Witnesses reported that the pilot landed and was planning on exiting the helicopter to perform a "fluid level check." After landing, the pilot exited the running helicopter; shortly thereafter the helicopter became airborne without the pilot at the flight controls.
I have some doubts about the way this has been reported.
For instance, how would witnesses know the pilot's intentions? Did he stroll over to them and explain this? If not then that statement must surely be speculation - i.e. guesswork at best.
What on earth is a "fluid level check"? I've never heard of such a thing.
How could a helo possibly get airborne at ground idle - or did he get out with Nr at 100% - which sounds too far-fetched to be even considered for a moment?
Either way in my time in Squirrels it was absolutely forbidden to leave them rotors running, unlike the 206 where this was done routinely. Can't for the life of me remember why not, but that was the case in my company.