What happened
On 9 June 2008, a Wolf WII Boredom Fighter, registration G-BNAI, was performing a private flight at RNAS Yeovilton, Somerset. The pilot completed the approach to Runway 27, positioned behind a Grob light aircraft, and received clearance for a full stop.
Upon touchdown near the runway threshold, the pilot applied even braking while slightly left of the centreline. As the aircraft taxied toward the exit for the 'Zulu' stand, the pilot disengaged the tailwheel lock to facilitate easier manoeuvring. During this process, the left landing gear suddenly collapsed, causing the left wing to drop and the aircraft to undergo a rapid ground loop to the right. The pilot was able to exit the aircraft safely following the incident, and no injuries were reported.
The investigation
The investigation examined the sequence of events following the landing gear failure and the aircraft's movement during taxi. The aircraft, a single-seat tailwheel biplane, sustained damage to the left leading edge and tip of the lower mainplane, as well as damage to the left landing gear structure. The investigation reviewed the pilot's actions regarding the tailwheel lock and the timing of its disengagement. There was no evidence of any pre-existing damage to the landing gear prior to the event.
Findings
- The aircraft experienced a sudden collapse of the left landing gear during the taxi phase.
- The pilot disengaged the tailwheel lock prematurely while the aircraft was still traveling at a speed higher than recommended for such a manoeuvre.
- The collapse resulted in a significant ground loop and structural damage to the wing and landing gear.