CEN24LA013

The pilot reported that, while on the downwind leg of the traffic pattern, he was distracted while looking for other traffic in the pattern when he noticed that his airspeed had decayed to 37 mph, below the aircraft flight manual’s recommended traffic pattern airspeed of 65 mph. The pilot attempted to correct by increasing engine throttle but subsequently lost control. The gyroplane impacted terrain while in the left downwind leg, which resulted in substantial damage to the main rotor system and empennage. Postaccident examination of the gyroplane revealed no preaccident mechanical failures or malfunctions that would have precluded normal operation. Based on the available information, the pilot likely unloaded the rotor blades inadvertently, known as buntover, when he applied engine throttle to correct for the decaying airspeed. The sudden throttle application caused the gyroplane to abruptly pitch forward and tumble. The FAA Rotorcraft Flying Handbook notes that, in most cases, the proper recovery procedure for the condition is to immediately remove power and load the rotor blades.

On October 16, 2023, about 1130 central daylight time, a Magni M24 gyroplane, N90HM, was substantially damaged when it was involved in an accident near Mount Sterling, Illinois. The pilot was not injured. The gyroplane was operated as a Title 14 Code of Federal Regulations (CFR) Part 91 personal flight. The pilot reported that the gyroplane was on downwind for runway 36 at the Mount Sterling Municipal Airport (I63), when he noticed that his airspeed had decayed to 37 mph, below the recommended traffic pattern airspeed of 65 mph. He reported that his airspeed had decayed while his attention was diverted looking for other traffic. The pilot attempted to correct by increasing engine throttle but subsequently lost control. The gyroplane impacted terrain in the left downwind, which resulted in substantial damage to the main rotor system and empennage. During the recovery of the gyroplane, the smell of automotive fuel was present with soil discoloration around the area of the fuel cap. Postaccident examination revealed no preaccident mechanical failures or malfunctions with the gyroplane that would have precluded normal operation. The engine was successfully operated during the examination. The rotor pitch trim actuator arm was observed to be 2 inches from the actuator, which corresponds to a pitch trim setting of about 65 mph. The gyroplane flight manual recommends an airspeed of 65 mph during the traffic pattern when preparing to land. The FAA Rotorcraft Flying Handbook (FAA-H-8083-21), Section 21-3, states that, “If rotor force is rapidly removed, some gyroplanes have a tendency to pitch forward abruptly. This is often referred to as a forward tumble, buntover, or power pushover.” Referring to the recovery procedure, it notes that, “In most cases, you need to remove power and load the rotor blades.”