What happened
The incident occurred during a dual instructional flight involving a new aircraft owner and an instructor pilot. This was only the second time the pair had flown together in this specific aircraft. The owner, holding a private pilot certificate, was accumulating the ten hours of flight time required by his insurance policy. Approximately thirty minutes into the sortie, following a period of airwork, the crew returned to the airport for landing under light and variable wind conditions.
The approach was reported as normal, resulting in a full stall landing. Upon touchdown, the aircraft began drifting to the left side of the runway. The pilot initially attempted to correct this drift using aileron input. Subsequently, at the instruction of the instructor pilot (IP), he applied right rudder. This control input caused the aircraft to turn toward the right side of the runway, lifting the left main gear and tailwheel off the ground.
The IP stated that he attempted to take control of the aircraft to recover it, but the owner refused to release the flight controls. As a result, the left main landing gear collapsed upon impact with the runway surface.
The investigation
Examination of the wreckage revealed critical mechanical failures in the landing gear assembly. Investigators located the left main landing gear attach bolt within the gear attach hole. The bolt was found to be bent, and its threads were completely stripped off, indicating a catastrophic failure of the fastener that secured the gear.
Findings
The collapse of the left main landing gear was directly linked to the mechanical failure of the attach bolt. Contributing factors included the pilot's failure to release the controls when instructed by the instructor, which prevented recovery from the post-landing drift and exacerbated the damage.