Incident Overview
A helicopter engaged in a sightseeing flight encountered a loss of engine power while approaching to land. The pilot performed an autorotation, touching down 70 feet short of the designated helipad. During the touchdown, the main rotor blades struck the tail boom, severing it.
Pilot Statement
The pilot reported that after touchdown, the engine continued to operate at idle speed. The pilot also stated that he did not use carburetor heat before or after the loss of engine power.
Post-Accident Engine Tests
Following the accident, the engine was subjected to tests at a power setting higher than that selected by the pilot at the time of the power loss. These tests revealed no evidence of mechanical failure or malfunction that existed before the crash.
Carburetor Icing Conditions
A review of the carburetor icing probability chart indicated that the flight was conducted under conditions conducive to serious carburetor icing at glide power and visible carburetor icing at rated power. The pilot did not use carburetor heat during the flight.