What happened
On 1 June 2006, an RAF 2000 gyroplane, registration G-REBA, was being flown on a private mission toward Bodmin Airfield. The pilot, who was also the aircraft owner, departed from Watchford Farm and initially maintained a steady flight path. Witnesses on the ground observed the aircraft flying at an altitude between 300 and 500 feet.
During the flight, the aircraft's behavior changed significantly. While the pilot had previously reported no difficulties to air traffic services, onlookers noted the aircraft appeared to be caught in a crosswind. Suddenly, the main rotor blades converged above the aircraft, causing the engine to cut out. The gyroplane subsequently entered a near-vertical descent, striking the ground west of Colliford Lake. The impact resulted in one fatality.
The investigation
Investigators examined the wreckage and recovered a GPS unit and a PDA containing track logs. The data revealed that the aircraft's speed fluctuated significantly in the moments before the crash, moving from approximately 83 mph down to 31 mph.
Technical analysis of the wreckage showed that the main rotor blades had struck the tail assembly, specifically the fin and rudder. This contact caused the propeller blades to break away from the hub and the drive belt to fail. The investigation also looked into the pilot's health, noting that a post-mortem revealed severe coronary artery disease. Additionally, the investigators examined the aircraft's control system, noting that the owner had recently performed maintenance and modifications to the control components following a previous incident.
Findings
- The investigation could not definitively establish a single cause, but identified three possibilities: pilot medical incapacitation, a pilot-induced 'power pushover' maneuver, or a structural/control system failure.
- The aircraft was susceptible to a 'power pushover'—a nose-down pitching motion caused by propeller thrust acting above the center of gravity, which can lead to the rotor blades striking the tail.
- The pilot had an undiagnosed medical condition that could have led to sudden incapacitation.
- The aircraft was flying at speeds where longitudinal instability is a known characteristic of this model.
Safety action
- The CAA issued Mandatory Permit Directive MPD 2006-013, which restricted the operation of this aircraft type, including a reduced maximum speed and requirements for removing doors during flight.