Flarm in the US

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

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.

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

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

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

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

http://faculty.chicagobooth.edu/john...ers/flarm.html

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

John Cochrane

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...ers/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

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 the

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

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 the

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

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 the

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