What happened
On 14 October 2017, a Taylor Titch, registration G-BARN, was performing a private flight at Ripe-Kittyhawk Farm Airfield in Sussex. The pilot, who was experienced on this aircraft type, approached the airfield for a landing at approximately 1400 UTC. Following what appeared to be a standard touchdown, the aircraft's landing gear suddenly collapsed. This caused the aircraft to slide across the airfield surface on its underside for several metres. There were no injuries to the pilot. The impact resulted in damage to the propeller, the lower cowling, and the underside of the aircraft.
The investigation
Investigators examined the aircraft's non-retractable two-piece spring steel undercarriage system. This system is mounted on a wooden plate positioned in front of the main spar and utilizes three steel reinforcing brackets to distribute landing loads. The investigation focused on the centre bracket, which is designed to handle tensile loads, and the outer brackets, which manage compressive loads.
Technical analysis of the failed centre bracket revealed that the welded joints intended to secure the side webs had failed. This failure allowed the webs to open outward, meaning the mounting plate could no longer support the forces of landing, leading to the collapse of the gear blades. Physical examination of the bracket showed poor weld penetration on the outer edges of the side webs where they meet the right-angle section. Additionally, light corrosion was identified on the inner edges of these failed joints.
Findings
- The primary cause of the landing gear collapse was the failure of a welded joint within the centre reinforcing bracket.
- The failure was likely driven by a fatigue process within the weakened welds, following the aircraft's accumulation of 605 landings.
- Poor weld penetration and the presence of light corrosion contributed to the structural weakness of the bracket.