En Route Flight Advisory Service (EFAS). An en route weather-only AFSS service.
En route high-altitude charts. Aeronautical charts for en route instrument navigation at or above 18,000 feet MSL.
En route low-altitude charts. Aeronautical charts for en route IFR navigation below 18,000 feet MSL.
Equivalent airspeed. Airspeed equivalent to CAS in standard atmosphere at sea level. As the airspeed and pressure altitude increase, the CAS becomes higher than it should be, and a correction for compression must be subtracted from the CAS.
Expect-further-clearance (EFC). The time a pilot can expect to receive clearance beyond a clearance limit.
FAA. Federal Aviation Administration.
FAF. See .nal approach . x.
False horizon. Inaccurate visual information for aligning the aircraft, caused by various natural and geometric formations that disorient the pilot from the actual horizon.
Federal airways. Class E airspace areas that extend upward from 1,200 feet to, but not including, 18,000 feet MSL, unless otherwise speci. ed.
Feeder facilities. Used by ATC to direct aircraft to intervening .xes between the en route structure and the initial approach . x.
Final approach. Part of an instrument approach procedure in which alignment and descent for landing are accomplished.
Final approach fix (FAF). The .x from which the IFR .nal approach to an airport is executed, and which identi. es the beginning of the .nal approach segment. An FAF is designated on government charts by a Maltese cross symbol for nonprecision approaches, and a lightning bolt symbol for precision approaches.