NTSB Factual Report

While en route to his planned destination, the pilot noticed that one of two latches on the right side cabin door had come loose. He therefore elected to land in a grassy area alongside the runway of a nearby airstrip. While turning from base to final, the cyclic was momentarily restricted by being caught on the shorts of the passenger. Although the movement of the cyclic was only momentarily restricted, it resulted in the pilot delaying his transition to a slower airspeed and a reduced rate of descent prior to establishing a pre-landing hover. Instead of executing a go-around, the pilot decided to continue his transition, but he was unable to enter a hover prior to touching down with a slight forward movement on the rough uneven terrain. When the helicopter touched down, the left skid became stuck in a rut, and that, along with a slight tailwind and the residual forward movement of the helicopter, resulted in a dynamic rollover. In his written statement, the pilot said, "Making a go-around would have been the best way to prevent this accident."

NTSB Probable Cause

The pilot's failure to execute a go-around and his failure to reduce his groundspeed to zero prior to touching down on the rough/uneven terrain. Factors include the momentary restriction of a flight control, rough/uneven terrain, and a tailwind.