GCAA CPL Theory Exam (UAE) key terms

Visual Flight Rules: a set of regulations allowing a pilot to operate an aircraft primarily by looking outside the cockpit, provided specified weather minima and cloud-clearance criteria are met.

Instrument Meteorological Conditions: weather conditions below the minimum visibility or cloud-clearance values for visual flight, requiring the flight to be conducted under instrument flight rules.

An authorisation issued by air traffic control permitting a flight to operate within a control zone in weather below normal visual minima, subject to pilot request and specified conditions.

Controlled airspace extending upwards from the surface to a specified upper limit around an aerodrome, within which all flights require an air traffic control clearance.

An authorisation for an aircraft to proceed under conditions specified by an air traffic control unit, which the pilot must comply with unless safety requires otherwise.

The mandatory verbal repetition by a pilot of safety-related clearance elements, allowing the controller to verify that the instruction has been correctly received and understood.

The acute angle between an aerofoil's chord line and the relative airflow approaching it; increasing this angle raises lift up to the critical value where the airflow separates.

The angle of attack at which an aerofoil produces maximum lift and beyond which the airflow separates from the upper surface, causing a stall regardless of airspeed or attitude.

A condition in which the wing exceeds its critical angle of attack, the airflow separates, lift reduces sharply and control effectiveness is impaired until the angle is reduced.

The ratio of the total aerodynamic force acting on an aircraft to its weight; it increases in turns and manoeuvres, raising the speed at which the wing stalls.

The angle between an aircraft's lateral axis and the horizontal; increasing bank steepens the turn and raises both load factor and stall speed.

The speed at which an aircraft changes heading, usually expressed in degrees per second; at a given airspeed it depends on bank angle.

A turn performed at three degrees per second, completing 360 degrees in two minutes, used for instrument flying and procedure turns.

The point at which the aircraft's total weight is considered to act; its position must remain within specified forward and aft limits for safe controllability and stability.

The calculation and control of an aircraft's weight and centre of gravity position to ensure they stay within certified limits for the intended flight.

The horizontal distance from a reference datum to an item's centre of gravity; multiplying it by the item's mass gives the moment used in balance calculations.

The altitude in the standard atmosphere at which the prevailing air density would occur; high temperature, low pressure or high humidity raise it and degrade performance.

The altitude indicated when the altimeter subscale is set to the standard pressure of 1013.25 hectopascals, used for flight levels and performance calculations.

The altitude above an aerodrome at which pilots change the altimeter subscale from local pressure to standard pressure and thereafter report flight levels.

A surface of constant atmospheric pressure related to the standard datum of 1013.25 hectopascals, expressed in hundreds of feet and used above the transition altitude.

The horizontal distance required from the start of the take-off roll to reaching a specified height above the runway, corrected for mass, wind, temperature and pressure.

A condition in which body tissues receive insufficient oxygen; in aviation it commonly results from high altitude and impairs judgement and vision before the pilot notices symptoms.

The period after loss of oxygen supply during which a person can still perform useful, purposeful actions before becoming incapacitated.

Abnormally rapid or deep breathing that lowers blood carbon dioxide, causing dizziness, tingling and confusion that can be mistaken for hypoxia.

A pilot's mistaken perception of the aircraft's position or motion relative to the earth, often caused by conflicting or absent visual cues in poor visibility.

A false sensation of pitching up or down caused by linear acceleration or deceleration, which may lead a pilot to push or pull the control column incorrectly.

The altimeter subscale setting that, when applied at aerodrome elevation, causes the altimeter to indicate elevation above mean sea level.

The altimeter subscale setting that causes the altimeter to read zero on the aerodrome, indicating height above that aerodrome rather than altitude above sea level.

A line drawn on a weather chart joining places of equal atmospheric pressure, whose spacing indicates the strength of the pressure gradient and hence surface wind speed.

The apparent deflection of moving air caused by the earth's rotation, turning wind to the right in the northern hemisphere and to the left in the southern hemisphere.

A direction measured clockwise from true north to a line joining two points, used with charts and unaffected by magnetic variation.

The angular difference at a given place between true north and magnetic north, applied to convert true bearings into magnetic bearings and vice versa.

The direction in which an aircraft's longitudinal axis points, expressed in degrees from a chosen north reference and distinct from the actual track made good.

The actual path of an aircraft over the ground, expressed as a direction from a north reference; it differs from heading when wind causes drift.

The angular difference between an aircraft's heading and the track it actually makes good over the ground, produced by the crosswind component.

VHF Omnidirectional Range: a ground beacon transmitting signals that allow an equipped aircraft to determine the magnetic bearing of the aircraft from the station.

A magnetic bearing from a VOR station, expressed in degrees; an aircraft flying along a given radial is positioned on that line from the beacon.

A four-digit octal code selected in the aircraft transponder, enabling air traffic control to identify the aircraft on radar displays.

A radar system in which ground interrogators trigger aircraft transponders to reply with identification and altitude information, supplementing primary radar returns.