What happened
On 7 July 2002, a Yak-50, registration RA44549, was conducting a private flight at Compton Abbas Airfield in Wiltshire. While flying the downwind leg of the circuit, the pilot attempted to extend the landing gear. The pilot believed the landing gear selector lever had been moved to the down position and that the locking slide had been engaged. Due to concentration on other traffic within the circuit, the pilot could not confirm if the green landing gear indicators had illuminated.
During the final approach, the pilot performed a visual check of the lever position and noted that the locking bar appeared to be correctly engaged. However, the aircraft subsequently touched down with the landing gear still in the retracted position. The impact resulted in damage to the propeller, cowling, and engine shockloading, though there were no injuries to the pilot.
The investigation
Investigators examined the aircraft's landing gear system following the incident. An engineering inspection determined that the landing gear system was fully serviceable and functioning as intended.
Further flight testing was conducted to replicate the circumstances of the accident. The testing established that it was technically possible to move the landing gear lever to a position where the locking slide could be engaged without actually activating the gear lowering system. However, the investigation noted that achieving this specific configuration was extremely difficult.