Kuwait DGCA PPL Theory key terms

A mandatory notice issued by the state of registry requiring inspection, modification, or repair of an aircraft, engine, or component to correct an unsafe condition. Compliance is compulsory and must be recorded in the aircraft logbooks.

A document confirming that an aircraft conforms to its approved type design and is safe to operate. It is issued or validated by the state of registry and remains valid only while maintenance and airworthiness requirements are met.

The set of processes, inspections, and records that keep an aircraft in a condition compliant with its type design throughout its service life. It includes scheduled maintenance, defect rectification, and compliance with mandatory instructions.

Controlled airspace in which both IFR and VFR flights are permitted. All flights receive ATC clearance and separation is provided between IFR and VFR traffic, while VFR flights are separated from each other only on request.

Airspace of defined dimensions within which air traffic control service is provided to IFR flights and to VFR flights in accordance with the airspace classification. Dimensions and classification are published in the national AIP.

A specified route established for channelling the flow of traffic for which air traffic services are provided. It may be an airway, advisory route, or controlled route, and is published with designators and altitudes in the AIP.

An authorisation by air traffic control for an aircraft to proceed under specified traffic conditions. It does not relieve the pilot in command of responsibility for terrain clearance or safe operation of the aircraft.

The pilot's repetition of safety-related ATC instructions, such as clearances, runway assignments, and altimeter settings, to confirm correct receipt. A complete read-back is required before acting on such instructions.

A four-digit octal code entered in the aircraft transponder, assigned by ATC to identify the flight on radar displays. Pilots must set, confirm, and read back codes, and use the standard conspicuity codes when appropriate.

A radar system that interrogates aircraft transponders and displays the returned identification and altitude data to controllers. It provides range, bearing, and pressure altitude information, unlike primary radar which relies on skin reflection.

The transponder reply mode that transmits pressure altitude referenced to 1013.25 hPa. Controllers use it to verify assigned levels and to provide separation between aircraft in controlled airspace.

A message transmitted by a pilot stating the aircraft's position, time, altitude, and next estimated position, used where procedural separation is applied. It keeps controllers informed where radar coverage is absent or unreliable.

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

The angle of attack at which the wing reaches maximum lift coefficient and any further increase causes a stall. It is essentially constant regardless of weight, bank angle, or airspeed.

A condition in which the airflow separates from the wing because the critical angle of attack is exceeded, causing a loss of lift. Recovery requires reducing the angle of attack, typically by lowering the nose.

The point at which the aircraft's total weight is considered to act. Its position must remain within the certified forward and aft limits for controllability and performance, and it shifts as fuel is burned or load is moved.

The horizontal distance from the reference datum to the point where a weight acts. Multiplying a weight by its moment arm gives its moment, which is summed to locate the centre of gravity.

The calculation and control of aircraft weight and centre of gravity position to ensure they stay within certified limits. It affects take-off and landing performance, stability, and structural loading.

The greatest mass at which an aircraft is certified for the start of take-off. It is a structural and performance limit and must account for fuel, payload, and runway conditions.

The runway length needed to accelerate from rest to lift-off and reach a specified height, allowing for engine failure where applicable. It varies with mass, altitude, temperature, wind, and runway slope and surface.

The runway length needed from crossing the threshold at a specified height to a full stop. It increases with mass, tailwind, downslope, high temperature, and contamination such as water or ice.

The pressure altitude corrected for non-standard temperature, representing the altitude at which the aircraft's performance would occur in a standard atmosphere. High density altitude reduces engine power, propeller thrust, and lift.

The altitude indicated when the altimeter subscale is set to 1013.25 hPa. It is used for flight levels, performance charts, and density altitude calculations rather than for terrain clearance.

The altitude at or below which the aircraft's altitude is expressed on the local QNH and above which it is expressed as flight levels on standard pressure. It is published for each aerodrome or area.

The altimeter subscale setting that causes the instrument to indicate elevation above mean sea level when on the ground at the aerodrome. It is used below the transition altitude for terrain clearance.

A shortage of oxygen reaching body tissues, causing impaired judgement, euphoria, and loss of consciousness. It develops insidiously at altitude and is countered by supplemental oxygen and descent.

The period after loss of oxygen supply during which a person can still perform useful tasks before incapacitation. It shortens rapidly as altitude increases and is reduced by smoking, cold, and exertion.

Abnormally rapid or deep breathing that lowers blood carbon dioxide, producing dizziness, tingling, and muscle spasms. Symptoms resemble hypoxia, and treatment is controlled breathing or, if uncertain, oxygen.

A false perception of the aircraft's attitude or motion caused by misleading vestibular and visual cues, especially without external visual reference. Recovery relies on trusting flight instruments rather than sensations.

A false attitude sensation arising from the inner ear's semicircular canals and otolith organs during acceleration, deceleration, or prolonged turns. Common examples are the leans, somatogravic, and coriolis illusions.

A false sensation of pitch caused by linear acceleration or deceleration acting on the otolith organs. Strong acceleration on take-off can feel like a nose-up attitude, prompting a dangerous nose-down correction.

A reference atmosphere with sea-level pressure 1013.25 hPa, temperature 15 degrees Celsius, and a lapse rate of 1.98 degrees Celsius per 1000 feet up to 36,090 feet. It underpins altimetry and performance calculations.

The rate at which temperature decreases with height in the atmosphere. The standard average is about 2 degrees Celsius per 1000 feet, while the saturated adiabatic rate is smaller because of latent heat release.

A layer in which temperature increases with height instead of decreasing. It stabilises the air, traps haze and smoke beneath it, and can produce wind shear and reduced visibility near the surface.

A rapid change in wind speed or direction over a short distance, horizontally or vertically. It can cause sudden airspeed changes on approach or departure and is hazardous at low altitude.

A small, intense downdraught producing a diverging outflow at the surface, typically from a thunderstorm. It creates severe headwind-to-tailwind shear and is a major hazard during approach and departure.

A cumulonimbus cloud producing lightning, heavy rain, hail, gusty winds, and strong vertical currents. It passes through cumulus, mature, and dissipating stages and should be avoided by a wide margin.

The angle between true north and magnetic north at a given location, expressed as east or west. It is shown on charts and must be applied when converting between true and magnetic directions.

The angular error of a magnetic compass caused by the aircraft's own magnetic fields and electrical equipment. It varies with heading and is recorded on a calibration card in the cockpit.

The direction in which the aircraft's longitudinal axis points, measured clockwise from true north. It is derived from the true track by applying the wind correction angle.

The heading indicated by the magnetic compass after deviation is applied to the magnetic heading. It is the value the pilot flies to maintain the desired track in the air.