Accident Overview
A tailwheel-equipped airplane experienced a ground loop during the landing rollout. The pilot reported that a normal approach and landing was conducted, but control was lost at approximately 40 knots during the rollout. The airplane ground-looped to the right.
Pilot Report
The pilot stated that proper control inputs and operation were utilized until rudder authority became ineffective. The pilot noted that the tailwheel steering did not seem to work and that use of asymmetric braking had no effect. The pilot reported negligible wind conditions at the time.
Runway Evidence
Examination of the runway revealed a faint tire-track mark 336 feet in length curving toward the right, consistent with being left by the left main landing gear. The airplane traveled an additional 57 feet after the left main landing gear had separated from the fuselage.
Aircraft Damage and Component Examination
The left main landing gear spring fractured due to higher than normal side loads experienced during the ground-loop encounter. The tailwheel assembly was inspected after the accident, and no anomalies were found with the strut, wheel, or steering linkages. The piston-rod for the left brake master cylinder was found fractured in two portions. The rod fractured at the mid-span snap ring groove. The master cylinder cover was deformed downward, adjacent to the center hole where the rod passed through the cover.