Glossary

False horizon. Inaccurate visual information for aligning the Flight director indicator (FDI). One of the major aircraft, caused by various natural and geometric formations components of a flight director system, it provides steering that disorient the pilot from the actual horizon. commands that the pilot (or the autopilot, if coupled) follows. FDI. See flight director indicator. Flight level (FL). A measure of altitude (in hundreds of feet) used by aircraft flying above 18,000 feet with the altimeter Federal airways. Class E airspace areas that extend upward set at 29.92 "Hg. from 1,200 feet to, but not including, 18,000 feet MSL, unless otherwise specified. Flight management system (FMS). Provides pilot and crew Feeder facilities. Used by ATC to direct aircraft to with highly accurate and automatic long-range navigation intervening fixes between the en route structure and the capability, blending available inputs from long- and short- initial approach fix. range sensors. Final approach. Part of an instrument approach procedure in Flight path. The line, course, or track along which an aircraft which alignment and descent for landing are accomplished. is flying or is intended to be flown. Final approach fix (FAF). The fix from which the IFR Flight patterns. Basic maneuvers, flown by reference to the final approach to an airport is executed, and which identifies instruments rather than outside visual cues, for the purpose the beginning of the final approach segment. An FAF is of practicing basic attitude flying. The patterns simulate designated on government charts by a Maltese cross symbol maneuvers encountered on instrument flights such as holding for nonprecision approaches, and a lightning bolt symbol for patterns, procedure turns, and approaches. precision approaches. Flight strips. Paper strips containing instrument flight Fixating. Staring at a single instrument, thereby interrupting information, used by ATC when processing flight plans. the cross-check process. FMS. See flight management system. Fixed-pitch propellers. Propellers with fixed blade angles. Fixed-pitch propellers are designed as climb propellers, FOD. See foreign object damage. cruise propellers, or standard propellers. Fog. Cloud consisting of numerous minute water droplets Fixed slot. A fixed, nozzle shaped opening near the leading and based at the surface; droplets are small enough to be edge of a wing that ducts air onto the top surface of the wing. suspended in the earth’s atmosphere indefinitely. (Unlike Its purpose is to increase lift at higher angles of attack. drizzle, it does not fall to the surface. Fog differs from a cloud only in that a cloud is not based at the surface, and FL. See flight level. is distinguished from haze by its wetness and gray color.) Flameout. A condition in the operation of a gas turbine Force (F). The energy applied to an object that attempts to engine in which the fire in the engine goes out due to either cause the object to change its direction, speed, or motion. too much or too little fuel sprayed into the combustors. In aerodynamics, it is expressed as F, T (thrust), L (lift), W (weight), or D (drag), usually in pounds. Flaps. Hinged portion of the trailing edge between the ailerons and fuselage. In some aircraft ailerons and flaps are Foreign object damage (FOD). Damage to a gas turbine interconnected to produce full-span “flaperons.” In either engine caused by some object being sucked into the engine case, flaps change the lift and drag on the wing. while it is running. Debris from runways or taxiways can cause foreign object damage during ground operations, and Floor load limit. The maximum weight the floor can sustain the ingestion of ice and birds can cause FOD in flight. per square inch/foot as provided by the manufacturer. Form drag. The drag created because of the shape of a Flight configurations. Adjusting the aircraft control surfaces component or the aircraft. (including flaps and landing gear) in a manner that will achieve a specified attitude. G-12