Nigel and others
I have been giving a little more thought to TCAS and CAS within the GA enviroment. I would be interested in everyones comments.
So, we are agreed the POH says you should visually acquire the traffic BEFORE taking avoiding action. Skywatch, in a similiar way to full TCAS, paints a bubble around the aircraft. In Skywatch's case if an aircraft enters the bubble you will get an audible warning and the display will indicate the height and position of the traffic relative to you, together with the positional trend of the traffic. You do NOT get an RA at any time.
Here is the scenario.
You are en route and not receiving a RIS. Its VMC but 4K. You note on TAS traffic at exactly the same level at a range of 10K which will cross your track line converging at right angles. You are flying at 175knts and the other traffic is at a similiar speed.
What do you do? Do you do anything until you have acquired the traffic visually?