What happened
The pilot reported that the flight proceeded normally through approach and touchdown. Upon retracting the flaps and lowering the tailwheel, he applied the brakes to slow the aircraft. The right brake functioned as expected, but the left brake provided no braking action. This asymmetry caused the plane to swerve sharply to the right.
Attempting to correct the path, the pilot advanced the right throttle. However, the engine did not respond immediately. As power increased and the aircraft began to turn back toward the runway, it entered a shallow drainage ditch containing approximately 4 feet of standing water. The impact with the water caused rapid deceleration, resulting in a nose-over attitude.
The investigation
A physical examination of the landing gear revealed that the left brake hydraulic system was spongy and contained air within both the reservoir and the brake lines. This indicated a failure in the braking mechanism's ability to transmit force effectively. The investigation could not determine when the hydraulic system was last inspected or serviced.
Findings
The primary factor leading to the accident was loss of directional control due to the left brake failure during the ground roll. Contributing to the severity of the incident was the aircraft's departure from the paved surface into a water-filled ditch, which arrested forward momentum abruptly and caused the nose to collapse downward.