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