ATL97LA067

The certified flight instructor (CFI) was demonstrating a 180 degree turn autorotation with a power recovery. The CFI entered the maneuver approximately 600 feet above the ground. About 3/4 through the 180 degree turn, he noticed that the rotor speed was low. When the CFI decided to return the throttle to full power, there was no engine response. The CFI continued the approach, which resulted in a hard landing on the heel of the left skid, and the helicopter rolling over. Examination of the helicopter failed to disclose a mechanical problem or a system malfunction. During a functional check of the engine, it operated between idle and a moderated power range. Examination of the airframe disclosed that the skids were spread, and the landing gear damper assembly was fractured. According to FAA Advisory Circular, AC 61-13A, during the flare phase of an autorotation, the cyclic control should be moved forward to level the helicopter in preparation for landing. The advisory circular also stated that 'if a landing is to be made, allow the helicopter to descend vertically. Apply collective pitch smoothly to check the descent and cushion the landing.'

On May 1, 1997, at 1700 eastern daylight time, a Hughes 269A helicopter, N37754, collided with the ground during an emergency landing after the engine quit at the Lake Wales Municipal Airport in Lake Wales, Florida. The training flight operated under the provisions of Title 14 CFR Part 91 with no flight plan filed. Visual weather conditions prevailed at the time of the accident. The helicopter sustained substantial damage. The dual student and the certified flight instructor were not injured. The flight departed from Lake Wales, Florida, at 1650.

The dual student stated that he was enrolled in a certificated pilot school, Sunrise Aviation, and was receiving flight training under the approved helicopter training program. During the accident training session, the flight instructor was demonstrating a 180 autorotation with a power recovery. The certified flight instructor entered the maneuver approximately 600 feet above the ground. The certified flight instructor initiated the procedure by rolling the throttle to idle and entered the simulated power off procedure. As he maneuvered the helicopter through the procedure, the engine quit. Approximately 3/4 through the 180 degree turn the certified flight instructor noticed a low rotor rpm condition. When the certified flight instructor decided to return the throttle to full power, there was no response or power increase from the engine. The certified flight instructor continued the approach and reported that the helicopter landed hard on the left heel of the left skid and rolled over.

The examination of the helicopter failed to disclose a mechanical problem or a system malfunction. During the functional examination, the engine operated between idle and the moderated power range (see attached FAA Inspector's Statement). The airframe examination disclosed that the skids were spread and the landing gear damper assembly was fractured.

According to FAA Advisory Circular, AC61-13A, during the flare phase of the autorotation, the cyclic control should be moved forward to level the helicopter in preparation for landing. The advisory circular also states that "if a landing is to be made, allow the helicopter to descend vertically. Apply collective pitch smoothly to check the descent and cushion the landing." The advisory circular also advises the pilot to avoid landing on the heels of the skid. (see attached excerpts from Advisory Circular AC 61-13A).