Summary
The FAA proposes to adopt a new airworthiness directive (AD) for all The Boeing Company Model 747-400, -400D, and -400F series airplanes. This proposed AD was prompted by the FAA's analysis of the Model 747 airplane fuel system reviews conducted by the manufacturer, and by the determination that new or more restrictive airworthiness limitations are necessary. This proposed AD would require revising the existing maintenance or inspection program, as applicable, to incorporate new or more restrictive airworthiness limitations. The FAA is proposing this AD to address the unsafe condition on these products.