Amateur-built 162F N771SS accident near Gonzales, Texas

Probable cause

failure of the main rotor drive belt for undetermined reasons.

NTSB analysis

The private pilot and his passenger had just departed in a single-engine experimental helicopter when he heard a "loud pop" followed by a loss of engine power. The pilot entered an autorotation from an altitude of 75 feet and flared at approximately 40 feet above the ground to avoid hitting trees. The helicopter landed hard in a grass field and the skids were spread upon impact. The two occupants were able to deplane before the engine exhaust caught the surrounding grass on fire, and subsequently destroyed the helicopter. The pilot reported that the main drive belt, which he had been recently replaced, had failed. The helicopter wreckage was examined by an FAA inspector; however, the drive belt could not be located and it was assumed to have been destroyed in the post-impact fire.

Text from the NTSB. Open the NTSB docket for DFW08CA152 for the full record.