What happened
On 1 December 2009, a YAK-52, registration G-IMIC, was conducting a private flight near the Yarmouth area. While approaching Seething Airfield in Norfolk, the pilot observed another aircraft backtracking on Runway 24. To maintain visual separation, the pilot lowered the aircraft's nose to monitor the other aircraft's position. During this period, a minor malfunction involving the flap operating light occurred.
As the pilot prepared for landing, the combination of monitoring the runway traffic and the flickering flap light resulted in the pilot failing to extend the landing gear. The aircraft touched down with the wheels still retracted, causing damage to the propeller, lower cowling, wingstep, and tailskid. The pilot, who sustained no injuries, vacated the aircraft without incident.
The investigation
The AAIB investigation examined the sequence of events and reviewed historical data regarding similar incidents. The investigators noted a disproportionate frequency of wheels-up landings involving YAK-50 and YAK-52 aircraft in the UK compared to other single-engine types with retractable gear. A review of CAA records between 1995 and the accident showed 22 such incidents involving YAK aircraft, many of which were attributed to human factors.
Investigators also looked into the potential for 'gear not down' warning systems. While such systems can reduce the rate of these incidents, they are not standard on most UK-registered YAK aircraft. The investigation found that while insurance companies were incentivizing the installation of these modifications, the CAA determined that the landing gear design mitigated the overall risk, meaning no mandatory airworthiness directives were required.
Findings
- The pilot's attention was diverted by the presence of another aircraft on the runway.
- A minor malfunction of the flap operating light further distracted the pilot during the final landing configuration.
- The pilot failed to extend the landing gear due to these combined distractions.