The student had been practicing circuits with touch and go landings for about 75 minutes. An approach was then made for a full-stop landing. The aircraft was flared too high, and it subsequently touched down heavily and bounced. The instructor took control and landed the aircraft, but the left wing lowered until it touched the ground. After vacating the aircraft, the crew discovered that the left maingear torque bolt had failed, allowing the wheel and oleo assembly to fall clear of the strut during the bounce. The landings had been conducted in crosswind conditions, and at the time of the last approach the wind strength had increased. The aircraft had touched down heavily while drifting under the effect of the crosswind, and the resulting loads had caused the torque bolt to fail. It was likely that the pilot's performance had been affected by the onset of fatigue, as a result of the lengthy training period under difficult operating conditions.
