What happened
On 9 June 2007, a Pioneer 300, registration G-CEEG, was conducting a private flight from a private airstrip to Bute. During the pre-landing checks at Oban Airport, the pilot selected full flaps, which triggered a red warning light and an audible buzzer, indicating the landing gear was not locked in the down position. The circuit breaker (CB3) had tripped.
After attempting to reset the circuit breaker six times, the pilot observed a brief blue flashing light but was unable to use the emergency manual crank to lower the gear, as the handle would not move. Through the cockpit inspection window, the nose gear appeared to be down. Upon landing, the right main landing gear partially collapsed while the aircraft was still moving forward, followed by the collapse of the nose landing gear. This caused the propeller to strike the runway, resulting in a broken propeller, damage to the engine cowling, and buckled landing gear jacks.
The investigation
Investigators examined the electrically operated, retractable tricycle landing gear system. They found that the right main landing gear screw jack and the nose leg locking rod had buckled. Upon removing the right leg from the retraction spindle, investigators discovered paint on the inner portion of the spindle and noted a lack of sufficient grease on the painted area.
Further inspection revealed that the aircraft had been painted approximately 86 flying hours prior to the accident. The importer confirmed that the landing gear legs were fitted to the spindles before the spray painting process occurred. While the owner had greased the components 20 hours before the flight, the presence of paint debris on the spindle was identified as a factor in the mechanical seizure.
Findings
- The right main landing gear screw jack and nose leg locking rod had buckled.
- Paint debris on the right landing gear retraction spindle contributed to the leg seizing.
- The presence of paint on the spindle prevented adequate lubrication of the bearing face.
- The pilot attempted to reset the circuit breaker multiple times in flight.
Safety action
- Safety Recommendation 2007-113: It is recommended that the Civil Aviation Authority take appropriate action to increase awareness within General Aviation communities regarding the risks associated with resetting circuit breakers during flight.