What happened
On 3 October 1999, a YAK 52, registration LY-AKF, was performing a private flight at Dunkeswell Airfield in Devon. Following a routine landing, the aircraft was still traveling along the runway when the pilot attempted to retract the flaps. However, the pilot mistakenly operated the landing gear lever instead. This error caused the aircraft to settle onto the ground on its left wing. During the sequence, the propeller made contact with the runway surface before the engine could be shut down.
There were no injuries to the pilot, though the aircraft sustained substantial damage, including a shock-loaded engine, damage to the propeller, flaps, nosewheel, and tail skid.
The investigation
The investigation focused on the cockpit ergonomics and the sequence of events following the landing. It was established that the aircraft's control layout features levers with similar shapes and mechanical operations for both the flaps and the landing gear. Both controls are operated using the left hand. The landing gear lever is positioned on the instrument panel in front of the throttle and utilizes an up-and-down motion, whereas the flap lever is situated behind the throttle and operates with a fore-and-aft motion.
Findings
- The primary cause of the accident was the inadvertent retraction of the landing gear due to the pilot selecting the incorrect lever.
- The cockpit design of the YAK 52 presents a high risk of error because the flap and gear levers are similarly shaped and located in close proximity.
- Previous attempts by UK importers to modify the aircraft to prevent such mistakes have been documented, but no universal solution has been successfully implemented to eliminate the risk of accidental gear retraction.