Aerospatiale SA315 N17285 accident near Winters, California

Probable cause

A loss of engine power for reasons that could not be determined because postaccident examination of the airframe and engine did not reveal any anomalies that would have precluded normal operation.

NTSB analysis

The pilot reported that, after takeoff and about 200 feet above ground level, the engine decelerated to an idle power setting. The pilot initiated an autorotation, but, due to the low height above the ground, the helicopter landed hard. During the postaccident engine examination, the fuel pump and fuel governor were removed and placed on a test bench for an operational check. Both the fuel pump and governor performed within normal parameters. Further examination found non-metallic particles within the fuel filter; however, their presence would not have reduced the fuel flow and contributed to the engine deceleration event. An examination of the remaining engine components and airframe systems revealed no mechanical failures or malfunctions that would preclude normal operation. The reason for the loss of engine power could not be determined.

Text from the NTSB. Open the NTSB docket for WPR10LA452 for the full record.