Coverage„ noun 1. the amount of space or time given to a subject, an event, etc.More complete coverage of the one-in-sixty rule is given in the plotting section of these notes. 2. the area within which a radar unit can detect objects o glidepath coverage o localiser coverage
cowlnoun a covering usually made up of hinged or removable panels □ cowl flap a removable or hinged panel of a cowl o Further cooling can be obtained by the use of controllable cowl flaps which regulate the amount of air flowing across the cylinders.
CPL abbreviation Commercial Pilot’s Licence
crabnoun a manoeuvre in which an aircraft is steered slightly into a crosswind to compensate for flying slightly off course ■ verb to steer an aircraft slightly into a crosswind to compensate for flying slightly off course craftnoun 1. a boat, etc., for carrying people or goods on water 2. an aircraft or spacecraft for carrying people or goods in the air or in space o An airship is classified as a lighter-than-air craft.
crankshaftnoun the part of a piston engine connecting the pistons, via the connecting rods, to the flywheel and gearbox o Rpm is the number of revolutions per minute that the engine crankshaft is making. crashnoun an accident that causes damage ■ verb to have an accident or collision that causes damage o The aircraft crashed into the sea.
land heavily without using the undercarriage, so that the aircraft is damaged o The aircraft crash-landed short of the runway.
creepnoun 1. a process of weakening and slow damage to something o Creep is a particular feature of components which are subjected to operation at high temperatures. 2. a slight movement of a tyre on a wheel caused by landing o Aligned white marks on the wheel and tyre indicate that there is no creep.
criticaladjective 1.extremely important, essential o Temperature and oil pressure are critical to any type of system. 2. at which an important change occurs o As the angle of attack is increased, it reaches the critical point when the airflow over the upper surface of the wing begins to break down.
crossverb 1. to get from one side of an area to another □ to cross the Atlantic to go from one side of the Atlantic to the other 2. to go across each other at an angle o Meridians intersect at the poles and cross the equator at right angles.
cross-checknoun verification, making certain ■ verb to verify or make certain o Cross-check doors closed and locked and escape slides armed. (note: This word is often used in brief messages from one crew member to another, as from the pilot to cabin staff, to confirm that an action has been carried out.)
crosswindnoun a surface wind which blows at an angle to the landing or take-off heading o On some aircraft, crosswind take-offs should be made with full aileron deflection in the direction from which the wind is blowing.
Comment: A crosswind landing is one of the most difficult exercises for a student pilot. The final approach is usually made with the aircraft yawed into wind, while tracking the extended runway centreline. Just before touchdown, the pilot aligns the aircraft with the direction of flight using the rudder pedals. Correct timing for the alignment and accurate airspeed are required to achieve positive contact with the runway surface otherwise the aircraft may depart the runway to one side.
crosswind componentnoun that part of the wind force acting at an angle to the direction of flight crosswind legnoun part of the airfield traffic circuit flown at approximately 90° to the direction of take off and climb out, followed by the downwind leg CRT ,abbreviation cathode ray tube
cruisenoun the main part of the flight between top of climb after take-off and descent for landing ■ verb to fly the main part of the flight between top of climb after take-off and descent for landing o We are cruising at 500 kt. o Cruising speed, cruising power and cruising altitude are selected to give maximum engine efficiency and prolong engine life.
cruising weightnoun the weight of an aircraft in flight, consisting of its weight when empty, the weight of its payload, and the weight of the fuel that it has left crushverb to damage by pressure o Excessive load on the beam may crush the core.
CSDU abbreviation constant speed drive unit
CSU abbreviation constant speed unit CTA abbreviation control area CTOT abbreviation calculated take-off time
cubicadjective measured in volume, by multiplying length, depth and width □ cubic centimetres (cc) the usual unit used to measure the capacity of an internal-combustion engine o The engine has a capacity of 2,000cc. Abbreviation cc □ cubic foot, cubic inch, cubic metre, cubic yard the volume of a cube whose edge measures one foot, inch, metre or yard, respectively
of thermal activity resulting from the warming of the surface. o Grey cumulus often develop into cumulonimbus. i> altocumulus, stratocumulus cumulus cloudnoun clouds which form only in an unstable atmosphere and, as the name suggests, often build vertically for great distances. Also called heap cloud current‘ adjective present,actual, happening at the moment □ current weather conditions present weather conditions □ current position the position now ■ noun 1. an electrical supply o alternating current o direct current 2. flow
curvaturenoun a curved shape □ curvature of the earth the curving of the Earth’s surface due to the spherical form of the Earth customaryadjective normal or usual o It is customary for the senior cabin supervisor to introduce herself to passengers at the start of a flight.
customsnoun an official department of government concerned with movement of people and freight across national borders □ customs aerodrome an aerodrome, usually near a border or coast, with customs facilities
customs dutynoun same as import duty o the duty payable on a carton of cigarettes cyclenoun a series of actions which end at the same point as they begin o With the piston engine, the cycle is intermittent, whereas in the gas turbine, each process is continuous. □ life cycle of the thunderstorm cell the process of formation, development and decay of a thunderstorm
cyclonenoun a system of winds rotating inwards to an area of low barometric pressure o These areas of low pressure are called hurricanes in the Atlantic Ocean, cyclones in the Indian Ocean and Bay of Bengal, and typhoons in the China Sea. Also called low, depression
cyclonicadjective referring to air movement, which turns in the same direction as the Earth and which, when seen from above, is anticlockwise in the northern hemisphere and clockwise in the southern hemisphere o In winter the sub-tropical high retreats and gives way to cyclonic pressure patterns which produce cool unsettled conditions with rain at times.
cylindernoun a device shaped like a tube, in which a piston moves o Smaller aircraft have a static hydraulic system similar to a car, with a master cylinder and individual brake cylinders at each wheel. □ cylinder block the casing containing the cylinders in a internal combustion engine □ cylinder head the removable top part of a piston engine cylinder containing plugs, inlet and exhaust connections and valves
D abbreviation danger area DA abbreviation danger area DAAIS abbreviation danger area activity information service DACS abbreviation danger area crossing service
DADC abbreviation digital air data computer
DADS abbreviation digital air data system
DALR abbreviation dry adiabatic lapse rate
damagenoun harm that is caused to something o If the temperature rises it can cause serious damage to the engine. ■ verb to cause harm to something o Small stones around the run-up area may damage propellers.
damage tolerancenoun the ability of a material or structure to withstand or resist damage o The structural efficiency of bonded and machined structure is not achieved at the expense of damage tolerance.
dampenverb 1. to decrease or reduce o An accumulator is fitted to store hydraulic fluid under pressure and dampen pressure fluctuations. 2. to make slightly wet dampernoun a device to decrease or reduce something o A yaw damper is usedfor rudder control. D & D abbreviation distress and diversion cell
Abbreviation D, DA
danger zonenoun an area where danger exists datanoun 1. information made up of numbers, characters and symbols often stored on a computer in such a way that it can be processed o Airspeed information is supplied from an air data computer. □ meteorological data information about weather conditions stored on a computer 2. information. t> recorder
datumnoun a reference or base point of a scale or measurement, e.g. mean sea level datum shift trim systemnoun a trim system which varies the incidence of an all-moving tailplane without moving the cockpit controls o In some aircraft, the datum shift is operated automatically. dB abbreviation decibel DC abbreviation direct current