Flarm in the US

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

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 |

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 |

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.

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

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

....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

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

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 hardwa 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

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