Texas Helicopter Corp OH-13E/M74 N176MR accident near Champaign, Illinois

Probable cause

The pilot’s failure to maintain control of the helicopter during an aerial application maneuver.

NTSB analysis

The pilot of the helicopter reported that he was completing a turn to re-enter a field for an aerial application pass when he heard a loud "pop" and felt a vibration and noted with a decay in rotor speed. He applied aft cyclic and reduced the collective, initiating an autorotation. He stated that the helicopter rolled to the left and that he applied right cyclic with no response. He was able to raise the nose of the helicopter before impacting corn in a 15-degree left bank. The helicopter came to rest 120 degrees from the direction of flight with the engine running. A postaccident examination of the helicopter and a metallurgical examination of the fractured main rotor system components did not reveal any failure or malfunction that would have resulted in the loss of control as described by the pilot.

Text from the NTSB. Open the NTSB docket for CEN13LA436 for the full record.