Originally Posted by
peekay4
That assumes all aircraft have operating transponders, which might not be the case. There are many GA aircraft without transponders, or one might be inop, or a student pilot who accidentally left it at STBY, etc.
I have never seen any GA aircraft without transponders at FL360...
...but then again, it could surely happen.
Airmanship and SA goes hand in hand. No SA, outside controlled airspace and with more than one target on TCAS, sure I will follow it, but if only one target at FL360 in controlled airspace and visual (since 80 miles in the contrails) plus maybe SA from ATC communication, I will assume the responsibility and ensure positiv separation by creating line of sight to the other aircraft.