What happened
On 10 August 2008, a Europa XS, registration G-CHOX, was performing a private flight departing from Sherburn-in-Elmet. While climbing through approximately 2,000 ft, the passenger noticed a burning smell, which was immediately followed by smoke appearing in the cockpit. Although the crew checked the electrical systems, no faults were identified. As the pilot attempted to return to the airfield and broadcast an emergency call, the engine ceased operation.
The pilot managed to execute a glide approach and selected a suitable field of unharvested wheat for a forced landing. The aircraft landed successfully, though the nosewheel sustained damage during the maneuver. There were no injuries to the pilot or the passenger.
The investigation
Following the incident, the AAIB examined the engine to determine the cause of the power loss. The inspection revealed that the engine oil filter had become loose, which allowed oil to escape under pressure. This loss of oil led to the seizure of a connecting rod big end. The resulting internal damage was so extensive that the engine was rendered beyond economic repair.
Investigators also examined the physical condition of the filter installation. They found evidence that the threads had been damaged during the process of installing the filter. Notably, the oil filter on this engine type is a screw-on type that lacks a locking device, and the investigators noted that the UK distributor for the engine had only been aware of one other instance of a filter working loose.
Findings
- The engine failure was caused by oil starvation.
- The oil starvation resulted from the oil filter working loose.
- Evidence suggested the filter threads had been damaged during installation.