What happened
On 27 June 2009, a Taylor JT1 Monoplane, registration G-CEKB, was involved in a fatal accident at Great Oakley Airfield, Essex. The pilot, who was operating the aircraft on a private flight, had initially planned to fly to Old Buckenham Airfield but decided to perform a short circuit to land back at Great Oakley following engine difficulties.
Shortly after departing from Runway 27, the aircraft experienced engine issues. Witnesses observed the aircraft flying at a low altitude, noting an abnormal, loud engine sound. During a tight left-hand manoeuvre intended to return to the airfield, the aircraft rolled heavily to the left, entered a steep nose-down attitude, and stalled. Due to the low altitude, the pilot was unable to recover, and the aircraft impacted the ground near Runway 04. The pilot sustained one fatal injury.
The investigation
Investigators examined the wreckage and the aircraft's engine, a modified Volkswagen 1834 cc unit. The investigation included a review of the pilot's maintenance history and the aircraft's technical configuration. Analysis of the fuel revealed it was not standard Avgas 100LL but rather a mixture containing Mogas, which showed signs of plasticiser contamination from storage.
Engine inspections revealed that the right magneto was producing a weak spark, and the spark plug gaps were found to be significantly below the normal range. Furthermore, the fuel system installation was found to be vulnerable to vapour lock, as unshielded fuel lines were routed alongside the hot engine block, potentially causing fuel to vaporise and interrupt the flow.
Findings
- The aircraft experienced engine-related issues, such as rough running or power loss, almost immediately after takeoff.
- The pilot attempted an abbreviated, low-altitude left-hand circuit to land back at the airfield.
- The aircraft stalled during this manoeuvre, with insufficient height for recovery.
- The use of Mogas and the specific fuel line routing may have contributed to engine performance issues through vapour lock.
- The pilot's maintenance records were incomplete, making it difficult to track the rectification of previous engine problems.