Ketchikan, AK, USA
N779DZ
ROBINSON HELICOPTER COMPANY R44 II
The helicopter pilot reported that during the engine start sequence on an offshore barge with a bare steel deck, the main rotor system clutch was engaging, and the throttle was applied to maintain 60 percent engine revolutions per minute. He reported that the skid and tundra/snow board equipped helicopter began a rapid right yaw, left pedal was applied simultaneously with throttle closure, but the helicopter rapidly yawed left resulting in the vertical stabilizer and tail rotor blade system impacting a crane stationed on the deck. The pilot then shut down the helicopter without further incident. A postflight inspection revealed substantial damage to the vertical stabilizer and the tail rotor blade system. The pilot reported there were no pre-impact mechanical failures or malfunctions with the airframe or engine that would have precluded normal operation.
The helicopter pilot reported that during the engine start sequence on an offshore barge with a bare steel deck, the main rotor system clutch was engaging, and the throttle was applied to maintain 60 percent engine revolutions per minute. He reported that the skid and tundra/snow board equipped helicopter began a rapid right yaw, left pedal was applied simultaneously with throttle closure, but the helicopter rapidly yawed left resulting in the vertical stabilizer and tail rotor blade system impacting a crane stationed on the deck. The pilot then shut down the helicopter without further incident. A postflight inspection revealed substantial damage to the vertical stabilizer and the tail rotor blade system. The pilot reported there were no pre-impact mechanical failures or malfunctions with the airframe or engine that would have precluded normal operation. The operator reported as a safety recommendation, "One other factor that needs to be discussed is mission oriented versus safety oriented. This was nearly the last flight of this project and although it was discussed that this helicopter was being operated on the steel deck of the barge, it is industry standard to have non-skid matting for the helicopter to land on. The pilot elected to disregard the bother of having some sort of non-skid matting. Mission oriented became more important than safety oriented." AIRCRAFT INFORMATION The skids were equipped with tundra/snow boards, which were installed under a Federal Aviation Administration supplemental type certificate. ADDITIONAL INFORMATION Robinson Helicopter Company R44 II Pilot's Operating Handbook The Robinson Helicopter Company R44 II pilot's operating handbook lists the engine start and run-up procedures. A caution for starting the engine and run-up states; On slippery surfaces, be prepared to counter nose-right rotation with left pedal as governor increases revolutions per minute.
The pilot's failure to maintain directional control during the engine start sequence, which resulted in the helicopter sliding on a steel deck and impacting a crane. Contributing to the accident was the absence of traction material on the helicopter operations portion of the steel deck.
Source: NTSB Aviation Accident Database
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