Kuwait DGCA ATPL Theory key terms

The minimum flight visibility and distance from cloud that allow a pilot to fly under visual flight rules. In Kuwait airspace these are set by DGCA regulation and vary with altitude and airspace class.

An explicit authorisation from ATC for an aircraft to operate within controlled airspace under specified conditions. Without it, entry is prohibited and the pilot commits a violation regardless of weather.

A clearance permitting flight in controlled airspace below visual meteorological conditions, subject to ATC approval and normally limited to staying clear of cloud and in sight of the surface.

A radio transmission giving an aircraft's identification, position, time, altitude and next reporting point. It lets ATC maintain separation when surveillance coverage is absent or degraded.

A ground radar that interrogates an aircraft transponder to obtain identity, pressure altitude and, with Mode S, selected level. It supplements primary radar and underpins modern ATC separation.

Airborne Collision Avoidance System, which interrogates nearby transponders and issues traffic advisories and resolution advisories. Pilots must follow a resolution advisory unless it endangers safety.

A proximity warning showing conflicting traffic that is not yet close enough to require manoeuvring. It prompts visual search and crew coordination but does not itself command a flight path change.

A mandatory instruction issued by the state of design and adopted by the operator's authority, requiring inspection, modification or limitation on an aircraft or component. Compliance is legally binding.

An approved document specifying which instruments and equipment may be inoperative for dispatch, with associated conditions and procedures. It allows safe operation without full technical dispatchability.

A certification, signed by authorised maintenance personnel, that specified work has been completed and the aircraft or component is fit for service. It must be issued before flight after maintenance.

A system that taps compressed air from the engine compressor stages to supply cabin pressurisation, air conditioning and anti-icing. Leaks can cause significant performance and safety consequences.

Equipment that prevents ice formation on critical surfaces, typically by heating with engine bleed air or electrical elements. It differs from de-icing, which removes ice already present.

The pressure difference between cabin and ambient atmosphere, kept within structural limits by outflow valves. Excessive differential or a rapid loss drives the need for oxygen and emergency descent.

The network of pressure sources and lines feeding airspeed, altimeter and vertical speed indicators. Blockages or leaks cause characteristic and potentially misleading instrument errors.

The reference pressure set on a barometric altimeter, such as QNH, QFE or standard pressure. Correct selection determines whether the instrument shows altitude, height or flight level.

The altitude at which pilots change from local pressure settings to standard pressure when climbing. It separates altitude references below from flight levels above and is published per aerodrome.

A surface of constant pressure referenced to standard pressure 1013.25 hPa, expressed in hundreds of feet. It provides common vertical separation for aircraft above the transition altitude.

The ratio of true airspeed to the local speed of sound. It governs compressibility effects, critical Mach limitations and high-altitude speed scheduling on jet aircraft.

The certified forward and aft limits within which an aircraft's centre of gravity must remain in all phases of flight. Loading outside these limits may make the aircraft uncontrollable.

The mass of an aircraft with structure, powerplant, fixed equipment and unusable fluids, excluding crew, payload and usable fuel. It is the starting point for all mass and balance calculations.

A document recording the aircraft's mass, centre of gravity position and distribution of traffic load before departure. It is signed by authorised personnel and confirms operation within limits.

The runway length required so that a failure at the critical engine failure speed allows either stopping or continuing the take-off within the available distance. It constrains maximum take-off mass.

The decision speed at which, following an engine failure, the take-off can be safely continued. Below it the take-off should be abandoned; it links performance planning to pilot action.

The distance needed to accelerate to V1, recognise an engine failure and bring the aircraft to a full stop. It must not exceed the available stopway or runway distance.

On a multi-engine propeller aircraft, the engine whose failure most adversely affects performance and control, usually due to asymmetric thrust and torque effects. It drives minimum control speeds.

The minimum fuel that must remain beyond trip fuel, covering contingency, alternate, final reserve and additional allowances. It protects against weather, routing and holding deviations.

A predetermined manoeuvre keeping an aircraft within a specified airspace while awaiting further clearance. Correct entry, timing and wind correction are essential to remain within protected airspace.

The period after loss of oxygen during which a person can still take effective corrective action. It shortens rapidly with increasing altitude and underpins hypoxia training.

A deficiency of oxygen reaching body tissues, causing impaired judgement, euphoria and eventual unconsciousness. Recognising subtle early symptoms is difficult without training or oxygen monitoring.

A false perception of position or motion relative to the earth, typically when visual references are lost. Pilots must rely on instruments rather than sensations to recover.

The altimeter setting that makes the instrument read aerodrome elevation when on the ground. It provides altitude above mean sea level and is standard below the transition altitude.

A meteorological warning of hazardous conditions such as severe turbulence, icing or volcanic ash affecting a defined area. It is issued for the safety of en-route aircraft.

A rapid change in wind speed or direction over a short distance, often near thunderstorms or fronts. It can cause sudden airspeed and lift changes close to the ground.

The shortest path between two points on the earth's surface, lying on a plane through the earth's centre. It is the basis for long-range track planning and rhumb line comparison.

A track crossing every meridian at the same angle, appearing as a straight line on a Mercator chart. It is simpler to fly but longer than a great circle.

The angular difference between true north and magnetic north at a location, changing slowly over time. It must be applied to convert between true and magnetic headings and bearings.

A rapid, usually controlled, descent to a lower altitude, typically after cabin depressurisation. It requires prompt oxygen use, ATC notification and terrain clearance awareness.

The angle between the wing chord line and the relative airflow. Increasing it raises lift until the critical angle, beyond which the wing stalls.

The angle of attack at which airflow separates from the wing and lift decreases sharply. A stall always occurs at this angle regardless of speed, mass or attitude.

The ratio of total lift to aircraft weight, expressed in g. It increases in turns and manoeuvres, raising stall speed and structural loads.

The obligation to repeat back safety-related ATC clearances and instructions, such as route, altitude and frequency. It confirms the message was correctly received and understood.

The agreed set of words and phrases used in radiotelephony to avoid ambiguity. It is mandatory where prescribed and reduces misunderstanding in busy or noisy environments.