Airworthiness Directives; The Boeing Company Airplanes

FAA / Federal Register · 2023-26367

The FAA is adopting a new airworthiness directive (AD) for all The Boeing Company Model 747 airplanes. This AD was prompted by reports of latent failures of the lightning protection features for the engine fuel feed system. This AD requires an inspection for damage and a measurement of the electrical bonding resistance of the out-tank fuel feed tube bonding jumper in the strut for each of the four engines, a measurement of the electrical bonding resistance of the forward side of the front spar bulkhead fitting adapter for each of the four engines, and applicable related investigative and corrective actions. The FAA is issuing this AD to address the unsafe condition on these products.