What happened
On 21 September 2014, a Robinson R22 Beta, registration G-OKEY, was engaged in a training flight at Elstree Aerodrome. During an introductory lesson, the instructor initially flew the aircraft through the circuit to the north of the airfield. Upon reaching the downwind leg, the instructor transferred control of the cyclic stick to the student.
The student operated the aircraft through the remainder of the circuit until the altitude reached approximately 300 ft agl, at which point the instructor resumed control. The aircraft was then flown to the designated hovering area, where the instructor once again handed control of the cyclic to the student. After the student had been hovering for roughly one minute, the instructor applied slight forward pressure to the cyclic to adjust a nose-high attitude. At this moment, the student responded with a sudden, heavy rearward input on the stick and subsequently became unresponsive. The helicopter struck the ground in a nose-high, right-skid-low orientation. The impact caused the main rotor to strike the terrain, resulting in the aircraft spinning 180 degrees. The aircraft remained upright but suffered a collapsed right skid. The one crew member on board sustained minor injuries.
The investigation
The investigation was based on the aircraft accident report submitted by the pilot. Investigators examined the sequence of events leading to the impact and the physical state of the aircraft. The investigation focused on the transition of control between the instructor and the student and the specific control inputs made during the hovering phase. The aircraft sustained substantial damage to the fuselage, windscreen, skids, and main rotor.