CALCULATED LANDING TIME -- CWA
CALCULATED LANDING TIME- A term that may be used in place of tentative or
actual calculated landing time, whichever applies.
CALL UP- Initial voice contact between a facility and an aircraft, using the
identification of the unit being called and the unit initiating the call.
CALL FOR RELEASE- Wherein the overlying ARTCC
requires a terminal facility to initiate verbal coordination to secure ARTCC
approval for release of a departure into the en route environment.
CANADIAN MINIMUM NAVIGATION PERFORMANCE SPECIFICATION AIRSPACE- That portion
of Canadian domestic airspace within which MNPS separation may be applied.
CARDINAL ALTITUDES- "Odd" or "Even" thousand-foot altitudes or flight levels;
e.g., 5,000, 6,000, 7,000, FL 250, FL 260, FL 270.
CARDINAL FLIGHT LEVELS- (See CARDINAL
ALTITUDES.)
CAT- (See CLEAR-AIR TURBULENCE.)
CDT PROGRAMS- (See CONTROLLED DEPARTURE TIME PROGRAMS.)
CEILING- The heights above the earth's surface of the lowest layer of clouds
or obscuring phenomena that is reported as "broken," "overcast," or
"obscuration," and not classified as "thin" or "partial."
CEILING [ICAO]- The height above the
ground or water of the base of the lowest layer of cloud below 6,000 meters
(20,000 feet) covering more than half the sky.
CENRAP- (See CENTER RADAR ARTS PRESENTATION/PROCESSING.)
CENRAP-PLUS- (See CENTER RADAR ARTS PRESENTATION/
PROCESSING-PLUS.)
CENTER- (See AIR ROUTE TRAFFIC CONTROL CENTER.)
CENTER'S AREA- The specified airspace within which an air route traffic
control center (ARTCC) provides air traffic control and advisory service.
(See AIR ROUTE TRAFFIC CONTROL CENTER.)
CENTER RADAR ARTS PRESENTATION/PROCESSING- A
computer program developed to provide a back-up system for airport surveillance
radar in the event of a failure or malfunction. The program uses air route
traffic control center radar for the processing and presentation of data on the
ARTS IIA or IIIA displays.
CENTER RADAR ARTS PRESENTATION/PROCESSING-PLUS- A computer program developed
to provide a back-up system for airport surveillance radar in the event of a
terminal secondary radar system failure. The program uses a combination of Air
Route Traffic Control Center Radar and terminal airport surveillance radar
primary targets displayed simultaneously for the processing and presentation of
data on the ARTS IIA or IIIA displays.
CENTER WEATHER ADVISORY- An unscheduled weather advisory issued by Center
Weather Service Unit meteorologists for ATC use to alert pilots of existing or
anticipated adverse weather conditions within the next 2 hours. A CWA may modify
or redefine a SIGMET.
CENTRAL EAST PACIFIC- An organized route system
between the U.S. West Coast and Hawaii.
CEP- (See CENTRAL EAST PACIFIC.)
CERAP- (See COMBINED CENTER-RAPCON.)
CFR- (See CALL FOR RELEASE.)
CHAFF- Thin, narrow metallic reflectors of various lengths and frequency
responses, used to reflect radar energy. These reflectors when dropped from
aircraft and allowed to drift downward result in large targets on the radar
display.
CHARTED VFR FLYWAYS- Charted VFR Flyways are flight paths recommended for use
to bypass areas heavily traversed by large turbine-powered aircraft. Pilot
compliance with recommended flyways and associated altitudes is strictly
voluntary. VFR Flyway Planning charts are published on the back of existing VFR
Terminal Area charts.
CHARTED VISUAL FLIGHT PROCEDURE APPROACH- An approach conducted while
operating on an instrument flight rules (IFR) flight plan which authorizes the
pilot of an aircraft to proceed visually and clear of clouds to the airport via
visual landmarks and other information depicted on a charted visual flight
procedure. This approach must be authorized and under the control of the
appropriate air traffic control facility. Weather minimums required are depicted
on the chart.
CHASE- An aircraft flown in proximity to another aircraft
normally to observe its performance during training or testing.
CHASE AIRCRAFT- (See CHASE.)
CIRCLE-TO-LAND MANEUVER- A maneuver initiated by the pilot to align the
aircraft with a runway for landing when a straight-in landing from an instrument
approach is not possible or is not desirable. This maneuver is made only after
ATC authorization has been obtained and the pilot has established required
visual reference to the airport.
CIRCLE TO RUNWAY (RUNWAY NUMBER)-
Used by ATC to inform the pilot that he must circle to land because the
runway in use is other than the runway aligned with the instrument approach
procedure. When the direction of the circling maneuver in relation to the
airport/runway is required, the controller will state the direction (eight
cardinal compass points) and specify a left or right downwind or base leg as
appropriate; e.g., "Cleared VOR Runway Three Six Approach circle to Runway Two
Two," or "Circle northwest of the airport for a right downwind to Runway Two
Two."
(See CIRCLE-TO-LAND MANEUVER.)
CIRCLING APPROACH- (See CIRCLE-TO-LAND MANEUVER.)
CIRCLING MANEUVER- (See CIRCLE-TO-LAND MANEUVER.)
CIRCLING MINIMA- (See LANDING MINIMUMS.)
CLASS A AIRSPACE- (SEE CONTROLLED AIRSPACE)
CLASS B AIRSPACE- (SEE CONTROLLED AIRSPACE)
CLASS C AIRSPACE- (SEE CONTROLLED AIRSPACE)
CLASS D AIRSPACE- (SEE CONTROLLED AIRSPACE)
CLASS E AIRSPACE- (SEE CONTROLLED AIRSPACE)
CLASS G AIRSPACE- That airspace not designated as Class A, B, C, D or E.
CLEAR-AIR TURBULENCE- Turbulence encountered in air where no clouds are
present. This term is commonly applied to high-level turbulence associated with
wind shear. CAT is often encountered in the vicinity of the jet stream.
CLEAR OF THE RUNWAY-
a. A taxiing aircraft, which is approaching a runway, is clear of
the runway when all parts of the aircraft are held short of the applicable
holding position marking.
b. A pilot or controller may consider an aircraft, which is exiting
or crossing a runway, to be clear of the runway when all parts of the aircraft
are beyond the runway edge and there is no ATC restriction to its continued
movement beyond the applicable holding position marking.
c. Pilots and controllers shall exercise good judgement to ensure
that adequate separation exists between all aircraft on runways and taxiways
at airports with inadequate runway edge lines or holding position
markings.
CLEARANCE- (See AIR TRAFFIC CLEARANCE.)
CLEARANCE LIMIT- The fix, point, or location to which an aircraft is cleared
when issued an air traffic clearance.
(See ICAO term CLEARANCE LIMIT.)
CLEARANCE LIMIT [ICAO]- The point
of which an aircraft is granted an air traffic control clearance.
CLEARANCE VOID IF NOT OFF BY (TIME)- Used by ATC to advise an
aircraft that the departure clearance is automatically canceled if takeoff is
not made prior to a specified time. The pilot must obtain a new clearance or
cancel his IFR flight plan if not off by the specified time.
(See ICAO term CLEARANCE VOID TIME.)
CLEARANCE VOID TIME [ICAO]- A
time specified by an air traffic control unit at which a clearance ceases to be
valid unless the aircraft concerned has already taken action to comply
therewith.
CLEARED AS FILED- Means the aircraft is cleared to proceed in
accordance with the route of flight filed in the flight plan. This clearance
does not include the altitude, DP, or DP Transition.
(See REQUEST FULL ROUTE CLEARANCE.)
CLEARED (Type Of) APPROACH- ATC
authorization for an aircraft to execute a specific instrument approach
procedure to an airport; e.g., "Cleared ILS Runway Three Six Approach."
(See INSTRUMENT APPROACH PROCEDURE.)
(See APPROACH CLEARANCE.)
CLEARED APPROACH- ATC
authorization for an aircraft to execute any standard or special instrument
approach procedure for that airport. Normally, an aircraft will be cleared for a
specific instrument approach procedure.
(See INSTRUMENT APPROACH PROCEDURE.)
(See CLEARED (TYPE OF) APPROACH.)
CLEARED FOR TAKEOFF- ATC
authorization for an aircraft to depart. It is predicated on known traffic and
known physical airport conditions.
CLEARED FOR THE OPTION- ATC authorization for an aircraft to
make a touch-and-go, low approach, missed approach, stop and go, or full stop
landing at the discretion of the pilot. It is normally used in training so that
an instructor can evaluate a student's performance under changing situations.
CLEARED THROUGH- ATC authorization
for an aircraft to make intermediate stops at specified airports without
refiling a flight plan while en route to the clearance limit.
CLEARED TO LAND- ATC authorization for an aircraft to land. It
is predicated on known traffic and known physical airport conditions.
CLEARWAY- An area beyond the takeoff runway under the control of airport
authorities within which terrain or fixed obstacles may not extend above
specified limits. These areas may be required for certain turbine-powered
operations and the size and upward slope of the clearway will differ depending
on when the aircraft was certificated.
CLIMBOUT- That portion of flight operation
between takeoff and the initial cruising altitude.
CLIMB TO VFR- ATC authorization for an aircraft to climb to VFR
conditions within Class B, C, D, and E surface areas when the only weather
limitation is restricted visibility. The aircraft must remain clear of clouds
while climbing to VFR.
CLOSE PARALLEL RUNWAYS- Two parallel runways whose
extended centerlines are separated by less than 4,300 feet, having a Precision
Runway Monitoring (PRM) system that permits simultaneous independent ILS
approaches.
CLOSED RUNWAY- A runway that is unusable for aircraft operations. Only the
airport management/military operations office can close a runway.
CLOSED TRAFFIC- Successive operations involving takeoffs and landings or low
approaches where the aircraft does not exit the traffic pattern.
CLT- (See CALCULATED LANDING TIME.)
CLUTTER- In radar operations, clutter refers to the reception and visual
display of radar returns caused by precipitation, chaff, terrain, numerous
aircraft targets, or other phenomena. Such returns may limit or preclude ATC
from providing services based on radar.
(See ICAO term Radar Clutter.)
CMNPS- (See CANADIAN MINIMUM
NAVIGATION PERFORMANCE SPECIFICATION AIRSPACE.)
COASTAL FIX- A navigation aid or intersection where an aircraft transitions
between the domestic route structure and the oceanic route structure.
CODES- The number assigned to a particular multiple pulse reply signal
transmitted by a transponder.
COMBINED CENTER-RAPCON- An air traffic
facility which combines the functions of an ARTCC and a radar approach control
facility.
(See AIR ROUTE TRAFFIC CONTROL CENTER.)
(See RADAR APPROACH CONTROL FACILITY.)
COMMON POINT- A significant
point over which two or more aircraft will report passing or have reported
passing before proceeding on the same or diverging tracks. To establish/maintain
longitudinal separation, a controller may determine a common point not
originally in the aircraft's flight plan and then clear the aircraft to fly over
the point. (See SIGNIFICANT POINT.)
COMMON PORTION- (See COMMON ROUTE.)
COMMON ROUTE- That segment of a North American Route between the inland
navigation facility and the coastal fix.
COMMON TRAFFIC ADVISORY FREQUENCY (CTAF)- A frequency designed for the
purpose of carrying out airport advisory practices while operating to or from an
airport without an operating control tower. The CTAF may be a UNICOM, Multicom,
FSS, or tower frequency and is identified in appropriate aeronautical
publications.
(Refer to AC 90-42, Traffic Advisory Practices at Airports Without
Operating Control Towers.)
COMPASS LOCATOR- A low power, low or medium
frequency (L/MF) radio beacon installed at the site of the outer or middle
marker of an instrument landing system (ILS). It can be used for navigation at
distances of approximately 15 miles or as authorized in the approach procedure.
a. Outer Compass Locator (LOM)- A compass locator installed at the
site of the outer marker of an instrument landing system.
b. Middle Compass Locator (LMM)- A compass locator installed at the
site of the middle marker of an instrument landing system.
COMPASS ROSE- A circle, graduated in
degrees, printed on some charts or marked on the ground at an airport. It is
used as a reference to either true or magnetic direction.
COMPOSITE FLIGHT PLAN- A flight plan which specifies VFR operation for one
portion of flight and IFR for another portion. It is used primarily in military
operations.
COMPOSITE ROUTE SYSTEM- An organized oceanic route
structure, incorporating reduced lateral spacing between routes, in which
composite separation is authorized.
COMPOSITE SEPARATION- A method of separating aircraft in a composite route
system where, by management of route and altitude assignments, a combination of
half the lateral minimum specified for the area concerned and half the vertical
minimum is applied.
COMPULSORY REPORTING POINTS- Reporting points which must be reported to ATC.
They are designated on aeronautical charts by solid triangles or filed in a
flight plan as fixes selected to define direct routes. These points are
geographical locations which are defined by navigation aids/fixes. Pilots should
discontinue position reporting over compulsory reporting points when informed by
ATC that their aircraft is in "radar contact."
CONFLICT ALERT- A function of certain air traffic control automated systems
designed to alert radar controllers to existing or pending situations between
tracked targets (known IFR or VFR aircraft) that require his/her immediate
attention/action.
(See MODE C INTRUDER ALERT.)
CONFLICT RESOLUTION- The resolution of
potential conflictions between aircraft that are radar identified and in
communication with ATC by ensuring that radar targets do not touch. Pertinent
traffic advisories shall be issued when this procedure is applied.
Note: This procedure shall not be provided utilizing mosaic radar systems.
CONSOLAN- A low frequency, long-distance NAVAID used principally for
transoceanic navigations.
CONTACT-
a. Establish communication with (followed by the name of the
facility and, if appropriate, the frequency to be used).
b. A flight condition wherein the pilot ascertains the attitude of
his aircraft and navigates by visual reference to the surface.
CONTACT APPROACH- An approach
wherein an aircraft on an IFR flight plan, having an air traffic control
authorization, operating clear of clouds with at least 1 mile flight visibility
and a reasonable expectation of continuing to the destination airport in those
conditions, may deviate from the instrument approach procedure and proceed to
the destination airport by visual reference to the surface. This approach will
only be authorized when requested by the pilot and the reported ground
visibility at the destination airport is at least 1 statute mile.
CONTAMINATED RUNWAY- A runway is considered
contaminated whenever standing water, ice, snow, slush, frost in any form, heavy
rubber, or other substances are present. A runway is contaminated with respect
to rubber deposits or other friction-degrading substances when the average
friction value for any 500-foot segment of the runway within the ALD fails below
the recommended minimum friction level and the average friction value in the
adjacent 500-foot segments falls below the maintenance planning friction level.
CONTERMINOUS U.S.- The 48 adjoining States and the District of Columbia.
CONTINENTAL UNITED STATES- The 49 States located on the continent of North
America and the District of Columbia.
CONTROL AREA [ICAO]- A controlled airspace extending upwards from a specified
limit above the earth.
CONTROLLED AIRSPACE- An airspace of defined dimensions within which air
traffic control service is provided to IFR flights and to VFR flights in
accordance with the airspace classification.
a. Controlled airspace is a generic term that covers Class A, Class
B, Class C, Class D, and Class E airspace.
b. Controlled airspace is also that airspace within which all
aircraft operators are subject to certain pilot qualifications, operating
rules, and equipment requirements in FAR Part 91 (for specific operating
requirements, please refer to FAR Part 91). For IFR operations in any class of
controlled airspace, a pilot must file an IFR flight plan and receive an
appropriate ATC clearance. Each Class B, Class C, and Class D airspace area
designated for an airport contains at least one primary airport around which
the airspace is designated (for specific designations and descriptions of the
airspace classes, please refer to FAR Part 71).
c. Controlled airspace in the United States is designated as
follows:
1. CLASS A- Generally, that airspace from 18,000 feet MSL up to
and including FL 600, including the airspace overlying the waters within 12
nautical miles of the coast of the 48 contiguous States and Alaska. Unless
otherwise authorized, all persons must operate their aircraft under
IFR.
2. CLASS B- Generally, that airspace from the surface to 10,000
feet MSL surrounding the nation's busiest airports in terms of airport
operations or passenger enplanements. The configuration of each Class B
airspace area is individually tailored and consists of a surface area and
two or more layers (some Class B airspaces areas resemble upside-down
wedding cakes), and is designed to contain all published instrument
procedures once an aircraft enters the airspace. An ATC clearance is
required for all aircraft to operate in the area, and all aircraft that are
so cleared receive separation services within the airspace. The cloud
clearance requirement for VFR operations is "clear of clouds."
3. CLASS C- Generally, that airspace from the surface to 4,000
feet above the airport elevation (charted in MSL) surrounding those airports
that have an operational control tower, are serviced by a radar approach
control, and that have a certain number of IFR operations or passenger
enplanements. Although the configuration of each Class C area is
individually tailored, the airspace usually consists of a surface area with
a 5 nautical mile (NM) radius, an outer circle with a 10NM radius that
extends from 1,200 feet to 4,000 feet above the airport elevation and an
outer area. Each person must establish two-way radio communications with the
ATC facility providing air traffic services prior to entering the airspace
and thereafter maintain those communications while within the airspace. VFR
aircraft are only separated from IFR aircraft within the airspace. (See
OUTER AREA)
4. CLASS D- Generally, that airspace from the surface to 2,500
feet above the airport elevation (charted in MSL) surrounding those airports
that have an operational control tower. The configuration of each Class D
airspace area is individually tailored and when instrument procedures are
published, the airspace will normally be designed to contain the procedures.
Arrival extensions for instrument approach procedures may be Class D or
Class E airspace. Unless otherwise authorized, each person must establish
two-way radio communications with the ATC facility providing air traffic
services prior to entering the airspace and thereafter maintain those
communications while in the airspace. No separation services are provided to
VFR aircraft.
5. CLASS E- Generally, if the airspace is not Class A, Class B,
Class C, or Class D, and it is controlled airspace, it is Class E airspace.
Class E airspace extends upward from either the surface or a designated
altitude to the overlying or adjacent controlled airspace. When designated
as a surface area, the airspace will be configured to contain all instrument
procedures. Also in this class are Federal airways, airspace beginning at
either 700 or 1,200 feet AGL used to transition to/from the terminal or en
route environment, en route domestic, and offshore airspace areas designated
below 18,000 feet MSL. Unless designated at a lower altitude, Class E
airspace begins at 14,500 MSL over the United States, including that
airspace overlying the waters within 12 nautical miles of the coast of the
48 contiguous States and Alaska, up to, but not including 18,000 feet MSL,
and the airspace above FL 600.
CONTROLLED AIRSPACE [ICAO]- An airspace
of defined dimensions within which air traffic control service is provided to
IFR flights and to VFR flights in accordance with the airspace classification.
(Note: Controlled airspace is a generic term which covers ATS airspace
Classes A, B, C, D, and E.)
CONTROLLED DEPARTURE TIME PROGRAMS- These programs are the flow control
process whereby aircraft are held on the ground at the departure airport when
delays are projected to occur in either the en route system or the terminal of
intended landing. The purpose of these programs is to reduce congestion in the
air traffic system or to limit the duration of airborne holding in the arrival
center or terminal area. A CDT is a specific departure slot shown on the flight
plan as an expected departure clearance time (EDCT).
CONTROLLED TIME OF ARRIVAL- The original estimated time of arrival adjusted
by the ATCSCC ground delay factor.
CONTROLLER- (See AIR TRAFFIC CONTROL SPECIALIST.)
CONTROLLER [ICAO]- A person authorized to provide air traffic control
services.
CONTROL SECTOR- An airspace area of defined horizontal and vertical
dimensions for which a controller or group of controllers has air traffic
control responsibility, normally within an air route traffic control center or
an approach control facility. Sectors are established based on predominant
traffic flows, altitude strata, and controller workload. Pilot-communications
during operations within a sector are normally maintained on discrete
frequencies assigned to the sector.
(See DISCRETE FREQUENCY.)
CONTROL SLASH- A radar beacon slash
representing the actual position of the associated aircraft. Normally, the
control slash is the one closest to the interrogating radar beacon site. When
ARTCC radar is operating in narrowband (digitized) mode, the control slash is
converted to a target symbol.
CONVECTIVE SIGMET- A weather advisory concerning convective
weather significant to the safety of all aircraft. Convective SIGMET's are
issued for tornadoes, lines of thunderstorms, embedded thunderstorms of any
intensity level, areas of thunderstorms greater than or equal to VIP level 4
with an area coverage of 4/10 (40%) or more, and hail 3/4 inch or greater.
CONVECTIVE SIGNIFICANT METEOROLOGICAL INFORMATION-
(See CONVECTIVE SIGMET.)
COORDINATES- The intersection of lines of reference, usually expressed in
degrees/minutes/seconds of latitude and longitude, used to determine position or
location.
COORDINATION FIX- The fix in relation to which facilities will handoff,
transfer control of an aircraft, or coordinate flight progress data. For
terminal facilities, it may also serve as a clearance for arriving aircraft.
COPTER- (See HELICOPTER.)
CORRECTION- An error has been made in the transmission and the correct
version follows.
COUPLED APPROACH- A coupled approach is an instrument approach performed by
the aircraft autopilot which is receiving position information and/or steering
commands from onboard navigation equipment. In general, coupled nonprecision
approaches must be discontinued and flown manually at altitudes lower than 50
feet below the minimum descent altitude, and coupled precision approaches must
be flown manually below 50 feet AGL.
Note: Coupled and autoland approaches are
flown in VFR and IFR. It is common for carriers to require their crews to fly
coupled approaches and autoland approaches (if certified) when the weather
conditions are less than approximately 4,000 RVR.
COURSE-
a. The intended direction of flight in the horizontal plane
measured in degrees from north.
b. The ILS localizer signal pattern usually specified as the front
course or the back course.
c. The intended track along a straight, curved, or segmented MLS
path.
(See INSTRUMENT LANDING SYSTEM.)
(See MICROWAVE LANDING SYSTEM.)
CPL [ICAO]- (See CURRENT FLIGHT
PLAN)
CRITICAL ENGINE- The engine which, upon failure, would most adversely affect
the performance or handling qualities of an aircraft.
CROSS (FIX) AT (ALTITUDE)- Used by ATC when a specific altitude
restriction at a specified fix is required.
CROSS (FIX) AT OR ABOVE (ALTITUDE)- Used by ATC when an
altitude restriction at a specified fix is required. It does not prohibit the
aircraft from crossing the fix at a higher altitude than specified; however, the
higher altitude may not be one that will violate a succeeding altitude
restriction or altitude assignment.
(See ALTITUDE RESTRICTION.)
CROSS (FIX) AT OR BELOW (ALTITUDE)-
Used by ATC when a maximum crossing altitude at a specific fix is
required. It does not prohibit the aircraft from crossing the fix at a lower
altitude; however, it must be at or above the minimum IFR altitude.
(See MINIMUM IFR ALTITUDES.)
(See ALTITUDE RESTRICTION.)
CROSSWIND-
a. When used concerning the traffic pattern, the word means
"crosswind leg."
b. When used concerning wind conditions, the word means a wind not
parallel to the runway or the path of an aircraft.
(See CROSSWIND COMPONENT.)
CROSSWIND COMPONENT- The wind component
measured in knots at 90 degrees to the longitudinal axis of the runway.
CRUISE- Used in an ATC clearance to authorize a pilot to
conduct flight at any altitude from the minimum IFR altitude up to and including
the altitude specified in the clearance. The pilot may level off at any
intermediate altitude within this block of airspace. Climb/descent within the
block is to be made at the discretion of the pilot. However, once the pilot
starts descent and verbally reports leaving an altitude in the block, he may not
return to that altitude without additional ATC clearance. Further, it is
approval for the pilot to proceed to and make an approach at destination airport
and can be used in conjunction with:
a. An airport clearance limit at locations with a standard/special
instrument approach procedure. The FAR's require that if an instrument letdown
to an airport is necessary, the pilot shall make the letdown in accordance
with a standard/special instrument approach procedure for that airport, or
b. An airport clearance limit at locations that are
within/below/outside controlled airspace and without a standard/special
instrument approach procedure. Such a clearance is NOT AUTHORIZATION for the
pilot to descend under IFR conditions below the applicable minimum IFR
altitude nor does it imply that ATC is exercising control over aircraft in
Class G airspace; however, it provides a means for the aircraft to proceed to
destination airport, descend, and land in accordance with applicable FAR's
governing VFR flight operations. Also, this provides search and rescue
protection until such time as the IFR flight plan is closed.
(See INSTRUMENT APPROACH PROCEDURE.)
CRUISING ALTITUDE- An altitude
or flight level maintained during en route level flight. This is a constant
altitude and should not be confused with a cruise clearance.
(See ICAO term CRUISING LEVEL.)
CRUISING LEVEL [ICAO]- A level
maintained during a significant portion of a flight.
CRUISE CLIMB- A climb technique employed by aircraft, usually at a constant
power setting, resulting in an increase of altitude as the aircraft weight
decreases.
CRUISING LEVEL- (See CRUISING ALTITUDE.)
CT MESSAGE- An EDCT time generated by the ATCSCC to regulate traffic at
arrival airports. Normally, a CT message is automatically transferred from the
Traffic Management System computer to the NAS en route computer and appears as
an EDCT. In the event of a communication failure between the TMS and the NAS,
the CT message can be manually entered by the TMC at the en route facility.
CTA- (See CONTROLLED TIME OF ARRIVAL.)
CTA- (See CONTROL AREA [ICAO].)
CTAF- (See COMMON TRAFFIC ADVISORY FREQUENCY.)
CURRENT FLIGHT PLAN [ICAO]- The flight plan, including changes, if any,
brought about by subsequent clearances.
CVFP APPROACH- (See CHARTED VISUAL FLIGHT PROCEDURE APPROACH.)
CWA- (See CENTER WEATHER ADVISORY and WEATHER ADVISORY.)