WPR12LA107

A flight control malfunction while maneuvering for reasons that could not be determined because postaccident examination revealed no evidence of a mechanical malfunction or failure that would have precluded normal operation.

The pilot reported that he was conducting flybys to film a segment for a documentary. During his last run, he initiated a 150- to 180-degree climbing right turn to about 200 ft above the ground. After the turn, he attempted to neutralize the flight controls in preparation for a normal approach to land, but he was unable to move them. The helicopter remained in the same turn rate with the same collective pitch and cyclic input until ground impact. A postaccident examination of the helicopter revealed no evidence of preimpact mechanical malfunctions or failures that would have precluded normal operation. The reason for the flight control malfunction could not be determined.

On March 01, 2012, at 1220 mountain standard time, N197LE, an experimental exhibition Bell AH-1F helicopter experienced a loss of directional control during maneuvering flight and impacted the ground at Coolidge Municipal Airport (P08), Coolidge, Arizona. The helicopter was operated by the Army Aviation Heritage Foundation and Museum, Inc., under the provisions of 14 Code of Federal Regulations (CFR) Part 91. The pilot and mechanic received minor injuries; the helicopter sustained substantial damage. Visual meteorological conditions prevailed for the local area flight that departed P08 at an undetermined time. The pilot stated that the purpose of the flight was to film a segment for a documentary. The first flight of the filming sequence was uneventful. It lasted approximately 10 minutes and included helicopter flybys. The next filming sequence consisted of the accident helicopter and a vehicle in a race simulation. At 1205, a practice run began that terminated at the start/finish line. After crossing the finish line, the pilot initiated a climbing 150- to 180-degree right turn to an altitude of about 200 feet above the ground. He attempted to neutralize the controls in preparation for a normal approach for landing but was unable to move them. The helicopter remained in the same rate of turn, with the same collective pitch and cyclic input, until impact with the ground. The pilot further stated that, at impact, he tried to activate the emergency hydraulic switch. A postaccident examination by the Federal Aviation Administration airworthiness inspector revealed no mechanical failures or malfunctions that would have precluded normal operation. Neither the pilot nor the operator provided a completed NTSB Pilot/Operator Aircraft Accident ReportForm 6120.1.