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.

Supplementary Information: The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 by adding an AD that would apply to all The Boeing Company Model 747 series airplanes and Model 767 series airplanes. The NPRM published in the Federal Register on September 9, 2020 (85 FR 55622). The NPRM was prompted by a report of an un-commanded fuel transfer between the main and center fuel tanks. The NPRM proposed to prohibit 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 multiple refuel valves failed in the “open” position via Master Minimum Equipment List (MMEL) dispatch allowance, which allows un-commanded fuel transfer between fuel tanks. This condition could result in a fuel exhaustion event.

FMI: www.regulations.gov