What happened
On 6 December 1998, a Streak Shadow, registration G-BUVX, was conducting a flight when the engine failed. The pilot was forced to perform a landing at a farm strip located near East Fortune, Scotland. During the descent following the loss of power, the pilot maintained a glide speed of 48 knots, which corresponded to the manufacturer's placarded best glide speed (minimum sink rate). However, the pilot's use of a standard glide approach led to a miscalculation regarding the aircraft's height and the remaining distance of the runway.
The investigation
While an earlier report suggested that carburettor icing might have caused the engine failure, subsequent examination of the engine provided different findings. A strip examination of the powerplant revealed that the front cylinder had seized. This seizure was attributed to an excessive accumulation of ash and carbon deposits within the cylinders, with the front cylinder being the most severely affected.
Additionally, the investigation clarified the aircraft's classification and the pilot's flight parameters. At an all-up weight of 409 kg, the G-BUVX was classified as an aeroplane under UK regulations rather than a microlight. The investigation also noted that the pilot's approach, while following standard procedures, contributed to the difficulty in judging the landing site's dimensions.