What happened
On 14 September 2018, an RAF 2000 GTX-SE gyroplane, registration G-BXDE, was being operated for a private flight at North Weald Airfield in Essex. The flight was intended to revalidate the pilot's gyroplane rating, with an examiner on board to observe the procedure.
During the takeoff roll on Runway 20, the aircraft's performance deviated from normal parameters. While the pilot expected liftoff at 40 mph, the airspeed reached 70 mph while the aircraft was still on the ground. The examiner noted that the rotor speed was only 150 rpm, significantly lower than the expected range. The aircraft then abruptly became airborne, rolling to the right and completing a 180-degree turn before descending. The aircraft struck the ground on its right side on the grass adjacent to the runway, eventually coming to rest on a parallel taxiway.
The accident resulted in one serious and one minor injury. The examiner sustained three broken vertebrae and various lacerations, while the pilot escaped with minor injuries.
The investigation
The AAIB examined the aircraft and the circumstances surrounding the takeoff. The investigation focused on the management of rotor speed and airspeed, as well as the physical state of the flight controls.
Investigators noted that the rotor brake was found to be very stiff during pre-flight checks, requiring significant effort to release. While the pilot believed the gust lock had been disengaged upon boarding, the examiner suggested the lock might have been inadvertently re-engaged during the struggle to release the rotor brake. Although the gust lock was found disengaged after the crash, it may have been released during the impact sequence. Furthermore, the investigation looked into whether the presence of another aircraft at the holding point created pressure to expedite the departure.
Findings
- The takeoff was characterized by insufficient rotor speed and excessive airspeed.
- The pilot did not perform a full and free movement check of the flight controls immediately prior to the takeoff roll.
- The pilot may have been distracted by the difficulty in releasing the rotor brake, potentially leading to the gust lock being left engaged.
- The presence of a following aircraft may have created subconscious pressure to depart quickly.
- The examiner was focused on observing the pilot's performance and was not prepared to intervene when the takeoff parameters became abnormal.