Summary
The FAA proposes to adopt a new airworthiness directive (AD) for all The Boeing Company Model 747 airplanes and Model 767 airplanes. This proposed AD was prompted by a report of an un-commanded fuel transfer between the main and center fuel tanks. This proposed AD would prohibit operation of an airplane with any inoperative refuel valve (fueling shut-off valve) secured in the open position. The FAA is proposing this AD to address the unsafe condition on these products.