What happened
On 23 August 2012, a Fournier RF4D, registration G-AVKD, was conducting a private flight at Lasham Airfield, Hampshire. The aircraft landed normally on the grass runway; however, during the subsequent ground roll, the landing gear collapsed. This failure caused the propeller to strike the ground, resulting in damage to the propeller.
No injuries were reported following the incident, and the pilot was the sole occupant of the aircraft.
The investigation
Investigators examined the aircraft's landing gear mechanism and the cockpit warning systems. The aircraft's landing gear warning horn is designed to activate if the airbrakes are deployed while the gear is not in the locked-down position. During the investigation, it was noted that the pilot had performed a pre-flight test of the gear, which had been satisfactory. Before the landing in question, the pilot operated the landing gear latch lever to lower the gear, which locked the single main wheel in the down position.
During the approach, the pilot briefly deployed the airbrakes. The pilot reported that the landing gear warning horn did not sound during this maneuver, despite the gear potentially being in an unsafe state. Following the accident, the aircraft was lifted to allow for a manual inspection of the gear, which was then lowered and locked to facilitate movement to a hangar.
Findings
- The investigation established that the landing gear latch lever, which is not visible from the cockpit during flight, may have been worn.
- This wear potentially prevented the main wheel from being fully locked in the down position.
- The landing gear warning horn failed to alert the pilot to the unsafe gear configuration when the airbrakes were utilized during the approach.