Pilot/Controller Glossary REFERENCE- Pilot"s Handbook of Aeronautical Knowledge, FAA-H-8083-25, Chapter 14, Airport Operations, Traffic Patterns. (See STRAIGHT-IN APPROACH VFR.) (See TAXI PATTERNS.) (See ICAO term AERODROME TRAFFIC CIRCUIT.) (Refer to 14 CFR Part 91.) (Refer to AIM.) TRAFFIC SITUATION DISPLAY (TSD)- TSD is a computer system that receives radar track data from all 20 CONUS ARTCCs, organizes this data into a mosaic display, and presents it on a computer screen. The display allows the traffic management coordinator multiple methods of selection and highlighting of individual aircraft or groups of aircraft. The user has the option of superimposing these aircraft positions over any number of background displays. These background options include ARTCC boundaries, any stratum of en route sector boundaries, fixes, airways, military and other special use airspace, airports, and geopolitical boundaries. By using the TSD, a coordinator can monitor any number of traffic situations or the entire systemwide traffic flows. TRAJECTORY- A EDST representation of the path an aircraft is predicted to fly based upon a Current Plan or Trial Plan. (See EN ROUTE DECISION SUPPORT TOOL.) TRAJECTORY-BASED OPERATIONS (TBO)- An Air Traffic Management method for strategically planning and managing flights throughout the operation by using Time-Based Management (TBM), information exchange between air and ground systems, and the aircraft"s ability to fly trajectories in time and space. Aircraft trajectory is defined in four dimensions " latitude, longitude, altitude, and time. TRAJECTORY MODELING- The automated process of calculating a trajectory. TRAJECTORY OPTIONS SET (TOS)- A TOS is an electronic message, submitted by the operator, that is used by the Collaborative Trajectory Options Program (CTOP) to manage the airspace captured in the traffic management program. The TOS will allow the operator to express the route and delay trade-off options that they are willing to accept. TRANSFER OF CONTROL- That action whereby the responsibility for the separation of an aircraft is transferred from one controller to another. (See ICAO term TRANSFER OF CONTROL.) TRANSFER OF CONTROL [ICAO]- Transfer of responsibility for providing air traffic control service. TRANSFERRING CONTROLLER- A controller/facility transferring control of an aircraft to another controller/facility. (See ICAO term TRANSFERRING UNIT/CONTROLLER.) TRANSFERRING FACILITY- (See TRANSFERRING CONTROLLER.) TRANSFERRING UNIT/CONTROLLER [ICAO]- Air traffic control unit/air traffic controller in the process of transferring the responsibility for providing air traffic control service to an aircraft to the next air traffic control unit/air traffic controller along the route of flight. Note: See definition of accepting unit/controller. TRANSITION- The general term that describes the change from one phase of flight or flight condition to another; e.g., transition from en route flight to the approach or transition from instrument flight to visual flight. TRANSITION POINT- A point at an adapted number of miles from the vertex at which an arrival aircraft would normally commence descent from its en route altitude. This is the first fix adapted on the arrival speed segments. TRANSITIONAL AIRSPACE- That portion of controlled airspace wherein aircraft change from one phase of flight or flight condition to another.