Hughes OH 6A N6186U accident near Preston, Georgia

Probable cause

A partial loss of engine power for reasons that could not be determined based on the available information.

NTSB analysis

During the flight to observe feral swine invading farm fields, the pilot noted a loss of engine power and rotor rpm. He maneuvered the helicopter away from trees for an autorotation to an open, plowed cornfield. During the landing on rough terrain, the helicopter nosed forward and the main rotor blades contacted the ground, resulting in substantial damage to the helicopter.

A postaccident examination of the flight controls, drive train, fuel system, main rotor system, and tail rotor system did not reveal evidence of a preexisting mechanical malfunction or anomaly. The engine was removed and placed on a test stand; it ran normally for about 2 minutes before the run was concluded. A laboratory test of a fuel sample was unremarkable. The reason for the loss of engine power could not be determined.

Text from the NTSB. Open the NTSB docket for ERA20LA071 for the full record.