What happened
On 23 April 1999, an Extra 300/L, registration G-XTRS, was conducting a private flight from Inverness to Kemble. While flying in formation with a Cessna 177RG near Wigan, the pilot determined that deteriorating weather conditions made continuing under Visual Flight Rules (VFR) unsafe. Consequently, the crew decided to divert to Liverpool Airport.
Upon approaching Liverpool, the pilot accepted an instruction for a right-hand base approach to Runway 27. As the aircraft followed the lead Cessna, the pilot noted the onset of light rain. During the final stages of the approach, the pilot reduced power at approximately 100 feet to establish a three-point landing attitude. During the flare, the stall warning activated at 70 knots. The pilot, who was monitoring altitude via peripheral vision due to limited forward visibility, experienced a heavy impact as the main gear contacted the runway.
Following a loud impact, the aircraft swerved 45 degrees to the left, causing the left wingtip to dip. Despite corrective rudder and braking inputs, the aircraft veered toward the runway edge, where the main landing gear collapsed. The fuselage struck the ground, and the propeller sustained significant damage. Both the pilot and the passenger escaped the aircraft without injury.
The investigation
The investigation involved a review of the pilot's report and a technical examination of the fractured landing gear leg. The aircraft's main gear is a single-member composite structure consisting of two halves joined by an adhesive bond, featuring a foam core and fiberglass reinforcement.
Investigators compared the failed component against the manufacturer's original design specifications. The examination revealed that the structural failure originated within the adhesive bond that holds the two halves of the gear leg together. This bond is the critical element responsible for distributing loads across the structure.
Findings
- The left main landing gear leg failed, causing the subsequent runway excursion.
- The failure was caused by a breakdown in the adhesive bonding between the two halves of the composite gear member.
- The pilot may have been distracted by unfamiliar runway touchdown zone lighting, which potentially led to an inaccurate perception of height and a heavy landing.