What happened
On 31 August 2007, a private flight involving a Yakovlev Yak 52, registration ZU-CWJ, was returning to Margate Aerodrome. After departing from the same airfield, the pilot was cleared by air traffic control to land on runway 04. During the approach, the pilot opted to execute a flapless landing at an indicated airspeed of 65 knots. Upon touchdown, the aircraft experienced a sudden sink rate while maintaining a high nose-up attitude. It was at this moment that the pilot discovered the landing gear had not been deployed.
Both the pilot and the passenger escaped the incident without injury, though the aircraft suffered minor damage to its wooden propeller and landing gear.
The investigation
The investigation focused on the pilot's actions regarding the aircraft's control systems and the sequence of gear selection. Interviews revealed a critical misunderstanding of the cockpit instrumentation. On this specific aircraft, the lighting logic for the flaps is the inverse of the landing gear system. Specifically, a green light indicates that the flaps are in the up position, whereas a green light for the landing gear signifies that the gear is down and locked.
Investigators established that the pilot had inadvertently moved the landing gear lever to the neutral position rather than the down position. During this process, the pilot observed a green light on the instrument panel and mistakenly interpreted it as a confirmation of the gear being locked, when in fact, the light corresponded to the flap configuration.
Findings
- The pilot failed to properly select the landing gear in the down position, leaving it in the neutral position.
- A significant contributing factor was the conflicting visual logic between the landing gear and flap indication lights, which led the pilot to misinterpret a green light as a signal that the gear was locked.
- The pilot's decision to perform a flapless landing contributed to the specific flight dynamics during the touchdown.