AD 2021-06-10 Prohibits Operation Of An Airplane With Any Inoperative Refuel Valve
The FAA is adopting a new airworthiness directive (AD) for all The Boeing Company Model 747 series airplanes and Model 767 series airplanes. This AD was prompted by a report of an un-commanded fuel transfer between the main and center fuel tanks. This AD prohibits operation of an airplane with any inoperative refuel valve (fueling shut-off valve) failed in the open position. The FAA is issuing this AD to address the unsafe condition on these products. This AD is effective April 28, 2021.