Summary
This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Boeing Model 757 series airplanes. This proposal would require repetitive detailed inspections of the support brackets and associated fasteners for the hydraulic lines located in the nacelle struts, and related investigative and corrective actions as necessary. This proposal also provides an optional terminating action for the repetitive inspections. This action is necessary 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. This action is intended to address the identified unsafe condition.