Incident Overview
On 16 October 2003, at 1301 hours UTC, a Robinson R22 Beta helicopter, registration G-DELT, was involved in an accident at Coventry Airport, West Midlands. The aircraft, manufactured in 1988, was operated on a training flight. The sole occupant was a 21-year-old student pilot with 25 hours of flying experience, all on type. The helicopter was destroyed beyond economic repair; the pilot was uninjured.
Sequence of Events
The student had been sent by the Chief Flying Instructor to perform pre-flight checks and start the helicopter. The instructor intended to board after start-up with rotors running. The helicopter was parked into wind (090° at 13 kt). After starting the engine and proceeding with after-start checks, the instructor, approximately 20 feet away, witnessed the aircraft yaw rapidly to the left, turn through about 360°, and become airborne. As it continued turning, the front of the left skid contacted the ground, causing the aircraft to roll onto its left side. The engine stopped; the student was assisted from the right-hand door by the instructor.
Engineering Inspection
An engineering inspection revealed no apparent technical failures.
Pilot and Circumstances
The student had completed pre-flight checks up to the low rotor rpm warning horn check. This check requires the throttle set at 104%, raising the collective lever slightly to break a microswitch, then closing the throttle to reduce rpm below 97% to trigger the warning. The school's checklist required collective and cyclic frictions to remain engaged during this check. The student was 6'4" tall; the R22's pedals are not adjustable. This may have caused him to unknowingly apply some left yaw pedal. If the collective was raised excessively, the aircraft could be light on its skids and yaw left on the ground. The combination of low experience, surprise, applied frictions, and the prevailing wind may have made control difficult, and the skid contacted the ground, rolling the aircraft.
Regulatory Context
The CAA was proposing an amendment to Article 41 of the Air Navigation Order to require that a person at the controls entitled to act as pilot-in-command be present whenever a helicopter rotor is turned under power for flight.