Airworthiness Directives; Bombardier Model DHC-8-400 Series Airplanes

The FAA is adopting a new airworthiness directive (AD) for certain Bombardier Model DHC-8-400 series airplanes. This AD requires a one-time inspection of the fuel and hydraulic tubes, and corrective actions if necessary. This AD also requires modifying fairlead plate assemblies. This AD results from reports of chafing between fuel and hydraulic tubes and the fairlead plate where the tubes pass through the firewall. We are issuing 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.