- F -

Feeder Airline: An air carrier that services a local market and "feeds" traffic to the national and international carriers.

Filter: A device used to alter a signal.

Fireproof: (1) With respect to materials and parts used to confine fire in a designated fire zone, means the capacity to withstand at least as well as steel in dimensions appropriate for the purpose for which they are used, the heat produced when there is a severe fire of extended duration in that zone; and (2) With respect to other materials and parts, means the capacity to withstand the heat associated with fire at least as well as steel in dimensions appropriate for the purpose for which they are used. 

Fire Resistant: (1) With respect to sheet or structural members means the capacity to withstand the heat associated with fire at least as well as aluminum alloy in dimensions appropriate for the purpose for which they are used; and (2) With respect to fluid-carrying lines, fluid system parts, wiring, air ducts, fittings, and power plant controls, means the capacity to perform the intended functions under the heat and other conditions likely to occur when there is a fire at the place concerned. 

Final Judgment: The written ruling on a lawsuit by the judge who presided at trial. This completes the case unless it is appealed to a higher court. Also called a final decree or final decision.

Flight Control System: A primary or automatic flight control system. 

Flight Controls: Controls placed in a cockpit, which are used specifically for flying an aircraft. The primary flight controls are the wheel, yoke, cyclic, pedals, throttle, and collective. Secondary flight controls are flight controls that are not primary and include the flaps, slats, stabilizer, and landing gear.

Flight Director: A system, usually in the form of software, which generates stick position cues from state errors. There are typically three cues: the pitch, roll, and throttle for fixed-wing and longitudinal cyclic, lateral cyclic, and collective for rotary wing. 

Flight Time: (1) Pilot time that commences when an aircraft moves under its own power for the purpose of flight and ends when the aircraft comes to rest after landing; or (2) For a glider without self-launch capability, pilot time that commences when the glider is towed for the purpose of flight and ends when the glider comes to rest after landing. 

Flight Plan: A predetermined route, possibly including guidance modes, communications, and mission objectives, used by guidance and mission management for planning. Included in a flight plan may be navigation reference points, waypoints, and mode commands for navigation, radio navigation, guidance, and flight direction. 

Fly Over: A position that a pilot takes when he is flying directly over a known point.

Foreign Air Commerce: The carriage by aircraft of persons or property for compensation or hire, or the carriage of mail by aircraft, or the operation or navigation of aircraft in the conduct or furtherance of a business or vocation, in commerce between a place in the United States and any place outside thereof; whether such commerce moves wholly by aircraft or partly by aircraft and partly by other forms of transportation.

Forward-Looking Infrared: Sensor equipment used to supplement AGR, extend the aircraft visual search capability and provide position information for guidance and navigation update capability. Imagery derived from the FLIR sensor is displayed in the cockpit. FLIR pointing can be controlled manually using a tracking handle or automatically by the Mission Computer. FLIR converts a heat image into a video image and determines azimuth, elevation, and sometimes range of a point.