What happened
On 26 September 2003, a Europa aircraft, registration G-BZHS, was conducting a training flight at Cambridge Airport. The flight was part of a conversion course, with an instructor and a student pilot on board. Following the completion of pre-landing checks, both crew members had verified that the landing gear lever was in the down and latched position.
Upon landing on the grass runway, the aircraft experienced a firm touchdown. The aircraft initially rolled on its wheels for roughly 15 to 20 metres; however, the mainwheel, outrigger wheels, and flaps subsequently retracted. This caused the aircraft to continue along the runway on its belly for an additional 180 metres before coming to a stop. There were no injuries to the crew, though the aircraft sustained damage to the propeller, engine shock-loading, and the main wheel tunnel.
The investigation
Investigators examined the aircraft's landing gear mechanism, which is a complex system where the gear lever operates the mainwheel, outrigger wheels, and flaps simultaneously through a single linkage. The investigation focused on the over-centre mechanism and the safety latch designed to prevent the lever from moving out of the down gate.
An inspection conducted by the aircraft manufacturer's engineer confirmed that the landing gear assembly was structurally sound and functioning as designed. The gear lever was correctly biased to engage the down gate, and the retraction arms were properly positioned over-centre. The safety latch was also found to operate freely without defect.
Findings
- The investigation established that the landing gear assembly was in proper working order and the lever was capable of locking in the down position.
- The unlatching of the gear lever was the primary cause of the gear retraction.
- It was determined that the gear lever must have been unlatched during the landing roll, either because the safety latch was not fully seated in its guide slot or because the latch moved out of position due to the aircraft traversing uneven ground.