Accident Summary
On July 24, 2013, at approximately 1130 central daylight time, a Texas Helicopter OH-13E, registration N176MR, collided with terrain near Champaign, Illinois. The helicopter was engaged in an aerial application flight under 14 Code of Federal Regulations Part 137, operated by Reynolds Aerial Service LLC. Visual flight rules prevailed, and the flight was not on a flight plan. The local flight had originated about 1120. The airline transport pilot was not injured, and the helicopter received substantial damage to the airframe.
Pilot Report
The pilot reported that while completing a turn to re-enter a field for an aerial application pass, he heard a loud "pop" and experienced a "1 to 1" vibration along with a decay in rotor speed. He applied aft cyclic and reduced the collective, initiating an autorotation. The helicopter rolled to the left, and when the pilot applied right cyclic there was no response. He was able to raise the nose of the helicopter prior to impacting the corn in a 15-degree left bank. The helicopter came to rest 120 degrees from the direction of flight. The pilot stated that the engine was running when the helicopter came to rest.
Examination Findings
The helicopter was relocated to Scott's Helicopters in LeSueur, Minnesota, where it was examined by the National Transportation Safety Board (NTSB). The upper pitch change link, the equalizer beam rod end, the lower pitch change link, and the lateral cyclic torque tube assembly were found fractured. These components were removed for further examination by the NTSB metallurgical laboratory. The examination revealed that the fractures were a result of overstress with no evidence of any preexisting cracks. The examination of the helicopter did not reveal any failure or malfunction that would have resulted in the loss of control as described by the pilot.