On Aug 18, 11:31*pm, Darryl Ramm wrote:
On Aug 18, 8:32*pm, Andy wrote:





On Aug 18, 10:04*am, jcarlyle wrote:

Vacation made me late for this thread. Mike Schumann was curious if
any Trig transponders were "interfaced with a GPS navigation source
and being used for ADS-B out", and Darrl thought that there was one in
a glider, in addition to the FAA installation.

I've had my Trig TT21 flying with 1090ES data-out for just over a
year. The GPS source is my Volklogger, and the GPS Integrity Level is
set to Low. The VFR transponder check verified that squitters were
being sent.

I plan to have the Trig's firmware upgraded soon, so it'll be possible
to turn on the 1090ES data-in capability bit. That way, when my
PowerFLARM arrives, I'll be set to look at ADS-B traffic around me -
and also set to receive TIS-B traffic when PowerFLARM updates their
firmware in the summer of 2011.

-John

I thought the only disadvantage of 1090ES vs UAT was that the former
couldn't receive TIS-B traffic. If it's true then why wouldn't the
ultimate future-proofed solution be a TT21/22 and a PowerFlarm. *You
can get them both within a few months and the will provide the best
coverage through the transition. *That plus with 1090ES being
mandatory in 2020 for big iron you have optimal solutions against the
two scariest threats (other gliders because of the density and
proximity issues in remote locations and airliners because hitting one
of those is a buzz-kill for the whole sport). At the same time you get
PCAS to cover all the slow adopters. Plus you get integration into
glider nav systems and glider-specific collision modeling.

What did I miss?

9B

Andy you were thinking of FIS-B (not TIS-B) only being provided by a
UAT receiver. FIS-B is weather, TFR, NOTMAM etc. basically like XM
weather (free but not quite as capable, at least today).... And you
can't have that in a contest even if you want it. :-)

BTW ADS-B products used in contests are going to be "interesting" for
the poor CD to deal with, ... not just worry about somebody getting
weather reports. I'd expect Flarm to have that though out given their
existing "stealth mode" and logging of that mode setting. Any other
ADS-B receiver being proposed into contest glider cockpits would needs
some form of similar setting, and either a tamper proof way to set
that on the ground or a way to log if a pilot changes it. I don't see
that ever happening with a GA device and if the ADS-B receiver (like
the Mire UAT prototype) is relying on a serial data link and an
external device like a PDA running third party traffic display/warning
software then it's probalby hard to make that not easily hackable. And
every third party software package reading that data would need to
have settings/ways of checking known and trusted by rules committees/
contest directors. The smarts that does the "stealth mode" selective
filtering/fuzzying up of received data really needs to live within the
box, effectively also meaning that the alert software also needs to
live within that box and not on an external system --as you probalby
need the alert system having access to the raw unfuzzied/unfiltered
data.

Darryl

Also - I agree the contest requirements argue heavily for a glider-
specific solution - most likely PowerFlarm in the US, since the
unfiltered ADS-B technology would lead to leech-heavy contest
behavior. I would expect it to be banned in much the same way we ban
artificial horizons.

9B