What happened
On 24 May 2001, a Yak-18A, registration RA01370, was conducting a private flight from Lincoln Wickenby airfield to Old Sarum Aerodrome. The pilot, who was flying solo, had recently completed an engine change approximately one month prior to the flight. After refueling at Wickenby, the aircraft departed at 1450 hrs under good weather conditions, despite some haze.
During the flight, the engine experienced an initial intermittent misfire approximately 45 to 50 minutes after departure. Although the pilot initially maintained a cruise of 210 kph and climbed to 3,000 feet as a precaution, subsequent engine irregularities occurred, including further missed beats. During this period, the pilot also discovered that the aircraft's radio was unable to transmit.
As the aircraft approached the destination, the engine began to cough violently and continuously. The pilot decided to continue toward Old Sarum rather than diverting to Boscombe Down. Due to the combination of haze and a high workload, the pilot overshot the airfield and had to perform a turning maneuver to reposition for the runway. At an altitude of approximately 200 feet, about one mile southwest of the runway, the engine ceased functioning entirely. The pilot attempted an emergency landing in a nearby sloping and rough field. The aircraft made a heavy, fast touchdown, rolled, and subsequently overturned onto its back. The pilot sustained minor injuries.
The investigation
The investigation examined the sequence of engine malfunctions and the pilot's decision-making during the emergency. Investigators noted that while the pilot suspected fuel starvation, the wing tanks contained over 120 litres of fuel at the time of the incident, contradicting that theory. The investigation also reviewed the aircraft's recent maintenance history, specifically the engine change performed a month earlier.