Just 'cause I'm trying to follow in context here... is it an estabished fact that an aircraft involved in the collision was in a place in the circuit, which was not where they should have been? Obvioulsy two aircraft were in the
same place, but was either in the
wrong place, were the other not to have been there? Are there any facts?
if circuit inactive, no one about, great. If the circuit is active then, clear intentions to all and sundry about what you are about to do, is/should be mandatory
At a controlled airport, I can see how this works, but then you have a controller who is aware that you are doing something unusual, and has "controlled" the airspace to safely enable it. I extend to the controllers (I think Shoreham is positively controlled?) the belief that if they had known there was a prospect of conflict, would have advised.
One of those MD500's could depart on the runway heading, manage a climb better than the RV-X, and probably be even harder to see while doing it. Would the MD500 pilot be wrong to accomplish a maximum performance climb on the runway axis? Is there a limiting procedure for this? I've never seen one. Indeed, the reverse at some airports, "no turns until X feet AGL". Let's get the noise as far up as possible, as fast as possible, Particularly for helicopters, 'cause the airport has neighbours, and we pilots are trying to mitigate annoyance.
At an uncontrolled airport, how would you ever know if the circuit is inactive? I think that is an assumption which can never be made. I fly a nordo aircraft into an uncontrolled airport from time to time. I spend the entire time watching out like crazy, and flying something predictable as a pattern. I never assume the circuit is inactive! Indeed this airport has two simultainious parallel circuits, one to the right, the other to the left, and it works quite well, as long as you assume both are active, and fly accordingly.
Just my opinion..... but...All of the circuit procedure posturing here is only touching a part of the real world circumstances, while other realities are being completely overlooked. While flying a helicopter into a controlled airport, no controller has ever asked me to conform to the airplane circuit, even though palnes were in it. When I tried, it seemed to introduce confusion!