Interesting 180 Autorotation accident. The National Transportation Safety Board determines the probable cause(s) of this accident in pilot's failure to maintain adequate main rotor rpm during an autorotation, which resulted in a hard landing.
180 degree turn autorotation in a R22 Beta2 with text commentry on what the pilot is doing and looking for during the trip down.
Clip from a helicopter instructional video - AUTOROTATION - How to land a helicopter in the event of a power failure. Excellent video, very useful and informative. Talks you through the manoeuvre in detail and shows it from inside and outside the Robinson R22. Very nice!