What happened
During the landing roll of the flight, the pilot in command (PIC) experienced a noticeable vibration as the aircraft's tailwheel made contact with the runway surface. In an effort to minimize this vibration, the pilot lifted the tailwheel off the ground.
This action caused the aircraft to begin ground looping to the right, directing it toward a nearby pole. To regain control or stop the movement, the pilot applied heavy pressure to the wheel brakes. This aggressive braking input caused the nose of the aircraft to pitch forward violently, resulting in the aircraft nosing over into an inverted position.
The investigation
The investigation focused on the sequence of events during the landing roll. Examination of the aircraft confirmed that the nose-over occurred as a direct result of the heavy application of wheel brakes after the tailwheel was lifted from the runway surface.
Findings
The primary factors contributing to this accident were the pilot's decision to lift the tailwheel to reduce vibration and the subsequent heavy application of wheel brakes, which caused the nose-over. The aircraft ended up in an inverted position due to these actions.