Aviation Dictionary

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Aviation Dictionary: C

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CAAP Civil Aviation Advisory Publication
Callsign A combination of either letters or numbers used to identify an aircraft.Normally, the callsign can be seen on the side or tail of the aircraft.
Camber The curve of an aerofoil (wing) from the leading edge to the trailing edge
CAO Civil Aviation Orders include information on technical standards and specifications and are administered by CASA (Civil Aviation Authority) Australia.
Carburetor A component that mixes the air and fuel ratio which then flows to the engine. Carburetors are normally found in older models piston aircraft and newer models generally have a fuel injection system.
CAS Calibrated Air speed
CASA the Civil Aviation Authority of Australia 
CASR 1998 Civil Aviation Safety Regulations 1998
CAT Clear air turbulence
CAVOK Cloud and visibility OK. Visibility 10km or greater and no significant weather
CB Cumulonimbus
CBT Computer-based test
CDFA Continuous descent flight angle
CDI Course deviation indicator
CDP Climb descent procedure
Centre of Gravity (CoG) Is the position on the aircraft where it would balance on a point if it was possible to be suspended at that point. This is calculated by supporting the aircraft on a set of scales and noting the weights shown on each set.
Chart Symbols Symbols found on an aeronautical chart (map)
CHT Cylinder head temperature
Circuit A set pattern flown around a runway, Circuits can be both left hand or right hand, depending on the aerodrome layout and wind direction.
Chord Line An imaginary line drawn from the trailing edge to the leading edge of an aerofoil.
Clearance Obtaining permission to enter controlled airspace from ATC.
Class G Uncontrolled Airspace - no clearances required and no control towers.
Climb A procedure that will cause an intentional gain in altitude usually at a planned rate of climb.
Climb ut - A phase of flight shortly after take-off during which you would retract flaps and gear.
Clock Code A way of identifying the position of yourself or someone else based on the hour positions of a clock. Eg: 12 o’clock will be directly in front of you, 3 o’clock will be 90 degrees to your right. We can also add in high or low to the position, so 12 o’clock high would mean that the other aircraft is directly in front of you, as well as above your altitude. 12 o’clock low would be in front of your position as well as below your altitude.
C of A Certificate of Airworthiness  
Commercial Pilot Licence (CPL) You are a professional pilot and may be paid and will have a minimum 200-250 hours training.  Can be VFR or IFR, choose twin or single engine aircraft, but must be rated in a complex aircraft with Variable Pitch and retractable endorsement (in Australia)
Common Frequency Zones (CFZ) An airspace area which uses the same frequency. Position reports are not mandatory, but it is still good practice to make continual position calls
Communicate Making contact over the radio to other aircraft or ATC.
Compass A device that has a magnetic needle which will point to Magnetic North. In aircraft, a compass can experience variations due to interference from the electrical system and other components within the aircraft and a deviation card can be found which will give the correction for any errors. In the Southern Hemisphere, ONUS is used for compass turns, ONUS being : Overturn North Underturn South
Constant Speed Propeller (CSU) Also known as a variable pitch propeller. The pitch of the propeller blade is able to be changed according to the phase of flight, in order to achieve the most efficiency from the propeller. A fine pitch (high rpm) is used during a take-off while a coarse pitch (low rpm) is used during cruise.
Controlled Airspace The area that requires permission for entry or exit from ATC. Any requests must be made towards ATC for any change to the direction of flight or current altitude. Any instructions issued by ATC must be followed as long as it is safe to do so and by following any instructions, will not break any laws. A pilot can deny a given instruction if he is unable to fulfil the request and may suggest another option that might work for ATC as well.
Convective Turbulence This is low altitude turbulence caused by the sun heating up the earths’ surface. As air moves over a warm surface, it heats up and rises, causing convective currents. Not all air will heat up and rise in a constant manner, and this creates differences in the direction of movement of the air and when flown through, we experience these differences as turbulence.
CP Critical point
CPL Commercial Pilot Licence
CRM Crew resource management
Cross ountry flight - A flight that extends further than 50 nm from the origin airport and may include a landing at a different airport. Can also be referred to as a Nav Flight.
Crosswind This is  a direction of wind that is blowing from any direction other than directly in front of, or directly behind you. With any crosswind in flight, a certain amount of drift needs to be maintained in order for the aircraft to fly in the intended direction.
Crosswind Circuit A circuit flown where the wind is not in line with the runway vector. At some aerodromes with more than one runway, a crosswind circuit may be flown intentionally for practice purposes.
Cruise The phase of flight where the aircraft levels off after a climb, and flies at a level altitude until required to descend to land.
CSU Constant Speed unit
CTA Controlled Airspace
CTAF Common Traffic Advisory Frequency
CTR Control Zone
Cumulonimbus Clouds Formed by powerful updraughts, creating a large, vertical cloud. Associated with large downpours, thunderstorms and hail. The can be formed along frontal lines or anywhere where a significant updraught is formed.
Cumulus Clouds The cotton , puffy clouds generally seen on a fair weather day. These can form into cumulonimbus clouds.
CVR Cockpit voice recorder

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