What happened
During the aircraft's rollout phase following landing, the pilot was unable to maintain directional control. The airplane departed the paved surface on the left side and collided with a ditch. Prior to this incident, the pilot had reported experiencing a problem with the left brake system.
The investigation
A thorough examination of the landing gear was conducted to determine the cause of the reported brake issue. This mechanical inspection failed to disclose any evidence of a malfunction or defect in the braking system. Additionally, the investigation uncovered evidence indicating that the airplane had been porpoising on the runway several times prior to departing the surface.
Findings
The primary factor contributing to the accident was the loss of directional control during the critical rollout phase. While the pilot initially attributed handling difficulties to a mechanical brake failure, the physical evidence pointed to other causes, including observed porpoising behavior on the runway.