Pilot/Controller Glossary

airways/jet routes, or a published procedure (STAR
Transition) used to connect one of several en route
airways/jet routes to the basic STAR.
(Refer to DP/STAR Charts.)

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.
TRANSITION WAYPOINT- The waypoint that
defines the beginning of a runway or en route
transition on an RNAV SID or STAR.
TRANSITIONAL AIRSPACE- That portion of
controlled airspace wherein aircraft change from one
phase of flight or flight condition to another.
TRANSMISSOMETER- An apparatus used to
determine visibility by measuring the transmission of
light through the atmosphere. It is the measurement
source for determining runway visual range (RVR)
and runway visibility value (RVV).
(See VISIBILITY.)

TRANSMITTING IN THE BLIND- A transmission from one station to other stations in
circumstances where two-way communication
cannot be established, but where it is believed that the
called stations may be able to receive the
transmission.
TRANSPONDER- The airborne radar beacon
receiver/transmitter portion of the Air Traffic Control
Radar Beacon System (ATCRBS) which automatically receives radio signals from interrogators on the
ground, and selectively replies with a specific reply
pulse or pulse group only to those interrogations
being received on the mode to which it is set to
respond.
(See INTERROGATOR.)
(See ICAO term TRANSPONDER.)
(Refer to AIM.)

TRANSPONDER OBSERVED - Phraseology used
to inform a VFR pilot the aircraft"s assigned beacon
code and position have been observed. Specifically,
this term conveys to a VFR pilot the transponder
reply has been observed and its position correlated for
transit through the designated area.
TRIAL PLAN- A proposed amendment which
utilizes automation to analyze and display potential
conflicts along the predicted trajectory of the selected
aircraft.
TRSA-
(See TERMINAL RADAR SERVICE AREA.)

TSD-
(See TRAFFIC SITUATION DISPLAY.)

TURBOJET AIRCRAFT- An aircraft having a jet
engine in which the energy of the jet operates a
turbine which in turn operates the air compressor.
TURBOPROP AIRCRAFT- An aircraft having a jet
engine in which the energy of the jet operates a
turbine which drives the propeller.
TURBULENCE- An atmospheric phenomenon that
causes changes in aircraft altitude, attitude, and or
airspeed with aircraft reaction depending on
intensity. Pilots report turbulence intensity according
to aircraft"s reaction as follows:
a. Light - Causes slight, erratic changes in altitude
and or attitude (pitch, roll, or yaw).
b. Moderate- Similar to Light but of greater
intensity. Changes in altitude and or attitude occur
but the aircraft remains in positive control at all times.
It usually causes variations in indicated airspeed.
c. Severe- Causes large, abrupt changes in altitude
and or attitude. It usually causes large variations in
indicated airspeed. Aircraft may be momentarily out
of control.
d. Extreme- The aircraft is violently tossed about
and is practically impossible to control. It may cause
structural damage.
(See CHOP.)
(Refer to AIM.)

TRANSPONDER [ICAO]- A receiver/transmitter
which will generate a reply signal upon proper
interrogation; the interrogation and reply being on
different frequencies.

TVOR-

TRANSPONDER CODES-

TWEB-

(See CODES.)

TURN ANTICIPATION- (maneuver anticipation).
(See TERMINAL-VERY HIGH FREQUENCY
OMNIDIRECTIONAL RANGE STATION.)
(See TRANSCRIBED WEATHER BROADCAST.)