have a midair? Now, two glider launch from
that same airfield, on a good soaring day. What is the probability
that they will have a midair? Let's see, the power planes have all
day to pick a time to go, and they can go in any direction, at pretty
much any altitude, to pretty much any destination. OTOH, the gliders
will likely launch at about the same time, and go the the best lift,
fly in the same altitude band, and return at roughly the same time.
THATS WHY ADS-B IS LESS IMPORTANT TO GLIDERS THAN FLARM!

And on the ridge on a good day? Yikes!!! 200knot closure, 50 feet
above the trees. Yeah, ADS-B is going to be lots of help there!

But here is a question: PowerFlarm claims it can detect ADS-B 1090ES
signals and provide bearing/rangealtitude info; it's just the legacy
Mode C transponders that will only give a range/relative altitude
warning (similar to PCAS). Are you saying that this is not possible
and that you also need a UAT in/out box to detect Mode -S equipped
1090ES ADS-B participants? I understand that with only a Powerflarm
you won't see UAT - only participants - but since they will probably
still need Mode C even that isn't true - you are just down to PCAS
level of detection. Please correct me if I'm wrong on this.

Finally, all this reminds me of my days sailing a Laser in the
Intercoastal waterway - sure I had right of way over the big barges
in the shipping channel, but no way was I going to push it! Ditto
airliners. If you are so clueless that you miss an airliner coming at
you on a VFR day, when you should know where he is coming from, and
have a 5 or more mile warning from your PCAS or PowerFlarm, you
shouldn't be flying there! Or just pony up for a Trig and be done
with it!

Finally, how about SSA working on the insurance companies to give
pilots who fly with anti-collision devices and transponders a break on
their insurance? I read somewhere Italy does that for FLARM. A 10%
reduction on my annual premium would go a long way!

Rant off/

Kirk
66
Saving my pennies for a PowerFlarm for next season (and a Trig in the
future) but not holding my breath for UAT or ADS-B

A. "Right Now Benefits of PowerFlarm" - This product does not currently
exist. Has it been submitted to the FCC for approval yet? What is the
expect ship date?

B. 1090ES ADS-B - You aren't going to see anything on PowerFLARM unless
you are also equipped with, and transmitting a properly configured ADS-B
Out Signal. That part is NOT provided by PowerFLARM.

C. PCAS - How does PCAS tell you anything about what kind of target is
aiming for you? In fact, it doesn't give you any information on where
the target is, whether it's getting closer or moving away. All you know
is altitude and range (NO bearing). It's not going to tell you if it's
a jet, another glider, or your tow plane. And you are only going to get
that much info if the transponder equipped plane is being interrogated.
That's not a given if you are flying low in remote areas without radar
coverage.

What's my agenda? Making sure that people know what they are buying and
the limitations thereof.

--
Mike Schumann

On Aug 16, 7:35*pm, Mike Schumann
wrote:
On 8/16/2010 7:47 PM, Andy wrote:



On Aug 16, 5:14 pm, Mike
wrote:
* all you get is a warning that
someone is near you at your altitude. *You get altitude and distance,
but not a clue of which direction they are coming from.

Having flown with the ZAON MRX for 2 seasons I find that alerting to
be useful. *Certainly much more useful than "absolutely nothing to
protect us ".

As mentioned previously PowerFLRAM has the opportunity to be a big
improvement over the MRX if they include target specific alert
suppression. (let me mute the gliders I am thermalling with and still
be alerted to the B737 or King Air that is about to mow us all down)

Andy

Does anyone have any detailed technical data on how PowerFLARM is able
to distinguish a Mode C transponder equipped glider from a Mode C
transponder equipped powered aircraft?

It cannot. You should know that Mode C includes no identification
about aircraft type or other information. But that is not what Andy
was saying.

Andy was pointing out PowerFARM has detection type suppression (e.g.
suppress PCAS and just tell me about Flarm threats.) Contest pilots
will absolutely need this in large gaggles if a reasonable number of
those gliders have transponders (esp. Mode C).

ATC radar can track an individual Mode C transponder equipped aircraft,
because it can not only see the range and altitude of the aircraft's
location, but also the bearing. *

The PowerFLARM unit can not track the
transponder bearing, so some healthy skepticism is in order on the claim
that they can intelligently suppress glider induced false alarms while
not inadvertently also suppressing some real collision threats.

Again that was not what Andy was claiming.

But issues with transponders in gaggles really has little to do with
tracking direction, there is no directional PCAS (i.e. Zaon XRX) or
TCAD or TCAS system that has a hope in hell of working in a really
crowded gaggle type environment. Especially not one with a good
fraction of those gliders having Mode C transponders. That is what
Flarm is for.

Please no hate mail from PCAS users, I have a Zaon MRX and love it as
well, but things will hit the wall in crowded environments.

The PowerFLARM PCAS capability as a very nice adjunct to it's Flarm-
Flarm capability, handy out on course against transponder equipped
gliders and against GA traffic etc.

--
Mike Schumann

Yes we know.

Sigh.

Darryl

While in a glider, I want to be alerted to other traffic whether it is
a glider, light airplane, heavy jet or business jet, so that I can
look for and possibly avoid it.
I do not want to hope that it is equipped with TCAS and count on the
other pilot being alerted to my transponder presence and avoid me. My
glider is much less visible than any other aircraft so I will have
the better chance of seeing and avoiding the traffic. For this reason
I feel the Zaon Pcas is enough protection for glider to airplane
collision threat. However, Powerflarm (when available) is a better
solution for areas were there is a high concentration of gliders (more
than 1 actually). When thermalling or ridge soaring, I do not want to
be allerted every time a glider is with in 3 miles of me. I only want
to be alerted to the one that poses a high threat of collision. I do
want to be alerted to transient airplane traffic with in 3 miles. So
in my world, I would not install transponders in gliders unless the
glider was operated in airspace where transponders were required.
I sell, install and certify transponders in gliders and I think they
are reasonable tools to have but I will fly with and equip my fleet
gliders with PowerFlarm.
Rex
Williams Soaring Center

On Aug 16, 8:50*pm, "kirk.stant" wrote:
On Aug 16, 4:41*pm, Mike Schumann
wrote:
[snip]

But here is a question: *PowerFlarm claims it can detect ADS-B 1090ES
signals and provide bearing/rangealtitude info; it's just the legacy
Mode C transponders that will only give a range/relative altitude
warning (similar to PCAS). *Are you saying that this is not possible
and that you also need a UAT in/out box to detect *Mode -S equipped
1090ES ADS-B participants? I understand that with only a Powerflarm
you won't see UAT - only participants - but since they will probably
still need Mode C *even that isn't true - you are just down to PCAS
level of detection. *Please correct me if I'm wrong on this.

Kirk let me try to give you a useful answer to your actual questions.
Let me know if I do not cover them all enough.

Also see my more technical post in the "Flarm in the USA" thread
(Google News users see if this link works... http://bit.ly/9jOA1p)

The PowerFLARM 1090ES receiver will "see" ADS-B 1090ES data-out
equipped aircraft aka "ADS-B Direct". Which means you will start
seeing some early adopter 1090ES equipped traffic now and by the end
of this decade you will see all airliners, all fast jets, all
turboprops, and many high performance singles and twins - they all get
caught in the above FL180 requirement for 1090ES data-out in the 2020
carriage mandate. I expect you will also directly see most mid-range
and above GA aircraft as I expect many of those will meet ADS-B data-
out requirements by upgrading their Mode S transponders with 1090ES.
We'll have to wait and see what actually happens in that lower-end
market.

The PowerFLARM will see Mode C and Mode S transponders via (non-
directional) PCAS if those transponders are being interrogated by an
external source (SSR radar, TCAS, TCAD etc.). Mode S transponders that
have 1090ES data-out would be seen via 1090ES and the PowerFLARM
should automatically suppress the PCAS alert for that threat (its
technically trivial and obvious to do that).

Kirk you are correct in that UAT data-out equipped aircraft will
likely have a transponder and therefore a PowerFLARM would see them
via PCAS (if the transponder is being interrogated). Aircraft flying
in airspace that requires them to have ADS-B also requires them to
have transponders. So I expect the common configs to be Mode S with
1090ES or UAT with Mode C. Although you could have both UAT and ModeS/
1090ES or Mode S (with no 1090ES)and UAT. Powered aircraft not
required to have transponders because they don't fly in/near
controlled airspace/above 10,000' etc might voluntarily equip with UAT
only (no transponder) over time to get benefits of ADS-B data-in. But
I expect this to be a small group (who wants to build up an expensive
panel but limit severely where the aircraft can fly).

Without an ADS-B transmitter you will not reliably receive ADS-R (ie.
you won't reliably see any other UAT data-out equipped traffic) or TIS-
B (ie. you won't see the ADS-B relay of SSR radar position data for
other aircraft. And TIS-B only works where there is current SSR ATC
radar coverage). By not reliably, I mean you *really* need an ADS-B
transmitter if you you want to receive TIS-B or ADS-R. You may see
some TIS-B and ADS-R aircraft near other ADS-B data-out equipped
aircraft just not near you - not a good thing. And the danger for
people who do not understand what is going on is they will see some
ADS-B traffic on their ADS-B receiver system. But not realize they
could be missing lots of ADS-R and TIS-B traffic if they don't have a
(correctly configured) ADS-B transmitter.

TIS-B will be interesting as it can give you pretty nice traffic
information if you fly where there is radar coverage (and high enough
to be in that coverage). You also need ADS-B ground station coverage
for this to work - which is rolling out over the next few years for
the entire USA.

As pointed out by people in other threads the PowerFLARM will add TIS-
B support some time after first availability, and so until TIS-B is
supported at all in PowerFLARM it is irrelevant whether you have a
transmitter or not. There are very few UAT data-out equipped aircraft
yet so ADS-R is likely not that interesting (existing UAT deployments
up to now have been mostly in Alaska in ADS-B trials).

And to be clear the challenge here will not be PowerFLARM receiving a
TIS-B data message its working out how to effectively warn about that
traffic with as few false alarms as possible with the inherently less
precise location information that a TIS-B threat has (because the
threat location comes from SSR radar). So somebody could jump up and
down now and claim their UAT or other box receives ADS-R and
PowerFLARM does not. That claim really requires looking at details of
how the internal or external traffic display and threat warning part
handles TIS-B threats.

---

OK now some more editorializing...

Personally if I had to chose only to have an ADS-B receiver I'd much
rather have a 1090ES receiver than a UAT receiver because starting now
and getting better over time it will show 1090ES equipped airliners
and fast jets directly and over a long range and all altitude
difference (the display software always needs to let you limit that -
I don't know what PowerFLARM does there, I trust them to get it right
or it to be what glider pilots need). As better/cheaper/smaller/etc.
UAT transmitters or transponders and the GPS systems to drive become
available I can add that device and do full ADS-B.

With a UAT receiver only and no transmitter you won't reliable receive
position data from airlines, fast jets or high-performance singles.
But then if you go the next step and install an ADS-B transmitter (UAT
or 1090ES) you will only be guaranteed of seeing TIS-B and ADS-R
threats that are wihtin the "service volume" around your aircraft,
typically +/- 3,500' and within 15 nautical miles of you (there may be
velocity/time to enter threat volume enhancements of this like there
is for Mode S TIS, but good luck finding out how that works). I'd just
much rather directly receive the 1090ES ADS-B data-out from the big
fast airliners and fast jets. I might feel differently if I was
worried about a lot of GA traffic with UAT data-out. But I'm not sure
that UAT data-out is going to get much penetration in GA at all, we'll
have to wait and see.

I am not advocating relying on traffic awareness tools in the glider
cockpits as the the primary technology adjunct near high density
airliner and fast jet traffic - for that the best idea is put a Mode C
or Mode S transponder in your glider and let the combination of ATC
and TCAS II look out for you. A TCAS II RA likely gets anybody's
attention off the rental car reservations and back on flying the jet,
or at least just doing what the RA tells them.

In the USA ADS-B is going to roll out big time this decade, but right
now it still is mostly futureware. Nice neat geek stuff for early
adopters to worry about now. On the other hand I'd be concerned to
see hundreds of glider pilots in the USA rushing out now to buy Flarm
classic (Flarm protocol only) units even if they were available in the
USA (which they are not). Those pilots will likely be pleasantly
surprised what PCAS can do now outside of crowded contest
environments, and how 1090ES direct can show them some traffic and
what more they can get if they want to add ADS-B data-out in future.

The USA is different from Europe and other places where gliding is
popular, we don't have any flarm adoption here yet, and yet we are the
most advanced ADS-B strategy and rollout happening from GA up to
airliners. I really like that PowerFLARM combines both. (And to be
very clear by "most advanced" here I mean in terms of having
regulations in place that require so many aircraft to equip with ADS-B
data-out on a hard time line (by 2020), not "most advanced" as in
actually being a more sensible or coherent ADS-B or airspace strategy
compared to other locations like Europe.).

Hope that all helped.


Darryl