What happened
On 28 June 2000, a Reims Cessna F152, registration G-BXRN, departed Exeter Airport carrying an instructor and a student for a training session involving stalling and spinning maneuvers. During the return leg of the flight, approximately one mile east of Tiverton, the aircraft's engine failed and could not be restarted. The pilot issued a Mayday call and set the transponder to 7700.
While attempting to locate a suitable landing site, the pilot identified a field for a forced landing. However, at an altitude of approximately 100 feet, it became apparent that the chosen area, along with the surrounding fields, contained standing cereal crops. During the low-speed approach into the field, the nosewheel became embedded in the crop, causing the aircraft to invert. Both occupants exited the wreckage without injury, though the aircraft sustained damage beyond economic repair.
The investigation
Following the accident, the aircraft was moved to a maintenance facility to determine the cause of the engine failure. Upon inspecting the induction system, investigators removed the air filter and carburettor heat boxes. This revealed a crumpled piece of paper, approximately half of an A4 sheet, lodged within the throat of the carburettor. The paper was partially obstructing the airflow. The paper contained no identifying information other than some red ballpoint pen markings.
Investigators examined recent maintenance history, noting that a 50-hour check had recently been completed, though this procedure did not involve dismantling the induction system. The last time such components would have been accessed was during an annual inspection roughly 50 flying hours prior, which was conducted by a different company. It was also considered that the paper could have been present in a replacement carburettor heat hose, though no evidence of recent part replacement was found.