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CAAP ATPL Knowledge Exam study materials
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CAAP ATPL Knowledge Exam practice questions

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Question 1Air Law and ATC Procedures

Under the Chicago Convention, an aircraft registered in one contracting State may be flown over the territory of another contracting State as part of a scheduled international air service only if the service is authorised by:

  1. The State whose territory is overflown, through special permission or other authorisation Correct answer.
  2. The State of the operator's air operator certificate
  3. The State of Registry's civil aviation authority
  4. The ICAO Council's regional office

Explanation

Article 6 requires a scheduled international air service to have special permission or other authorisation from the State whose territory it operates over. It does not require a separate permit for every flight. Article 5 allows qualifying non-scheduled civil overflights without prior permission.

Question 2Air Law and ATC Procedures

An aircraft is in the cruise at FL350 when the pilot becomes aware of a passenger with a suspected heart attack. The pilot should declare:

  1. A MAYDAY because the aircraft is in immediate danger
  2. A PAN PAN because urgency exists without immediate danger to the aircraft Correct answer.
  3. A state of emergency only after ATC requests it
  4. A distress call only if the passenger's condition is confirmed fatal

Explanation

The urgency signal PAN PAN is used when a situation concerns the safety of an aircraft or person on board but does not require immediate assistance. A serious medical emergency on board normally justifies PAN PAN, which alerts ATC and allows priority handling. MAYDAY is reserved for grave and imminent danger requiring immediate assistance.

Question 3Air Law and ATC Procedures

In radio telephony, the spoken form of the abbreviation 'QNH' is:

  1. Quebec November How
  2. Queen November Hotel
  3. Quebec November Hotel Correct answer.
  4. Query November Hotel

Explanation

ICAO spelling alphabet words are used for individual letters in radio telephony, so QNH is spoken as Quebec November Hotel. QNH is the altimeter subscale setting that makes the altimeter indicate elevation above mean sea level. Using standard words avoids confusion between similar-sounding letters.

Question 4Air Law and ATC Procedures

Which document must be carried on board an internationally operating aircraft to prove that the aircraft has been maintained in accordance with the applicable airworthiness requirements?

  1. The certificate of airworthiness Correct answer.
  2. The aircraft radio station licence
  3. The journey log book
  4. The certificate of registration

Explanation

The certificate of airworthiness is issued by the State of Registry after confirming that the aircraft meets the applicable airworthiness and maintenance requirements. Under Annex 8 and Article 31 of the Chicago Convention, it must be carried on board. It is the primary document evidencing continuing airworthiness.

Question 5Air Law and ATC Procedures

An aircraft on an IFR flight in controlled airspace loses two-way radio communication. In the absence of any specified procedure, the pilot should:

  1. Continue to the destination and hold over the navigation aid until the expected approach time Correct answer.
  2. Squawk 7600 and return to the departure aerodrome
  3. Circle the last position and wait for ATC to re-establish contact
  4. Descend immediately to the lowest safe altitude and proceed visually

Explanation

The standard IFR communication failure procedure is to maintain the last assigned speed and level for a specified period, then continue along the flight plan route to the destination. At the destination, the aircraft holds over the designated navigation aid and descends according to the published communication failure procedure. This gives ATC predictable behaviour to separate other traffic.

Question 6Air Law and ATC Procedures

The minimum horizontal separation applied between two IFR aircraft in the same cruising level in a radar control area using standard radar separation is:

  1. 5 NM Correct answer.
  2. 15 NM
  3. 3 NM
  4. 10 NM

Explanation

The standard minimum radar separation between identified aircraft in controlled airspace is 5 NM horizontally, unless a reduced separation is specifically approved for the airspace. This value is used in radar separation minima and is applied with surveillance systems of adequate accuracy. Reduced minima such as 3 NM require specific approval and system capability.

Question 7Air Law and ATC Procedures

The transition level is defined as:

  1. The lowest flight level available for use above the transition altitude Correct answer.
  2. The level at which the vertical separation minimum changes
  3. The altitude at which the altimeter is set to QNH during descent
  4. The highest altitude at which QNE is used

Explanation

The transition level is the lowest flight level available for use above the transition altitude. It is determined by the appropriate ATS unit and published for the aerodrome. When descending, the altimeter is changed from QNE to QNH at the transition level, not at the transition altitude.

Question 8Air Law and ATC Procedures

An aircraft is cleared to 'line up and wait' on runway 27. This clearance authorises the aircraft to:

  1. Enter the runway and take off immediately
  2. Enter the runway and hold in the take-off position without taking off Correct answer.
  3. Backtrack the runway to the holding point
  4. Cross the runway and continue taxiing

Explanation

The instruction 'line up and wait' authorises the aircraft to enter the runway and position itself for take-off, but not to begin the take-off roll. A separate take-off clearance is required before commencing the take-off run. This instruction replaced the older phrase 'line up' in ICAO phraseology.

Question 9Air Law and ATC Procedures

A pilot receives the clearance 'Descend to FL 80, report reaching'. Which statement correctly describes the pilot's obligation?

  1. The pilot must report leaving the current level
  2. The pilot must report only if unable to comply
  3. The pilot must report passing each intermediate level
  4. The pilot must report when the aircraft reaches FL 80 Correct answer.

Explanation

The instruction 'report reaching' requires the pilot to notify ATC when the assigned level of FL 80 has been reached. Reporting leaving a level is a different instruction ('report leaving'). Clearance instructions must be read back in full when they involve levels.

Question 10Air Law and ATC Procedures

An aircraft is flying VFR at night in controlled airspace. Which condition must be satisfied?

  1. The flight must be within 10 NM of the aerodrome of departure
  2. The flight must carry a functioning autopilot
  3. The flight must remain below 3 000 ft AMSL
  4. The flight must be conducted with a continuous two-way radio watch and the required clearance Correct answer.

Explanation

Night VFR in controlled airspace requires an ATC clearance and continuous listening watch on the appropriate frequency. The aircraft must also meet the applicable night VFR meteorological and equipment requirements. Autopilots and distance limits from departure are not general conditions for night VFR.

Question 11Air Law and ATC Procedures

The pilot of an aircraft in distress should set the transponder to:

  1. Code 7500
  2. Code 2000
  3. Code 7600
  4. Code 7700 Correct answer.

Explanation

Code 7700 is the general emergency code used to indicate distress or an emergency. It alerts ATC and triggers alarm responses in the surveillance system. Codes 7500 and 7600 indicate unlawful interference and radio communication failure respectively.

Question 12Air Law and ATC Procedures

Under ICAO Annex 2, the minimum vertical separation between two aircraft flying in the same direction above FL 290 in RVSM airspace is:

  1. 1 000 ft Correct answer.
  2. 500 ft
  3. 4 000 ft
  4. 2 000 ft

Explanation

RVSM airspace between FL 290 and FL 410 reduces the standard vertical separation from 2 000 ft to 1 000 ft. Aircraft must be approved for RVSM and carry serviceable height-keeping equipment. Below FL 290 and above FL 410 the standard 2 000 ft separation applies.

Question 13Air Law and ATC Procedures

An aerodrome has a published declared distance 'TORA' of 2 400 m and 'ASDA' of 2 500 m. The 'clearway' available is:

  1. 100 m
  2. 500 m
  3. 0 m Correct answer.
  4. 200 m

Explanation

The take-off run available (TORA) is the length of runway available for the ground run, while the accelerate-stop distance available (ASDA) includes the runway plus any stopway. Clearway is the area beyond TORA included in the take-off distance available (TODA), not in ASDA. Since only TORA and ASDA are given and ASDA exceeds TORA by 100 m, the extra 100 m is stopway, not clearway, so no clearway is stated.

Question 14Air Law and ATC Procedures

An aircraft is instructed to 'hold short of runway 09 at holding point A'. The pilot should:

  1. Request a new clearance to cross the runway only after entering it
  2. Stop at holding point A and wait for further clearance before entering the runway Correct answer.
  3. Continue taxiing across the runway if no traffic is visible
  4. Enter the runway and hold on the centreline

Explanation

A 'hold short' instruction requires the aircraft to stop at the specified holding point and not enter the runway until a further clearance is received. The pilot must not cross based on visual assessment alone. This protects against runway incursions.

Question 15Air Law and ATC Procedures

A controlled flight is about to enter airspace where the altimeter setting changes from QNH to standard pressure. The pilot should set the altimeter to 1013.2 hPa:

  1. At the transition level when descending
  2. At all times above 5 000 ft
  3. Only when instructed by ATC regardless of level
  4. At the transition altitude when climbing Correct answer.

Explanation

When climbing, the altimeter is changed from QNH to standard pressure 1013.2 hPa at the transition altitude. The aircraft then flies at flight levels referenced to standard pressure. When descending, the change back to QNH occurs at the transition level.

Question 16Air Law and ATC Procedures

Which of the following best describes the purpose of a 'read-back' requirement for ATC clearances?

  1. To permit the pilot to request a different clearance
  2. To confirm the aircraft's registration and type
  3. To allow ATC to record the pilot's voice for licensing purposes
  4. To confirm that the pilot has correctly understood and will comply with the clearance Correct answer.

Explanation

Read-back ensures that the pilot has received and correctly understood safety-related clearance elements such as route, level, and heading. It provides ATC with confirmation that the instruction will be complied with. Incorrect read-backs allow ATC to detect and correct misunderstandings.

Question 17Air Law and ATC Procedures

Under ICAO rules, an aircraft operating on the ground at a controlled aerodrome must obtain a clearance before:

  1. Starting engines only
  2. Taxiing only when the visibility is below 1 500 m
  3. Taxiing, crossing a runway, and taking off Correct answer.
  4. Entering the apron only

Explanation

At a controlled aerodrome, an aircraft must obtain an ATC clearance before taxiing, crossing any runway, and taking off. These movements affect the safe use of the manoeuvring area. Engine start may also require clearance at some aerodromes, but the listed movements are the core requirements.

Question 18Air Law and ATC Procedures

An aircraft on approach is given the instruction 'Go around'. The pilot should:

  1. Continue the approach and land if the runway is clear
  2. Request a new approach clearance before climbing
  3. Reduce speed and hold over the threshold
  4. Apply take-off power, climb, and follow the published missed approach procedure or ATC instructions Correct answer.

Explanation

A go-around instruction requires the pilot to abandon the approach, apply take-off power, and climb. The pilot then follows the published missed approach procedure or any ATC instructions. Continuing the approach after a go-around instruction is not permitted.

Question 19Air Law and ATC Procedures

An aircraft is flying at FL 100 in airspace where the transition altitude is 5 000 ft and the transition level is FL 70. The altimeter should be set to:

  1. The aerodrome QNH of the nearest aerodrome
  2. 1013.2 hPa Correct answer.
  3. QFE
  4. QNH

Explanation

At FL 100 the aircraft is above the transition level of FL 70, so the altimeter must be referenced to standard pressure 1013.2 hPa. Flight levels are always referenced to standard pressure. QNH is used only at or below the transition altitude.

Question 20Air Law and ATC Procedures

An aircraft is intercepted by a military aircraft. The intercepting aircraft rocks its wings and then makes a slow level turn in the desired direction. The intercepted aircraft should:

  1. Continue on its current heading and ignore the signal
  2. Follow the intercepting aircraft and acknowledge by rocking its wings Correct answer.
  3. Squawk 7600 and turn away from the intercepting aircraft
  4. Descend immediately and land at the nearest aerodrome

Explanation

ICAO interception signals require the intercepted aircraft to follow the intercepting aircraft and acknowledge by rocking its wings. The intercepting aircraft uses a sequence of signals to direct the intercepted aircraft to a suitable aerodrome. The intercepted aircraft should also attempt to establish radio communication.

Question 21Air Law and ATC Procedures

A pilot is cleared to descend from FL 300 to FL 200 at a specified time. The aircraft is not equipped with a working transponder. Which consequence applies in most controlled airspaces?

  1. The aircraft may be denied entry into airspace where a transponder is mandatory Correct answer.
  2. The pilot must reduce speed to 250 kt
  3. The aircraft may still be cleared into the airspace without restriction
  4. The pilot must squawk 2000 instead

Explanation

Many controlled airspaces require aircraft to carry and operate a serviceable transponder with Mode C or Mode S capability. An aircraft without a working transponder may be denied entry or given special conditions. Squawking 2000 does not substitute for a serviceable transponder.

Question 22Air Law and ATC Procedures

An operator plans a flight under the provisions of Annex 6 Part I. Which statement correctly describes the requirement for an operational flight plan?

  1. It must be prepared for every flight and include the information specified by the operator's authority Correct answer.
  2. It is required only for flights exceeding 3 hours
  3. It is optional if the flight is conducted under IFR
  4. It must be filed with ATC before departure

Explanation

Annex 6 requires the operator to ensure that an operational flight plan is prepared for every flight, containing the specified information such as fuel, route, and alternates. It is retained by the operator and is not the same as an ATC flight plan. The flight plan may be in electronic form.

Question 23Air Law and ATC Procedures

An aircraft is cleared to 'descend when ready, maintain FL 180'. The pilot may:

  1. Begin descent at any time after accepting the clearance, provided FL 180 is reached at the specified point Correct answer.
  2. Begin descent only after passing the next waypoint
  3. Begin descent only when instructed by a separate clearance
  4. Begin descent only if the aircraft is equipped with autopilot

Explanation

The phrase 'when ready' gives the pilot discretion to begin the descent at a suitable time, provided the assigned level is reached at the specified point. The pilot remains responsible for terrain clearance and separation from other aircraft. A separate clearance is not required.

Question 24Air Law and ATC Procedures

An aircraft is flying at FL 290 with an indicated altitude of 29 000 ft and an actual QNH of 1 005 hPa. The true altitude of the aircraft is approximately:

  1. Equal to 29 000 ft plus the pressure altitude correction
  2. Below 29 000 ft Correct answer.
  3. Above 29 000 ft
  4. Equal to 29 000 ft

Explanation

When the QNH is below standard pressure, the true altitude is lower than the indicated altitude. Standard pressure is 1 013.2 hPa, and the actual QNH of 1 005 hPa is lower, so the aircraft is lower than indicated. This is why pilots must apply temperature and pressure corrections when flying at low temperatures.

Question 25Aircraft General Knowledge - Airframe, Systems and Powerplant

In a transport-category aeroplane, the primary structural function of the wing spar caps is to carry which loads?

  1. Shear, transferring vertical loads from skin to ribs
  2. Bending moments, converting them into axial tension and compression in the caps Correct answer.
  3. Torsion, reacting the twisting moment between front and rear spars
  4. Chordwise compression from aerodynamic suction on the upper skin

Explanation

Spar caps are positioned at the maximum distance from the neutral axis, so bending moments are resisted most efficiently as axial tension in one cap and compression in the other. Shear webs carry shear and torsion, while the skin carries much of the torsional and chordwise load.

Question 26Aircraft General Knowledge - Airframe, Systems and Powerplant

A semi-monocoque fuselage derives most of its strength from which combination?

  1. Rigid internal truss with non-load-bearing skin
  2. A single central keel beam carrying all bending
  3. Pressure bulkheads alone, with skin acting only as fairing
  4. Stressed skin working with stringers, frames and bulkheads Correct answer.

Explanation

In semi-monocoque construction the skin is stressed and works together with longitudinal stringers and circumferential frames to carry shear, bending and pressure loads. The skin is not merely a fairing, and no single member carries all bending.

Question 27Aircraft General Knowledge - Airframe, Systems and Powerplant

During a normal pressurisation cycle, what is the function of the negative pressure relief valve?

  1. It regulates the rate of cabin climb to a selected value
  2. It limits the maximum positive differential pressure at altitude
  3. It dumps cabin pressure during an emergency descent
  4. It opens to prevent cabin pressure from falling excessively below ambient Correct answer.

Explanation

The negative pressure relief valve protects the structure if cabin pressure drops below external ambient, for example during a rapid descent, by allowing air to flow inward. Positive differential limitation is the job of the positive pressure relief valve, and rate control belongs to the outflow valve.

Question 28Aircraft General Knowledge - Airframe, Systems and Powerplant

In a boot-type pneumatic de-icing system, ice is removed primarily by which mechanism?

  1. A weeping glycol film prevents ice from bonding to the surface
  2. Continuous heating keeps the surface above freezing point
  3. Inflation of the boots cracks and sheds the ice accreted on them Correct answer.
  4. Electrically heated mats melt a thin water layer under the ice

Explanation

Pneumatic boots inflate cyclically, expanding the surface so the ice layer cracks and is shed into the airstream. They operate after ice has formed, unlike anti-icing systems that prevent formation.

Question 29Aircraft General Knowledge - Airframe, Systems and Powerplant

Which hydraulic system component converts pressure energy into controlled flow to move an actuator at a rate proportional to a command?

  1. Accumulator
  2. Pressure relief valve
  3. Servo valve Correct answer.
  4. Check valve

Explanation

A servo valve meters flow to an actuator in proportion to an electrical or mechanical command, controlling both direction and rate of movement. Relief valves protect against overpressure, accumulators store energy, and check valves enforce one-way flow.

Question 30Aircraft General Knowledge - Airframe, Systems and Powerplant

A hydraulic accumulator pre-charged with nitrogen to 1000 psi is used in a 3000 psi system. What is its main operational benefit?

  1. It cools the hydraulic fluid during sustained operation
  2. It increases the maximum system pressure to 3000 psi
  3. It removes air from the hydraulic fluid
  4. It supplies flow for peak demands and damps pressure surges Correct answer.

Explanation

The gas charge allows the accumulator to store fluid under pressure, supplying additional flow during transient high demand and absorbing pressure pulses. It does not raise the regulated system pressure, which is set by the pump and relief valve.

Question 31Aircraft General Knowledge - Airframe, Systems and Powerplant

In a DC generation system, what is the purpose of the overvoltage protection relay?

  1. It reverses the field to reduce output voltage
  2. It trips the generator offline when voltage exceeds a set limit Correct answer.
  3. It limits current to prevent cable overheating
  4. It disconnects the battery from the bus during charging

Explanation

Overvoltage protection removes a generator from the bus when its voltage rises above a safe threshold, protecting equipment from excessive voltage. Current limitation and reverse-current protection are separate functions.

Question 32Aircraft General Knowledge - Airframe, Systems and Powerplant

Why is a constant-speed drive used with an engine-driven AC generator?

  1. To convert AC output to DC for the battery bus
  2. To provide a second source of AC during engine start
  3. To keep generator frequency constant as engine speed varies Correct answer.
  4. To increase generator voltage at low engine speed

Explanation

AC generator frequency is proportional to rotational speed, so a constant-speed drive regulates input speed to hold frequency at 400 Hz. Voltage regulation is a separate function of the generator control unit.

Question 33Aircraft General Knowledge - Airframe, Systems and Powerplant

What is the primary function of a fuel boost pump in the wing tank of a jet transport?

  1. To measure fuel quantity by pumping a known volume
  2. To transfer fuel between tanks for CG control
  3. To supply fuel at positive pressure to the engine feed line and prevent cavitation Correct answer.
  4. To vent the tank to atmosphere during refuelling

Explanation

Boost pumps pressurise the fuel at the engine feed point so the engine-driven pump receives liquid fuel rather than vapour, preventing cavitation at altitude. Fuel transfer and quantity measurement are separate subsystems.

Question 34Aircraft General Knowledge - Airframe, Systems and Powerplant

In a jet engine fuel system, what is the function of the fuel-oil heat exchanger?

  1. It cools the fuel before it enters the combustion chamber
  2. It mixes oil into the fuel to improve combustion
  3. It warms the fuel using engine oil while cooling the oil Correct answer.
  4. It separates water from the fuel by centrifugal action

Explanation

The fuel-oil heat exchanger transfers heat from hot engine oil to the colder fuel, cooling the oil and warming the fuel to prevent ice crystals blocking the fuel filter. It does not mix the two fluids.

Question 35Aircraft General Knowledge - Airframe, Systems and Powerplant

Which statement correctly describes the operation of a free-turbine turboprop engine?

  1. The propeller speed is fixed to compressor speed by a single shaft
  2. The propeller is driven by exhaust thrust alone without a turbine
  3. The propeller is driven by a turbine stage mechanically independent of the gas generator Correct answer.
  4. The propeller is driven directly from the compressor shaft through a fixed gearbox

Explanation

In a free-turbine design the power turbine is aerodynamically coupled to but mechanically separate from the gas generator, allowing the propeller to run at its own speed. This independence is what allows the propeller to be optimised separately from the compressor.

Question 36Aircraft General Knowledge - Airframe, Systems and Powerplant

During a jet engine start, what does a hung start typically indicate?

  1. The exhaust gas temperature stays far below normal limits
  2. The engine accelerates too slowly and stabilises below idle, usually from insufficient starting air or fuel scheduling Correct answer.
  3. The engine accelerates too rapidly, exceeding idle speed
  4. The starter cuts out before light-off occurs

Explanation

A hung start occurs when the engine lights off but fails to accelerate to idle, often because of low starter air pressure, weak ignition, or incorrect fuel scheduling. It is characterised by stagnation at a low RPM with rising EGT.

Question 37Aircraft General Knowledge - Airframe, Systems and Powerplant

What is the purpose of variable inlet guide vanes on an axial compressor?

  1. To cool the compressor casing during high-power operation
  2. To bleed air from the compressor for cabin pressurisation
  3. To adjust airflow angle to the first stage and improve stall margin at low speeds Correct answer.
  4. To increase the pressure ratio at maximum RPM only

Explanation

Variable inlet guide vanes change the angle of airflow entering the first compressor stage, matching the flow to blade incidence at low corrected speeds and thereby improving stall margin. Bleed air for the cabin is taken from separate ports.

Question 38Aircraft General Knowledge - Airframe, Systems and Powerplant

A twin-spool axial compressor uses separate HP and LP rotors. What is the main advantage of this arrangement?

  1. It eliminates the need for a combustion chamber
  2. Each spool can run at its own optimum speed, improving stall margin and efficiency Correct answer.
  3. It removes the need for turbine cooling
  4. It allows the engine to run without a fuel control unit

Explanation

Separate spools let the LP and HP compressors rotate at speeds suited to their own blade geometry, which widens the stable operating range and improves efficiency. Combustion and fuel control remain essential regardless of spool count.

Question 39Aircraft General Knowledge - Airframe, Systems and Powerplant

Which parameter is used to compare engine operating conditions corrected to standard sea-level conditions?

  1. Corrected speed, obtained by adjusting RPM for inlet temperature Correct answer.
  2. Exhaust gas temperature alone
  3. Oil pressure in psi
  4. Fuel flow in kilograms per hour

Explanation

Corrected speed (N/√θ) accounts for inlet temperature so that engine parameters can be compared with the manufacturer's charts regardless of ambient conditions. EGT, fuel flow and oil pressure are not corrected in this way.

Question 40Aircraft General Knowledge - Airframe, Systems and Powerplant

What is the primary purpose of compressor bleed valves during engine acceleration?

  1. To release excess air and prevent compressor stall at low corrected speed Correct answer.
  2. To increase the pressure ratio during acceleration
  3. To supply air to the combustion chamber for ignition
  4. To cool the turbine blades during start

Explanation

Bleed valves open at low corrected speeds to reduce back-pressure in the compressor, keeping blade incidence within stall-free limits during acceleration. They close as speed increases and the compressor can handle the full flow.

Question 41Aircraft General Knowledge - Airframe, Systems and Powerplant

In a turbofan engine, what does the bypass ratio describe?

  1. The ratio of thrust to engine weight
  2. The ratio of fan pressure to compressor pressure
  3. The ratio of mass flow through the bypass duct to mass flow through the core Correct answer.
  4. The ratio of turbine inlet temperature to compressor outlet temperature

Explanation

Bypass ratio is the mass flow of air passing through the fan duct divided by the mass flow entering the core. High bypass ratios improve propulsive efficiency and reduce noise.

Question 42Aircraft General Knowledge - Airframe, Systems and Powerplant

What happens to the thrust of a fixed-pitch propeller as airspeed increases at constant RPM?

  1. Thrust decreases because the angle of attack of the blades relative to the airflow reduces Correct answer.
  2. Thrust increases until the blade stalls at high speed
  3. Thrust remains constant because RPM is constant
  4. Thrust increases because ram air improves blade efficiency

Explanation

For a fixed-pitch propeller at constant RPM, the helix angle stays the same while the airflow angle changes with forward speed, reducing blade angle of attack and therefore thrust. Thrust falls to zero at the speed where blade angle of attack becomes zero.

Question 43Aircraft General Knowledge - Airframe, Systems and Powerplant

What is the purpose of propeller feathering on a multi-engine aeroplane?

  1. To rotate the blades to minimum drag alignment after an engine failure Correct answer.
  2. To lock the propeller at fine pitch for windmilling
  3. To reverse thrust after landing
  4. To increase blade pitch for maximum take-off thrust

Explanation

Feathering turns the blades edge-on to the relative airflow so that a failed engine's propeller produces minimum drag and does not windmill. Reverse thrust and fine pitch are separate pitch settings used for other purposes.

Question 44Aircraft General Knowledge - Airframe, Systems and Powerplant

An aircraft experiences a sudden loss of cabin pressure at high altitude. What is the correct crew action regarding the pressurisation system?

  1. Turn off the air-conditioning packs to reduce noise
  2. Increase cabin pressure to counter the loss
  3. Close the bleed valves to preserve engine power
  4. Don oxygen masks, initiate emergency descent, and select the outflow valve to control cabin altitude Correct answer.

Explanation

The immediate priorities are oxygen for the crew and passengers and a rapid descent to a breathable altitude, with the outflow valve managed to control cabin pressure. Increasing pressure is impossible with a breached cabin, and closing bleed valves does not restore pressure.

Question 45Aircraft General Knowledge - Airframe, Systems and Powerplant

What is the function of the anti-shimmy damper on a nose landing gear?

  1. To absorb vertical landing loads
  2. To damp oscillations of the nose wheel about its steering axis Correct answer.
  3. To retract the gear after take-off
  4. To lock the gear in the down position

Explanation

The shimmy damper resists rapid oscillation of the nose wheel about its vertical axis, preventing shimmy during take-off and landing. Vertical load absorption is the job of the oleo strut, and locking is handled by down-locks.

Question 46Aircraft General Knowledge - Airframe, Systems and Powerplant

In a carbon-fibre composite wing skin, how is damage such as delamination typically detected?

  1. By magnetic particle inspection
  2. By dye penetrant inspection
  3. By eddy current inspection
  4. By ultrasonic or tap-test inspection methods that reveal internal separation Correct answer.

Explanation

Delamination in composite laminates is an internal separation between plies, so ultrasonic scanning and tap testing are used to detect it. Magnetic particle, dye penetrant and eddy current methods are suited to metallic structures.

Question 47Aircraft General Knowledge - Airframe, Systems and Powerplant

What is the purpose of a torque link on an oleo-pneumatic landing gear strut?

  1. To lock the gear in the retracted position
  2. To damp vertical oscillations during taxi
  3. To transmit torsional loads between the upper and lower strut while allowing vertical travel Correct answer.
  4. To provide the main vertical spring force

Explanation

Torque links connect the upper and lower strut halves and react torque about the strut axis, keeping the wheel aligned while the strut slides vertically. Spring and damping forces come from the gas charge and metering orifice inside the strut.

Question 48Aircraft General Knowledge - Airframe, Systems and Powerplant

Why is a wet-sump lubrication system generally unsuitable for high-performance jet engines?

  1. It operates only at low altitudes by design
  2. It cannot circulate oil to the bearings
  3. The oil supply is stored in the engine sump, which limits oil capacity and risks foaming at altitude Correct answer.
  4. It requires no oil cooler

Explanation

In a wet-sump system the oil is carried in the engine itself, which restricts capacity and exposes the oil to foaming and coking at high altitude and temperature. Jet engines typically use a dry-sump system with a separate tank.

Question 49Aircraft General Knowledge - Instrumentation

In a conventional pitot-static system, which pressure source is connected to the input of the airspeed indicator?

  1. Pitot pressure only
  2. Both pitot and static pressure Correct answer.
  3. Static pressure only
  4. Total pressure minus cabin pressure

Explanation

The airspeed indicator is a differential pressure instrument that receives pitot (total) pressure in one capsule and static pressure on the surrounding case. The difference between total and static pressure is dynamic pressure, which is converted to an indicated airspeed. Neither source alone can produce an airspeed reading.

Question 50Aircraft General Knowledge - Instrumentation

An aircraft climbs at a constant true airspeed while the outside air temperature falls. What happens to the indicated airspeed?

  1. It remains constant
  2. It fluctuates with the static source error
  3. It decreases Correct answer.
  4. It increases

Explanation

Indicated airspeed depends on dynamic pressure, which for a given true airspeed falls as air density decreases with altitude. In a climb with decreasing density the dynamic pressure and therefore the indicated airspeed reduce, even though true airspeed is unchanged. This is why true airspeed is always higher than indicated airspeed at altitude.