A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Cancelled - the emergency condition not exist any more

Ceiling - The height above the ground or water of the base of the lowest layer of cloud below 6000 metres (20 000 feet) covering more than half the sky.

Ceiling minimum -

Centerline lights - RCLS - lights embedded into the surface of the runway at 50 ft (15 m) intervals along the runway centerline on some precision

instrument runways. White except the last 900 m (3,000 ft): alternate white and red for next 600 m (1,969 ft) and red for last 300 m (984 ft).

Circle to land maneuver - 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.

Circling landing minimum - A statement of MDA (Minimum decent altitude) and visibility required for the circle-to-land maneuver.

Clearance - Air traffic clearance - An authorization by air traffic control for the purpose of preventing collision between known aircraft, for an aircraft

to proceed under specified traffic conditions within controlled airspace.

Clearance limit - The fix, point, or location to which an aircraft is cleared when issued an air traffic clearance.

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.

cloud break procedure - A cloud break procedure may be approved by the Commissioner for Civil Aviation when one or more of the following

conditions apply:

Such procedure is conducted outside controlled airspace.

Such procedure is conducted inside controlled airspace.

The runway and/or equipment does not comply with ICAO requirements for instruments approach procedure.

The runway is not aligned with the final approach track.

local QNH may not be available.

Any cloud break procedure outside controlled airspace is conducted at the discretion of the pilot in command.

In the event that such runway and/or equipment do not comply with ICAO requirements the OCA/H will not be lower than that specified for circling

minima as applicable to the respective aircraft category.

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".

Control area - A controlled airspace extending upward from specified limit above the earth.

Controlled aerodrome - An aerodrome for which air-traffic control facilities are provided.

controlled airspace - An airspace defined dimensions within which air traffic control service is provided to IFR flights in accordance with the

airspace classification.

Control zone - CTR or controlled traffic region - A controlled airspace extended upward from the surface of the earth to a specified upper limit.

Course - The intended direction of flight, in the horizontal plane, measured in degrees, from north.

Cruising level - A level maintained during a significant portion of a flight.