Accident Overview
A pilot taxied an airplane from the parking area to the end of the runway for takeoff, a distance of about 1.5 miles. During the taxi, the pilot kept the right brake applied to maintain alignment with the taxiway. After turning onto the runway, the passenger observed flames emanating from the area of the right main landing gear brake.
Damage
The fire resulted in structural damage to the right wing of the airplane.
Pilot Statement
The pilot reported that for several months preceding the incident, the airplane had been 'pulling left' during taxi. To compensate, the pilot had to drag the right brake to taxi straight.
Maintenance History
Two weeks before the accident, the pilot informed maintenance of the pulling issue. Maintenance personnel discovered a fluid leak from the left brake cylinder and assembly, which was repaired, and the airplane was returned to service. Three days prior to the accident, a further report was made to maintenance indicating that the left brake was pulling excessively.
Operating Manual Guidance
Section 4 of the airplane's operating manual contained a caution note directing pilots to taxi with the minimum power necessary for forward movement. The note stated that excessive braking could result in overheated or damaged brakes, which could lead to brake system malfunction or failure.