What happened
On 17 November 2002, a Rans S6-ES Coyote II, registration G-CBUY, was being used for refresher training at Rufforth Aerodrome, York. The flight was being conducted by a pilot and an instructor to prepare for a Certificate of Test renewal. During the pre-flight inspection, the fuel levels were checked, with the pilot noting two gallons in the left tank and approximately five gallons in the right tank. The left tank was selected for the flight.
During taxiing for takeoff from Runway 24, the instructor noted that the engine sounded rough, though the pilot believed this was typical for the Rotax 582-48 engine and gearbox setup. As the engine speed increased above 2,800 RPM, the roughness was no longer apparent. Following standard power checks, the aircraft departed without flaps and lifted off at approximately 45 mph.
While climbing, the aircraft reached a speed of 60 mph and established a positive rate of climb. However, at an altitude of between 60 and 70 feet, the engine RPM dropped to idle despite the throttle remaining in the fully open position. The pilot performed a nose-down maneuver to attempt a landing on the remaining runway. Although a rapid flare was executed, the aircraft experienced a moderately heavy landing with no bounce, causing minor damage to the landing gear and cockpit.
The investigation
The investigation was based on the aircraft accident report form submitted by the pilot. Investigators examined the engine performance and the environmental conditions present during the flight. The pilot noted that the weather conditions were suitable for the formation of carburettor ice, even though the aircraft was equipped with a permanently active carburettor icing protection system. Following the incident, subsequent flights using the same engine and aircraft combination were conducted, and no further engine defects were identified.