What happened
On 2 March 2018, a RAF 2000 GTX FI gyrocopter, registration ZU-RLK, was conducting a private flight from a farm in the Alldays area toward a landing strip near Vivo, Limpopo. Roughly ten minutes into the flight, the pilot observed that the digital engine and rotor tachometers had gone blank, leading to the assumption of an electrical failure.
In response to this perceived failure, the pilot attempted a precautionary landing on a nearby gravel road. During the final approach, at an altitude of approximately 50 ft, the aircraft entered a sudden and rapid descent. Despite the pilot applying full engine power, the aircraft struck the road surface with significant force. The gyrocopter skidded 60 meters before rolling onto its right side, resulting in substantial damage to the aircraft. The pilot sustained minor injuries.
The investigation
An investigation by the SACAA AIID examined the circumstances surrounding the electrical failure and the subsequent flight profile. While the aircraft's airspeed indicator remained functional because it was mechanically driven via a pitot tube, all other instruments were digital and lost power during the event. The investigation could not definitively identify the specific cause of the electrical failure.
Investigators also reviewed the aerodynamic characteristics of the aircraft type. It was noted that gyrocopters are susceptible to high rates of descent when flown at low forward airspeeds. The investigation highlighted that even with full power applied, a failure to maintain minimum level flight speed can result in a continuous descent.
Findings
- The primary factor in the accident was an unsuccessful forced landing characterized by a high rate of descent.
- The pilot's aeronautical decision-making was noted as impulsive, as a more rigorous fault-finding process could have been utilized to verify the extent of the electrical issue before committing to the landing.
- The pilot relied on the loss of digital tachometers as evidence of electrical failure without using the voltmeter as a secondary reference.
Safety action
- Pilots of gyrocopters are reminded of the inherent dangers associated with very low forward airspeeds.
- It is emphasized that pilots must strictly adhere to pilot operating handbooks regarding slow flight and maintain minimum safe altitudes above the ground.
- Training should place greater emphasis on emergency fault-finding, rectification procedures, and improved aeronautical decision-making.