TCAS equipped aircraft will receive RA's when in conflict with non TCAS traffic so long as that aircraft has a functioning mode "C" transponder
Oh dear. I'd better dig those books out and do some revision then, because that's not the way I recall it from my studies!
That minor mistake aside, though, it seems I am correct in thinking that having Mode S would give no advantage, from a TCAS point of view, over having Mode C.
Thanks.
FFF
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