Kuwait DGCA CPL Theory key terms

Weather conditions in which flight visibility, distance from cloud, and ceiling equal or exceed the minima set for the airspace class, allowing the pilot to see and avoid other traffic and terrain.

Conditions below the prescribed visual meteorological minima, in which flight must be conducted under instrument flight rules and separation is normally provided by ATC.

Cruising level rule assigning magnetic tracks from 000 to 179 degrees to odd thousands of feet and tracks from 180 to 359 degrees to even thousands, with 500-foot offsets where required.

The altitude at or below which the aircraft's altimeter is set to local pressure (QNH); above it the standard pressure setting is used. It is published for each aerodrome or area.

The lowest flight level available for use above the transition altitude, chosen so that adequate vertical separation exists between aircraft using QNH and those using standard pressure.

Airspace of defined dimensions within which air traffic control service is provided to IFR flights and, in some classes, to VFR flights, requiring an ATC clearance for entry.

An authorisation for an aircraft to proceed under conditions specified by an air traffic control unit, which does not by itself relieve the pilot of responsibility for terrain and traffic avoidance.

The obligation of a pilot to repeat back safety-related ATC instructions and clearances, such as route, level, heading and frequency items, so that the controller can verify correct reception.

The maximum speed at which full, abrupt control deflection can be applied without exceeding the design limit load factor; it decreases with reducing mass because it scales with the square root of the load factor ratio.

The maximum load that an aircraft structure is designed to withstand in normal operation without permanent deformation; the ultimate load is this value multiplied by the design safety factor of 1.5.

The ratio of the total lift produced to the aircraft's weight, expressed in g. It increases in turns and pull-ups and determines the structural stress imposed on the airframe.

An ignition system with two independent magnetos, each firing one of two spark plugs per cylinder, providing redundancy and more complete combustion for improved performance and reliability.

A pre-flight engine run-up test in which each magneto is selected in turn to confirm the engine keeps running and that the drop in RPM stays within the manufacturer's stated limits.

Ice formation in the carburettor venturi caused by fuel vaporisation and pressure drop cooling, which can occur at outside air temperatures well above freezing and progressively reduces engine power.

A pilot-controlled system that routes heated air into the carburettor to melt or prevent ice; applying it enriches the mixture and typically causes a small RPM drop.

The pressure-sensing installation comprising a forward-facing pitot tube for total pressure and static ports for ambient pressure, supplying the airspeed indicator, altimeter and vertical speed indicator.

A blockage of the pitot head, often by ice or insects, that traps pressure in the airspeed indicator so it behaves like an altimeter: it over-reads in a climb and under-reads in a descent.

A selectable cabin or alternate port used when the normal static source is blocked, restoring approximate pressure sensing at the cost of small errors in airspeed, altitude and vertical speed readings.

The pressure reference dialled into the altimeter: QNH gives altitude above mean sea level, QFE gives height above a reference datum, and 1013.2 hPa gives flight levels.

The altimeter subscale setting that, when applied at aerodrome elevation, makes the altimeter indicate elevation above mean sea level; it is derived from station pressure reduced to sea level.

The point through which the total weight of the aircraft acts; its position along the longitudinal axis must remain within the certified forward and aft limits for controllability and stability.

The certified region on a mass-versus-CG chart within which the loaded aircraft must remain for all phases of flight, bounded by forward and aft CG limits and by maximum mass.

The horizontal distance from the reference datum to a mass item; multiplying each mass by its arm and summing the products gives the total moment used to locate the centre of gravity.

The mass of the aircraft as delivered plus unusable fuel, full operating fluids, and standard equipment, excluding crew, passengers, usable fuel and payload; it is the starting point of the load sheet.

The highest mass at which the aircraft is certified to commence the take-off run; it may be limited by structure, field length, obstacle clearance, climb performance or tyre speed.

The pressure altitude corrected for temperature deviation from ISA; high density altitude reduces air density and therefore engine power, propeller thrust and lift, lengthening take-off and landing distances.

The altitude indicated when the altimeter subscale is set to the standard pressure 1013.2 hPa; it is the reference used for aircraft performance charts and flight levels.

A surface of constant pressure referenced to 1013.2 hPa and separated from other such surfaces by stated pressure intervals, expressed in hundreds of feet and used above the transition altitude.

Carrying more fuel than required for a sector in order to buy it where it is cheaper, weighed against the extra fuel burned to carry that additional mass.

The furthest point along a route from which the aircraft can return to the departure aerodrome with the fuel remaining, allowing for the planned diversion and reserves.

The point along a route at which the time to reach either of two nominated aerodromes is equal, used to select the most suitable diversion in an emergency.

The fuel required to hold for a specified period, commonly 30 minutes at 1,500 feet above the alternate aerodrome in piston aircraft, which must remain at landing.

A condition in which the tissues receive insufficient oxygen; symptoms such as euphoria, impaired judgement and tingling are insidious, and the time of useful consciousness falls with increasing altitude.

The period after loss of normal oxygen supply during which a person can still take effective corrective action; it shortens rapidly as cabin altitude increases above about 10,000 feet.

Abnormally rapid or deep breathing that lowers blood carbon dioxide, producing dizziness, tingling and visual disturbance that can be mistaken for hypoxia; treatment is to slow the breathing rate.

A mistaken perception of the aircraft's position or motion relative to the earth, typically arising when visual references are lost and the pilot misinterprets vestibular sensations such as the somatogravic illusion.

A false sensation of pitching up during strong linear acceleration, often in the take-off or go-around, which may lead a pilot to push the nose down when no actual climb has occurred.

The altimeter subscale setting that makes the altimeter read zero at a specified reference point, usually aerodrome elevation, so the instrument indicates height above that point.

A reference atmosphere with sea-level temperature 15 degrees Celsius, pressure 1013.25 hPa and a lapse rate of about 1.98 degrees Celsius per 1,000 feet up to the tropopause, used for performance and calibration.

The leading edge of advancing cold air that undercuts warm air, producing rapid lifting, cumulonimbus cloud, heavy showers, squall lines and marked wind shifts with a sharp temperature fall.

The boundary where advancing warm air rides over colder air, giving a gradual slope, extensive stratiform cloud, steady precipitation and reduced visibility over a wide area.

A line of active thunderstorms, often ahead of a cold front, producing severe turbulence, strong gusty winds, heavy rain and possibly hail along a narrow, fast-moving band.

A change of wind speed or direction over a short distance, horizontally or vertically; low-level shear on approach can cause sudden airspeed loss and requires an immediate go-around.

A small, intense downdraught that spreads out at the surface, producing a headwind then tailwind change over a short distance and potentially causing a severe performance loss near the ground.

The angular difference at a given place between true north and magnetic north, east or west, which must be applied when converting between true and magnetic directions on a chart.

The error of a magnetic compass caused by the aircraft's own magnetic fields, varying with heading and corrected by a compass swing and a deviation card.

A line on a chart joining places of equal magnetic variation; the agonic line is the isogonal of zero variation where true and magnetic north coincide.

The magnetic bearing from a VOR station to the aircraft's position, displayed by the course deviation indicator; tracking inbound means flying the reciprocal of the selected radial.

The display element of a VOR or ILS receiver showing the selected course and the aircraft's lateral displacement from it, with full-scale deflection representing a defined angular or linear offset.

The vertical guidance beam of an ILS, typically set at about 3 degrees, giving the pilot a fly-up or fly-down indication to follow the correct descent path to the runway.

The altitude on a precision approach at which a missed approach must be initiated if the required visual reference has not been established; it is referenced to the altimeter with QNH set.

A standard manoeuvre abandoning the approach and climb-out, applied when the approach is unstable, the runway is not assured, or an instruction to discontinue the approach is received.

An approach in which the pilot keeps the aerodrome or preceding traffic in sight and is cleared to proceed visually, remaining responsible for separation from traffic and terrain.

The angle between the wing chord line and the relative airflow; increasing it raises lift up to the critical value, beyond which the wing stalls regardless of airspeed or attitude.

The angle of attack at which the airflow separates from the wing and lift reaches its maximum; exceeding it causes a stall, which can occur at any speed or attitude.

A loss of lift caused by airflow separation when the critical angle of attack is exceeded, indicated by buffet, a sinking sensation and often a warning horn before full separation.

The rearward component of lift resulting from wingtip vortices; it increases with the square of the lift coefficient and is greatest at low speed and high angle of attack.

The reduction in induced drag and downwash when flying within about one wingspan of the ground, allowing the aircraft to float during landing and to lift off below normal flying speed.

The document recording the aircraft's mass and centre of gravity for a flight, signed by the responsible person, confirming the figures lie within the certified limits.