Also known as: fl.
FL has various meanings in the Federal Aviation Administration category. Discover the full forms, definitions, and usage contexts of FL in Federal Aviation Administration.
Altitude at barometric setting of 1013.2 millibars or 29.92 inches of mercury, expressed in rounds hundreds of feet. This is usual mostly above 18,000 feet. FL350 is 35,000 feet.
Federal Aviation AdministrationLast updated: