Landing and Swerving
The pilot landed on runway 18L. During the landing rollout, the airplane swerved to the right when brakes were applied. The pilot corrected back to the runway centerline using rudder. A second application of brakes again caused a right swerve, which was again corrected. Upon a third brake application, the airplane swerved right once more. The pilot then applied the emergency brake. The airplane subsequently departed the right side of the runway and struck the concrete pad of a runway marker sign.
Post-Incident Inspection
An FAA inspector reported finding hydraulic fluid covering the left main landing gear. The inspector stated that the main and auxiliary left brake lines were both fractured. Additionally, the right main landing gear tire was described as "shredded off the wheel."
Brake Line Examination
According to the NTSB's Materials Laboratory Factual Report, the main brake line transmits hydraulic fluid, while the auxiliary brake line transmits compressed nitrogen. Both brake line fractures were determined to be the result of fatigue cracking. No mechanical or other damage was evident on the exterior of the lines in the initiation area. Maintenance records dating back to the airplane's date of manufacture indicated that the brake lines had never been removed or replaced.