What happened
On 15 May 2003, a Maule M5-235C Lunar Rocket, registration G-CCBF, was returning to Leicester Airport from Fenland Aerodrome. During the approach, the crew observed a vertical column of smoke, suggesting light wind conditions. The aircraft performed a standard three-point touchdown on Runway 10 and continued straight for roughly 200 metres. As the groundspeed dropped to approximately 12 knots, the aircraft experienced a sudden lurch and began a rightward turn. In an attempt to correct the direction, the pilot applied left differential braking, which instead triggered a violent swing to the left. This maneuver caused the right landing gear to collapse inward under the fuselage. The aircraft eventually came to a halt with its right wingtip touching the ground, having rotated 15 to 0 degrees from its original heading. There were no injuries to the two occupants, though the aircraft sustained damage to the propeller, the main spar, and the right undercarriage.
The investigation
The investigation focused on the cause of the sudden turn and the subsequent gear collapse. Investigators examined the aircraft's tailwheel assembly, which features a steerable mechanism linked to the rudder that can be disconnected to allow castoring. While previous incidents had been linked to failures in this locking mechanism, a post-accident inspection of G-CCBF confirmed the assembly was functioning correctly and showed no defects.
Findings
- A light breeze had developed by the time of the incident, which was recorded at 5 knots from 130° shortly after the accident.
- The pilot was caught by a crosswind component during the low-speed phase of the landing roll.
- The use of differential braking significantly worsened the aircraft's directional instability, leading to the structural failure of the landing gear.