Action
Notice of proposed rulemaking (NPRM).
Summary
We propose to supersede an existing airworthiness directive (AD) that applies to certain The Boeing Company Model 767 airplanes. The existing AD currently requires sealing certain fasteners and stiffeners in the fuel tank, changing certain wire bundle clamp configurations on the fuel tank walls, inspecting certain fasteners in the fuel tanks and determining the method of attachment of the vortex generators, and performing corrective action if necessary. We issued that AD to prevent possible ignition sources in the auxiliary (center) fuel tank, main fuel tanks, and surge tanks caused by a wiring short or lightning strike, which could result in fuel tank explosions and consequent loss of the airplane. Since we issued that AD, another possible ignition source location was identified. This proposed AD would add a general visual inspection for the presence of a polytetrafluoroethylene (TFE) sleeve at the clamp location on the rear spar, and installation of a TFE sleeve if necessary. This proposed AD would also add airplanes to the applicability. We are proposing this AD to correct the unsafe condition on these products.