Glossary

TEC. See Tower En Route Control. Terrain awareness and warning system (TAWS). A timed-based system that provides information concerning Technique. The manner in which procedures are executed. potential hazards with fixed objects by using GPS positioning and a database of terrain and obstructions to provide true Telephone information briefing service (TIBS). An FSS predictability of the upcoming terrain and obstacles. service providing continuously updated automated telephone recordings of area and/or route weather, airspace procedures, TFR. See temporary flight restriction. and special aviation-oriented announcements. Thermosphere. The last layer of the atmosphere that begins Temporary flight restriction (TFR). Restriction to flight above the mesosphere and gradually fades away into space. imposed in order to: Threshold crossing height (TCH). The theoretical height 1. Protect persons and property in the air or on the surface above the runway threshold at which the aircraft’s glideslope from an existing or imminent flight associated hazard; antenna would be if the aircraft maintained the trajectory 2. Provide a safe environment for the operation of established by the mean ILS glideslope or MLS glidepath. disaster relief aircraft; 3. Prevent an unsafe congestion of sightseeing aircraft Thrust. The force which imparts a change in the velocity of a above an incident; mass. This force is measured in pounds but has no element of time or rate. The term “thrust required” is generally associated 4. Protect the President, Vice President, or other public with jet engines. A forward force which propels the airplane figures; and, through the air. 5. Provide a safe environment for space agency operations. Thrust (aerodynamic force). The forward aerodynamic Pilots are expected to check appropriate NOTAMs during force produced by a propeller, fan, or turbojet engine as it flight planning when conducting flight in an area where a forces a mass of air to the rear, behind the aircraft. temporary flight restriction is in effect. Thrust line. An imaginary line passing through the center of Tension. Maintaining an excessively strong grip on the control the propeller hub, perpendicular to the plane of the propeller column, usually resulting in an overcontrolled situation. rotation. Terminal aerodrome forecast (TAF). A report established Time and speed table. A table depicted on an instrument for the 5 statute mile radius around an airport. Utilizes the approach procedure chart that identifies the distance from the same descriptors and abbreviations as the METAR report. FAF to the MAP, and provides the time required to transit that distance based on various groundspeeds. Terminal arrival area (TAA). A procedure to provide a new transition method for arriving aircraft equipped with Timed turn. A turn in which the clock and the turn FMS and/or GPS navigational equipment. The TAA contains coordinator are used to change heading a definite number a “T” structure that normally provides a NoPT for aircraft of degrees in a given time. using the approach. TIS. See traffic information service. Terminal instrument approach procedure (TERP). Prescribes standardized methods for use in designing Title 14 of the Code of Federal Regulations (14 CFR). instrument flight procedures. Includes the federal aviation regulations governing the operation of aircraft, airways, and airmen. TERP. See terminal instrument approach procedure. Torque. (1) A resistance to turning or twisting. (2) Forces that Terminal radar service areas (TRSA). Areas where produce a twisting or rotating motion. (3) In an airplane, the participating pilots can receive additional radar services. The tendency of the aircraft to turn (roll) in the opposite direction purpose of the service is to provide separation between all of rotation of the engine and propeller. (4) In helicopters with IFR operations and participating VFR aircraft. a single, main rotor system, the tendency of the helicopter to turn in the opposite direction of the main rotor rotation. G-30