Originally Posted by
russian roulette
A and C
Agree with TCAS - that can be a personal choice. No one is advocating TCAS for all, but Mode C for all is inexpensive and lightweight.
And, yes of course there can be a collision if the RA is not followed. You could say the same about a stick shaker - people have pulled instead of pushed !
Many smaller aircraft operated in Class G already have ACAS/TCAS I or TAS but that version only gives TA, not RA. I've been using it for almost 20 years and would feel very vulnerable now without it. It has to be used in context, the most relevant aircraft might not appear on it for reasons already known and so it must be used to assist lookout, never to replace it. It works very well as long as it's limitations are understood. It's proved to me many times that lookout alone is very often inadequate, due to human limitations. I've lost count of the number of occasions when other pilots had a clear obligation under the rules of the air to take necessary avoiding action from our aircraft, but completely failed to do so because they obviously never saw it. So we are always prepared to take action instead. Thankfully TCAS gives good advance warning so we can (and very often do) avoid a conflicting flight path by taking early action.
I posted on this forum very many years ago to explain that the full use of the transponder with mode c where fitted was a great asset to safety because a TCAS equipped aircraft could "see" other aircraft well beyond the range of human eyesight. I got heavily criticised by some who claimed I was using it as an excuse not to look out and even by some who considered the use of a transponder a breach of their human right to remain anonymous in flight!