Originally Posted by
BluSdUp
The transponder is suppressed on ground.
Most types are switched on/ off on nosewheel squat switch.
If you dont believe me watch the guy racing down the rwy on takeoff next time you are on short final!
You can see him but TCAS cant. And voila he lifts, and there he is.
Same on landing behind a fella: Now he is there, now he is gone, ie on the runway, no more mode A and C.
so the note on the FAA plans regarding ASDE-X is useless?
"ASDE-X in use. Operate transponders
with altitude reporting mode and ADS-B
(if equipped) enabled on all airport surfaces."
for example to find here:
http://aeronav.faa.gov/d-tpp/1803/00...nameddest=(JFK)
so it seems TCAS does the suppression because in mode-s on-ground is transmitted in the transponder response.
my guess would be switching ta/ra off means your TCAS isn't needlessly querying other transponders.
maybe this document can shed light on it ...
https://www.eurocontrol.int/sites/de...t-20050403.pdf