What happened
On the evening of November 8, 2002, a Cessna 303 Crusader, registered F-GDFP, was performing a training flight at Nîmes Garons Airport. Following a landing under normal meteorological conditions, the pilot heard the "gear unsafe" warning at approximately 30 knots. Simultaneously, the green light for the left main landing gear extinguished, and the pilot felt the aircraft begin to tilt to the left.
The pilot successfully taxied the aircraft onto a runway exit, but the left side of the plane continued to sink. The crew shut down the engines and evacuated the aircraft. The collapse continued until the wing and propeller made contact with the ground.
The investigation
Investigators examined the wreckage of the left main landing gear and discovered that the rear pivot axis had shifted forward out of its bearing in the airframe, causing the gear assembly to move backward and upward. While the safety wire was present but broken, the locking pin intended to secure the pivot axis was missing.
Further inspection of the forward attachment of the left main gear revealed that the pin in use was non-compliant with manufacturer specifications. The installed pin had a diameter of 4.32 mm and an opening of 1.49 mm, whereas the manufacturer's recommended pins require a 5.05 mm diameter and a 0.85 mm opening.
Records indicated that the aircraft had been involved in a significant accident several years prior, which had caused extensive damage to the left wing and left main landing gear. While maintenance had been performed on the left gear since those repairs, no recent work had been performed specifically on this attachment point. The investigation also noted that the safety wire functioned only as a visual indicator of the pin's presence and was not designed to hold the pin in place.
Findings
- The primary cause of the gear collapse was the use of a non-compliant pin at the forward attachment of the left main landing gear.
- The incorrect dimensions of the pin allowed the rear pivot axis to displace, leading to the structural failure of the gear assembly.
- The aircraft's left main gear had undergone significant repairs following a previous accident, though no recent maintenance was recorded for this specific component.