Accident Overview
On 12 September 2009 at 1440 UTC, a Grob G115E Tutor, registration G-BYWH, experienced structural failure of its landing gear support during rollout after a stream landing at RAF Leeming, North Yorkshire. The aircraft, operated by the Northumbrian University Air Squadron, was the third in a three-aircraft formation. The flight was part of the station's families' day flying programme.
Flight History
The formation performed a flypast and then conducted a Visual Run In And Break for a stream landing on Runway 16. The commander of G-BYWH, occupying the No 3 position, maintained a higher approach speed (80 kt) to mitigate wake turbulence, with a steeper approach. He elected to land to the left of the centreline. Both crew and passenger reported touching down just beyond the arrestor cable at a speed slightly faster than normal.
During rollout, the pilot of G-BYWH perceived a rapid closure rate with the No 2 aircraft. Both occupants simultaneously applied full brake pressure. The aircraft began to skid, with nosewheel shimmy and mainwheel brake judder reported. Two loud cracks were heard, followed by a loss of stopping performance. The aircraft came to a halt alongside the other two aircraft with approximately 2 ft wingtip separation.
Damage and Inspection
Post-flight inspection revealed damage to the landing gear rib and lower wing skin. The landing gear support structure had failed in overload. Subsequent analysis identified possible manufacturing issues that may have contributed to the failure.
Personnel and Planning
The three aircraft commanders were Qualified Flying Instructors with over 3,000 hours experience. The passenger in G-BYWH was a qualified instructor on type but had not been involved in planning. The formation lead did not calculate landing distance but relied on experience; the calculated landing distance with a 10 kt tailwind was 2,200 ft, further increased by the higher touchdown speed of the No 2 and No 3 aircraft.
Investigation
The accident was investigated by the AAIB and an RAF Unit Inquiry. Five safety recommendations were made.