Keep in mind that Helicopters do not abide by the same rules as UAVs and for that matter fixed wing aircraft, they pretty much fly where and when they want, had there been a collision surely the UAV will be found at fault for not yielding to the maned aircraft. I had a very close call with an amphibious plane who came in for a landing on the bay over the park where I was flying where he was at 200 ft or so quickly depending to 100 where I was and flew maybe 50 yards from me, unfortunately I couldn't react fast enough to catch it on video as it blew by me as I was turned in the oposite direction and I only caught him as he was touching down. That is common behavior for these pilots, mind you area was not flagged by DJI (my buddy was flying a mavic) as a no fly or even a warning zone.