Summary
The FAA proposes to adopt a new airworthiness directive (AD) for certain Bombardier Model DHC-8-401 and -402 airplanes. This proposed AD would require a one-time inspection of the fuel and hydraulic tubes, and corrective actions if necessary. This proposed AD would also require modifying fairlead plate assemblies. This proposed AD is prompted by reports of chafing between fuel and hydraulic tubes and the fairlead plate where the tubes pass through the firewall. We are proposing this AD to prevent chafing of the fuel and hydraulic tubes, which could lead to fuel and/or hydraulic fluid leakage in the engine nacelle area and consequent fire or explosion.