Summary
The FAA proposes to adopt a new airworthiness directive (AD) for certain Boeing Model 757 series airplanes. This proposed AD would require repetitive inspections for loose or damaged components of the support brackets and associated fasteners for the hydraulic lines located in the nacelle struts, and any related investigative and corrective actions. This proposed AD is prompted by reports of damage and subsequent failure of the support brackets and associated fasteners for the hydraulic lines located internal to the upper fairing cavity of the nacelle struts. We are proposing this AD to prevent flammable fluids from leaking into the interior compartment of the nacelle struts where ignition sources exist, which could result in the ignition of flammable fluids and an uncontained fire.