Incident Summary
Following a landing, the pilot reported that the left brake failed after touchdown. Subsequent examination of the aircraft identified that flexible duct tubing was positioned in close proximity to the aluminum brake line. The brake line exhibited evidence of corrosion, while the flexible duct tubing displayed cracking. Further inspection indicated that a leak had resulted in an insufficient amount of fluid in the left main landing gear brake system, which would have restricted the operation of the left brake.
Maintenance History and Manufacturer Requirements
According to the pilot, the aircraft logbook showed that the brake lines had never been replaced. Manufacturer documentation specifies that the pressurization system must be inspected every 200 hours or every year for plumbing condition, security, and loose connections. Additionally, the brake system must be inspected every 200 hours or every year for leaks, hoses for bulges, and deterioration. The last annual maintenance performed included an inspection of the brake lines, but without removal of the structural sheet metal that overlies the pressurization system.
Examination Findings
The corrosion on the aluminum brake line and the cracking of the flexible duct tubing were observed during the examination. The close proximity of these components may have contributed to the condition, though no direct causal link is established. The leak from the brake line led to a deficiency of brake fluid, compromising the operation of the left brake.