Interesting and not terribly comforting thought. . .. .I'm not an expert in POF, but had one or two interesting moments teaching autos in Robbos, including an instance of having to get the Nr needle back from 82%.. .. .My thoughts: Bare in mind that 1000fpm is only 10knots. (1800fpm in auto is only 18knots, but doesnt seem that slow at 40feet!). If you are that light, I would imagine the aircraft would stop climbing very quickly (low upward momentum) if it went deathly quiet from behind. But like you say, I'm not convinced it would be quickly enough.. .. .Yes the Nr would drop like a stone, hence lever down to around your ankles and then flare like hell. In the flare the air flow will have a large component through the rotor disc from below so in theory at least you could get some autorotative force going on whilst still climbing. That all assumes that you are climbing with an IAS of 60knots as per the flight manual. Hopefully though, you would end up with a sustainable Nr, with albeit a very low IAS. Providing you have some of that altitude stuff you should get down safely.. .. .Another reason for a large flare would be to keep the disc loaded. Otherwise a tail might get docked.. .. .Those are my thoughts, what does anyone else think? I am not going to try to prove my theory! Something about old and bold! So may be there is something to be said for keeping a low ROC.