[USNBandit]

From what I've heard the helicopter was climbing out from the heliport up to the plane's altitude. From the perspective I think it would have been tough for the plane to pick up the helicopter due to the nose of the aircraft and the height of most general aviation instrument patterns.

The flip side is that an AS350 is probably climbing out at somewhere between 60 kts and 90 kts with the plane at it's 4 o'clock high.

My understanding is that there is a common traffic frequency that people are supposed to use. That allows pilots to report regular reporting points and for the helicopters to report when lifting. I cannot believe that the helicopter pilot wouldn't be up that freq. If he didn't hear any response while he was lifting then he probably thought the airspace was clear.

[jwparkerjr]

I saw one report where another helicopter pilot advised the accident aircraft that there was someone approaching from behind. The pilot said he got no response from the other aircraft.