Summary
The FAA proposes to adopt a new airworthiness directive (AD) for certain Boeing Model 767 series airplanes. This proposed AD would require performing a test of the bonding resistance between the engine fuel feed tube fitting and the front spar, applying sealant on a hex nut inside the dry bay, and performing any applicable corrective actions. This proposed AD is prompted by a report that the engine fuel feed tubes were found not electrically bonded to the front spar. We are proposing this AD to prevent an ignition source from entering the fuel tank during a lightning strike event, which could cause a fuel tank explosion.