What happened
On 22 August 1999, a DHC-1 Chipmunk 22, registration G-BWJZ, was conducting a local aerobatic flight near Thirsk, North Yorkshire. The flight involved two pilots, with the aircraft owner acting as the handling pilot in the front seat and an experienced aerobatics pilot in the rear.
During the initial takeoff from the downhill grass runway 24, the pilot noticed the left side of the engine cowling was partially open and flapping. Due to the limited runway length, the pilot elected to continue the takeoff rather than aborting, subsequently reducing power once airborne. During the flight, the aircraft performed a low-level left-hand circuit at approximately 50 knots with the first stage of flaps selected.
On final approach, as the pilot attempted to round out at an altitude of roughly 5 to 10 feet, the aircraft entered a stall. The left wing dropped, causing the wingtip to strike the ground with enough force to bend it upwards by 30 degrees. The left main landing gear also impacted the runway, twisting 70 degrees. The momentum caused the aircraft to nose over, resulting in the propeller striking the ground. The pilot in the front seat sustained minor injuries after striking his head on radio switches.
The investigation
The investigation was based on the accident report submitted by the pilot. Investigators examined the sequence of events leading from the takeoff, where the cowling issue was first noted, through to the stall during the landing phase. The investigation also looked into the environmental conditions, noting a north easterly wind of 5 to 10 knots.
Findings
- The aircraft experienced a stall during the round-out phase of the landing.
- The pilot's low approach speed, combined with the influence of a tailwind, was a contributing factor to the stall.
- The aircraft stalled during the round-out phase due to insufficient airspeed.
- The impact resulted in severe damage to the left wingtip, the left main landing gear, and the propeller.