Airworthiness Directives; Fokker Model F27 Mark 050 Airplanes

The FAA is adopting a new airworthiness directive (AD) for all Fokker Model F27 Mark 050 airplanes. This AD requires a one-time inspection of the bleed air supply ducts to determine if blanking plugs are present and a one-time inspection of the entire area of the engine nacelle for heat damage; and corrective actions if necessary. This AD also requires replacement of the blanking plugs with clamping devices. This AD results from heat damage in areas adjacent to the bleed air supply duct assembly. We are issuing this AD to prevent rupture of the bleed air supply duct, which could lead to hot bleed air leaking into the engine controls area and result in heat damage to control cables, electrical wiring, hydraulic components, and fuel lines, and consequent fire.