Originally Posted by
ahramin
I think it depends on whether or not the aircraft is in radar airspace. The TCAS II may not be using Mode A interrogations but the Secondary Surveillance Radar is and TCAS II will see the replies to those interrogations.
Hi Ahramin
I don't understand what information can be gained from the mode A reply, by a unit that didn't transmit the interrogation signal?
Cheers
TeeS