Pilot/Controller Glossary

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.
(Refer to 14 CFR Part 1.)

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.
(See SPECIAL VFR CONDITIONS.)
(Refer to AIM.)

CLOSED TRAFFIC- Successive operations involving takeoffs and landings or low approaches where
the aircraft does not exit the traffic pattern.
CLOUD- A cloud is a visible accumulation of
minute water droplets and/or ice particles in the
atmosphere above the Earth"s surface. Cloud differs
from ground fog, fog, or ice fog only in that the latter
are, by definition, in contact with the Earth"s surface.
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.

CHAFF.)
GROUND CLUTTER.)
PRECIPITATION.)
TARGET.)
ICAO term RADAR CLUTTER.)

CMNPS-
(See CANADIAN MINIMUM NAVIGATION
PERFORMANCE SPECIFICATION AIRSPACE.)

CLIMBOUT- That portion of flight operation
between takeoff and the initial cruising altitude.

COASTAL FIX- A navigation aid or intersection
where an aircraft transitions between the domestic
route structure and the oceanic route structure.

CLIMB VIA" An abbreviated ATC clearance that
requires compliance with the procedure lateral path,
associated speed restrictions, and altitude restrictions
along the cleared route or procedure.

CODES- The number assigned to a particular
multiple pulse reply signal transmitted by a
transponder.

CLOSE PARALLEL RUNWAYS- Two parallel
runways whose extended centerlines are separated by
less than 4,300 feet and at least 3000 feet (750 feet for
SOIA operations) for which ATC is authorized to
conduct simultaneous independent approach operations. PRM and simultaneous close parallel appear in
approach title. Dual communications, special pilot
training, an Attention All Users Page (AAUP), NTZ
monitoring by displays that have aural and visual
alerting algorithms are required. A high update rate
surveillance sensor is required for certain runway or
approach course spacing.

COLD TEMPERATURE COMPENSATION- An
action on the part of the pilot to adjust an aircraft"s
indicated altitude due to the effect of cold
temperatures on true altitude above terrain versus
aircraft indicated altitude. The amount of
compensation required increases at a greater rate with
a decrease in temperature and increase in height
above the reporting station.

CLOSED RUNWAY- A runway that is unusable for
aircraft operations. Only the airport management/
military operations office can close a runway.

(See DISCRETE CODE.)

COLLABORATIVE TRAJECTORY OPTIONS
PROGRAM (CTOP)- CTOP is a traffic management
program administered by the Air Traffic Control
System Command Center (ATCSCC) that manages
demand through constrained airspace, while considering operator preference with regard to both route
and delay as defined in a Trajectory Options Set
(TOS).