What happened
On 5 April 2015, a Tanarg/Ixess 15 912S(1), registration G-IMUP, was involved in a ground accident at Dunkeswell Airfield in Devon. The aircraft was being operated by a student pilot during a training flight. Prior to the incident, the pilot had been running the engine at 2,000 rpm for ten minutes to facilitate a warm-up.
During the engine shutdown sequence, the pilot retarded the throttle to idle, selected magneto 1, and turned the ignition switch to the off position. After five minutes, the pilot attempted to restart the engine. While performing the shutdown procedure again, the pilot noted the engine was running roughly on magneto 1. Upon switching the ignition to the off position, the engine failed to stop; instead, it surged to full power after approximately three seconds. Despite heavy application of the brakes, the aircraft moved forward. The pilot steered the aircraft to avoid other parked planes but ultimately struck two parked cars. The pilot, who had not yet fastened his seat straps, rolled out of the trike before the impact, resulting in one minor injury to his hand.
The investigation
Investigators examined the aircraft's throttle and ignition systems following the collision. The assessment revealed no defects in the throttle or ignition components that would have caused the engine to run up to power after the ignition was switched off. The investigation also considered the pilot's experience and familiarity with the specific aircraft type.
Findings
- The engine surged to high power immediately after the ignition was switched off.
- Relative unfamiliarity with the aircraft's specific engine controls may have contributed to the event, as the pilot's previous experience was primarily on a different type of microlight.
- The aircraft sustained damage beyond economic repair.