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GCAA CPL Theory Exam study materials
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GCAA CPL Theory Exam (GCAA) practice questions

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Question 1Air Law and ATC Procedures

Under the ICAO Convention on International Civil Aviation (Chicago Convention), which document must every aircraft engaged in international navigation carry to prove its nationality and registration?

  1. The certificate of airworthiness
  2. The journey logbook
  3. The certificate of registration Correct answer.
  4. The crew licences

Explanation

Article 29 of the Chicago Convention lists the documents an aircraft engaged in international navigation must carry, and the certificate of registration is what evidences the aircraft's nationality and registration. The certificate of airworthiness, crew licences and journey logbook are also on that list but serve different purposes.

Question 2Air Law and ATC Procedures

An aircraft is being operated in a Contracting State's territory. Which statement correctly describes the nationality rule for aircraft under the Chicago Convention?

  1. Aircraft have the nationality of the operator's State of incorporation
  2. Aircraft have the nationality of the State in which they are registered Correct answer.
  3. Aircraft have the nationality of the State issuing the crew licences
  4. Aircraft have no nationality and are governed only by the overflown State

Explanation

Article 17 of the Chicago Convention provides that aircraft have the nationality of the State in which they are registered. Registration may be made only in one State, and the aircraft cannot validly be registered in more than one State. The operator's home State, the overflown State and the licensing State do not confer nationality.

Question 3Air Law and ATC Procedures

What is the standard unit of vertical distance used in air traffic control clearances and in the altimeter setting procedures described in ICAO Annex 5?

  1. The nautical mile
  2. The foot Correct answer.
  3. The metre
  4. The statute mile

Explanation

ICAO uses the foot as the primary unit of vertical distance for altimetry and level clearances, while the metre is used for many horizontal dimensions. The nautical mile is the unit of horizontal distance used in navigation. Annex 5 sets out these units and their permitted use.

Question 4Air Law and ATC Procedures

In the ICAO phonetic alphabet, which word represents the letter Q?

  1. Queen
  2. Quartz
  3. Quito
  4. Quebec Correct answer.

Explanation

The ICAO spelling alphabet assigns Quebec to the letter Q. The alphabet is standardised so that letters can be transmitted unambiguously over radiotelephony. Quito, Queen and Quartz are not part of the standard alphabet.

Question 5Air Law and ATC Procedures

When transmitting a heading of 270 degrees in radiotelephony, how should the digits be spoken?

  1. Two hundred seventy
  2. Two seven zero heading
  3. Two seven zero Correct answer.
  4. Two seven zero degrees

Explanation

In ICAO radiotelephony, headings are transmitted as three separate digits, and the word 'degrees' is normally omitted. So 270 is spoken as 'two seven zero'. Each digit is pronounced individually to avoid confusion.

Question 6Air Law and ATC Procedures

An aircraft on approach receives the instruction 'cleared to land'. What does this clearance authorise the pilot to do?

  1. Descend below the minima without visual reference
  2. Proceed to land on the specified runway Correct answer.
  3. Enter the traffic circuit without further clearance
  4. Taxi to the apron after touchdown

Explanation

A landing clearance authorises the aircraft to proceed and land on the runway specified in the clearance. It does not relieve the pilot of the responsibility to ensure the runway is clear and that landing can be made safely. Taxiing after landing requires a separate taxi clearance.

Question 7Air Law and ATC Procedures

Which body is responsible for establishing and maintaining the standards and recommended practices annexed to the Chicago Convention?

  1. The ICAO Council, acting with the Air Navigation Commission Correct answer.
  2. The United Nations Security Council
  3. The International Air Transport Association
  4. The operator's national civil aviation authority alone

Explanation

The ICAO Council adopts Standards and Recommended Practices, which are developed with the assistance of the Air Navigation Commission and then annexed to the Convention. National authorities implement them, and IATA is an industry association without that power.

Question 8Air Law and ATC Procedures

An aircraft is cleared to descend to flight level 100. Which altimeter setting is used when flying at a flight level?

  1. The standard pressure setting of 1013.2 hPa Correct answer.
  2. The QNH of the destination aerodrome
  3. The QFE of the departure aerodrome
  4. The local QNH of the nearest aerodrome

Explanation

Flight levels are referenced to the standard pressure setting of 1013.2 hPa, which ensures all aircraft at flight levels use the same datum. QNH and QFE are used for altitudes and heights near the ground, not for flight levels.

Question 9Air Law and ATC Procedures

You are flying in controlled airspace at flight level 120 and the transition level is flight level 110. Which statement is correct?

  1. You must set the local QNH and fly at an altitude
  2. You may choose either setting at your discretion
  3. You must set QFE until established on approach
  4. You must set the standard pressure setting and remain at a flight level Correct answer.

Explanation

Above the transition level, aircraft are flown at flight levels with the standard pressure setting 1013.2 hPa. Below the transition level, QNH is used to give altitude. Because FL120 is above the transition level of FL110, the standard setting applies.

Question 10Air Law and ATC Procedures

An aircraft is instructed to 'hold short of runway 27 at the holding point'. What does this instruction require?

  1. Taxi onto the runway and wait there
  2. Cross runway 27 immediately without stopping
  3. Stop at the holding point and not enter the runway until cleared Correct answer.
  4. Enter the runway and hold position at the threshold

Explanation

A 'hold short' instruction requires the aircraft to stop at the designated holding point and remain clear of the runway until an explicit clearance to enter or cross is received. It does not authorise crossing or entering the runway.

Question 11Air Law and ATC Procedures

What is the meaning of the instruction 'line up and wait' given to an aircraft at a runway holding point?

  1. Enter the runway and stop, awaiting take-off clearance Correct answer.
  2. Cross the runway and continue taxiing
  3. Begin the take-off roll immediately
  4. Hold at the holding point until further advised

Explanation

'Line up and wait' authorises the aircraft to enter the runway and position itself for take-off, but it must then stop and await take-off clearance. It is not a take-off clearance and does not authorise crossing the runway.

Question 12Air Law and ATC Procedures

Which condition must be met before a pilot may descend below the decision altitude during an instrument approach?

  1. The required visual reference to continue the approach has been established Correct answer.
  2. The aircraft's landing gear is extended
  3. The tower has reported the runway clear
  4. The aircraft has passed the final approach fix

Explanation

Descent below the decision altitude is permitted only when the required visual reference for the intended runway is distinctly visible and the pilot can continue the approach to land. Passing the final approach fix or having the gear extended does not by itself authorise descent below minima.

Question 13Air Law and ATC Procedures

An ATC clearance is issued to an aircraft, but the pilot cannot comply for safety reasons. What is the correct action?

  1. Inform ATC immediately and request an amended clearance Correct answer.
  2. Comply with the clearance regardless of the safety concern
  3. Ignore the clearance and continue on the previous route
  4. Land at the nearest aerodrome without notifying ATC

Explanation

A pilot who cannot accept or comply with a clearance must advise ATC promptly and request an amended clearance. The pilot in command remains responsible for the safety of the flight and may not simply ignore the clearance.

Question 14Air Law and ATC Procedures

Which of the following correctly describes a 'readback' requirement for a clearance to enter a runway?

  1. The pilot must acknowledge with the word 'roger' only
  2. The pilot must acknowledge only if requested by ATC
  3. The pilot must acknowledge after take-off
  4. The pilot must repeat the clearance to allow ATC to verify it Correct answer.

Explanation

Clearances to enter, cross or take off from a runway must be read back in full so that ATC can verify that the instruction has been correctly received. A simple 'roger' does not satisfy the readback requirement.

Question 15Air Law and ATC Procedures

In the event of a radio communication failure in IMC, which action is consistent with the standard ICAO procedure?

  1. Switch off the transponder and proceed to the destination
  2. Turn back to the departure aerodrome without clearance
  3. Descend immediately to the lowest safe altitude and circle
  4. Continue according to the last acknowledged clearance and the applicable lost-communication procedure Correct answer.

Explanation

The standard lost-communication procedure requires the aircraft to continue in accordance with the last acknowledged clearance and the published procedure, maintaining the assigned route and levels. The transponder should be set to the appropriate code to alert ATC.

Question 16Air Law and ATC Procedures

Which of the following is a 'Standard' in an ICAO Annex?

  1. A specification whose uniform application is recognised as necessary for safety Correct answer.
  2. A national regulation adopted without reference to ICAO
  3. A specification whose uniform application is desirable but not essential
  4. A recommendation issued by an airline

Explanation

A Standard is any specification whose uniform application is recognised as necessary for the safety or regularity of international air navigation. A Recommended Practice is one whose uniform application is desirable but not essential. Both are distinguished from national regulations and airline procedures.

Question 17Air Law and ATC Procedures

An aircraft is on a heading of 090 and ATC issues the instruction 'turn left heading 180'. Which turn should the pilot make?

  1. A left turn through 90 degrees to heading 180 Correct answer.
  2. A right turn through 90 degrees to heading 180
  3. A left turn through 270 degrees to heading 180
  4. A right turn through 270 degrees to heading 180

Explanation

The instruction specifies the direction of turn, so the pilot makes a left turn from 090 to 180, which is a 90-degree turn. Specifying the direction avoids ambiguity about which way to turn.

Question 18Air Law and ATC Procedures

Which transponder code is used to indicate a general emergency?

  1. 7500
  2. 7600
  3. 7000
  4. 7700 Correct answer.

Explanation

Code 7700 is the general emergency code. Code 7600 indicates radio communication failure and code 7500 indicates unlawful interference. Code 7000 is a conspicuity code used in some regions for VFR flight.

Question 19Air Law and ATC Procedures

An aircraft is cleared for take-off on runway 09. During the take-off roll the pilot observes a vehicle entering the runway ahead. What is the correct action?

  1. Continue the take-off and attempt to climb over the vehicle
  2. Swerve around the vehicle and continue the take-off
  3. Continue and advise ATC after becoming airborne
  4. Abandon the take-off if stopping can be achieved safely, and advise ATC Correct answer.

Explanation

If an obstacle enters the runway during the take-off roll, the pilot should reject the take-off provided it can be stopped safely within the remaining runway. Continuing and attempting to avoid the vehicle by climbing or swerving is not a safe option. ATC must be advised of the rejected take-off.

Question 20Air Law and ATC Procedures

An aircraft is cleared to fly at flight level 110 in a region where the transition level is flight level 100. The pilot's altimeter is set to QNH. What is the consequence?

  1. The aircraft's level will not be referenced to the standard datum, compromising separation Correct answer.
  2. The aircraft must immediately change to QFE
  3. The clearance becomes invalid and the pilot must land
  4. The aircraft's altitude will be correct because QNH equals the standard setting

Explanation

Flight levels are referenced to the standard pressure setting of 1013.2 hPa, so flying at a flight level with QNH set means the aircraft is not at the cleared level relative to other aircraft. This compromises the vertical separation on which the clearance depends.

Question 21Air Law and ATC Procedures

A pilot receives a clearance containing a route that conflicts with the aircraft's performance limitations. Which action best reflects the pilot's responsibility under air law?

  1. Accept the clearance and attempt the route regardless
  2. Accept the clearance and deviate without advising ATC
  3. Request an amended clearance before accepting the route Correct answer.
  4. Decline to respond and continue on the previous route

Explanation

The pilot in command is responsible for the safety of the flight and must not accept a clearance that cannot be complied with. The correct action is to request an amended clearance before accepting the route. Deviating without advising ATC or ignoring the clearance is not acceptable.

Question 22Air Law and ATC Procedures

An aircraft is instructed to 'report passing 5000 feet'. What does this instruction require?

  1. Set the altimeter to 5000 feet
  2. Advise ATC when the aircraft passes through 5000 feet Correct answer.
  3. Report the altitude at the next waypoint
  4. Maintain 5000 feet until further advised

Explanation

A report passing instruction requires the pilot to advise ATC at the moment the aircraft passes through the specified altitude. It does not change the assigned level or the altimeter setting.

Question 23Air Law and ATC Procedures

An aircraft is cleared to descend to 3000 feet with QNH 1003 hPa. The pilot's altimeter is set to 1013 hPa. How will the actual altitude compare with the cleared altitude?

  1. The aircraft will be at 3000 feet only if QFE is set
  2. The aircraft will be lower than 3000 feet Correct answer.
  3. The aircraft will be exactly at 3000 feet
  4. The aircraft will be higher than 3000 feet

Explanation

With QNH lower than the standard setting, the true altitude is lower than the indicated altitude when the altimeter is set to the standard setting. Setting 1013 hPa instead of the correct QNH of 1003 hPa therefore places the aircraft below the cleared altitude.

Question 24Air Law and ATC Procedures

An aircraft is instructed to 'squawk ident'. What is the pilot's correct response?

  1. Set the transponder to code 7600
  2. Press the ident button on the transponder Correct answer.
  3. Change the transponder code to 7000
  4. Switch the transponder to standby

Explanation

'Squawk ident' instructs the pilot to activate the identification feature of the transponder so that the controller can identify the aircraft's radar return. It does not change the assigned code.

Question 25Aircraft General Knowledge - Airframe, Systems and Powerplant

In a semi-monocoque aircraft fuselage, what is the primary function of the stringers?

  1. They provide the aerodynamic shape by forming the outer contour only
  2. They carry the bending loads and stiffen the skin against buckling Correct answer.
  3. They act as the main attachment points for the landing gear only
  4. They hold the engine mounts and absorb all vibration loads

Explanation

In semi-monocoque construction the skin carries part of the load, while longitudinal stringers and frames stiffen it and help carry bending and shear. The stringers therefore resist bending and prevent the skin from buckling under compression. They are not the sole load path nor the primary source of aerodynamic contour.

Question 26Aircraft General Knowledge - Airframe, Systems and Powerplant

A wing spar that is designed to resist bending loads is normally arranged to run in which direction in a conventional wing?

  1. Spanwise from root to tip Correct answer.
  2. Diagonally at 45 degrees to the chord
  3. Chordwise from leading to trailing edge
  4. Vertically through the wing thickness

Explanation

The spar is the main spanwise beam of the wing and carries bending moments produced by lift toward the wing root. Its spanwise orientation places the material where it can resist bending most efficiently. Chordwise members such as ribs redistribute loads and maintain aerofoil shape.

Question 27Aircraft General Knowledge - Airframe, Systems and Powerplant

What is the main purpose of the ribs inside a wing structure?

  1. They maintain the aerofoil shape and transmit loads to the spar Correct answer.
  2. They carry the entire bending load from root to tip
  3. They contain the fuel and seal it from the outside air
  4. They provide the attachment for the wing-to-fuselage joint

Explanation

Ribs are chordwise members that preserve the aerofoil profile and support the skin, transferring local loads into the spars. They do not carry the primary spanwise bending load, which is the spar's role. Their shape control is essential to maintaining aerodynamic efficiency.

Question 28Aircraft General Knowledge - Airframe, Systems and Powerplant

Which type of landing gear arrangement uses a single main wheel on the centreline plus outrigger wheels near the wingtips?

  1. Bicycle gear Correct answer.
  2. Tandem gear with a tailwheel
  3. Tricycle gear
  4. Conventional tailwheel gear

Explanation

Bicycle landing gear has main wheels on the fuselage centreline and uses small outrigger wheels to prevent tipping. This layout is used on some large aircraft where wing-mounted main gear is impractical. It is distinct from tricycle and tailwheel arrangements.

Question 29Aircraft General Knowledge - Airframe, Systems and Powerplant

During retraction of a hydraulic landing gear system, what is the function of the downlock actuator or spring?

  1. It holds the gear positively in the down and locked position Correct answer.
  2. It brakes the wheels during retraction
  3. It releases the up-lock during extension
  4. It retracts the gear faster by assisting the hydraulic pressure

Explanation

The downlock mechanism is a positive locking device that keeps the gear extended and locked even if hydraulic pressure is lost. This prevents inadvertent retraction on the ground or in flight. It does not assist retraction or apply wheel brakes.

Question 30Aircraft General Knowledge - Airframe, Systems and Powerplant

On an aircraft with a tricycle landing gear, which wheels are normally fitted with brakes?

  1. The nosewheel and the left main wheel only
  2. All three wheels equally
  3. The two main wheels Correct answer.
  4. The nosewheel only

Explanation

In tricycle gear the main wheels carry most of the aircraft weight and provide the braking force. The nosewheel is usually unbraked to allow steering and to avoid nose-over loads. Differential braking on the mains also assists ground steering.

Question 31Aircraft General Knowledge - Airframe, Systems and Powerplant

In a hydraulic system, what is the purpose of the pressure relief valve?

  1. It filters contaminants from the hydraulic fluid
  2. It limits system pressure by returning excess fluid to the reservoir Correct answer.
  3. It isolates the system from the engine-driven pump during normal operation
  4. It maintains a constant flow rate to the actuators

Explanation

The relief valve protects the system from overpressure by opening and bypassing excess fluid back to the reservoir or return line. It acts as a safety device rather than a flow controller. Normal pressure regulation is usually done by the pump's own compensator or an unloading valve.

Question 32Aircraft General Knowledge - Airframe, Systems and Powerplant

Which component in a hydraulic system stores pressurised fluid to absorb pressure surges and provide a reserve of pressure?

  1. The reservoir
  2. The accumulator Correct answer.
  3. The check valve
  4. The selector valve

Explanation

An accumulator contains a gas charge separated from the hydraulic fluid and stores energy under pressure. It smooths pressure fluctuations and can supply limited emergency pressure. The reservoir stores fluid at low pressure, not pressurised energy.

Question 33Aircraft General Knowledge - Airframe, Systems and Powerplant

What is the function of a hydraulic fuse in an aircraft hydraulic system?

  1. It regulates the pump output pressure
  2. It shuts off flow to a leaking downstream component to preserve system pressure Correct answer.
  3. It filters fine particles from the fluid
  4. It melts at high temperature to release pressure

Explanation

A hydraulic fuse detects excessive flow, such as from a ruptured line, and closes to isolate the faulty branch. This preserves the remaining system pressure for other users. It is a flow-sensitive isolation device, not a thermal or filtration component.

Question 34Aircraft General Knowledge - Airframe, Systems and Powerplant

In a pneumatic system using engine bleed air, what is the function of the pressure-reducing valve?

  1. It increases the bleed pressure before delivery
  2. It lowers the bleed pressure to the value required by the user system Correct answer.
  3. It measures the bleed air temperature
  4. It removes water from the bleed air

Explanation

Bleed air leaves the engine at high pressure and must be reduced to a usable level for systems such as air conditioning or anti-icing. The pressure-reducing valve regulates downstream pressure to the required value. Water removal and temperature sensing are separate functions.

Question 35Aircraft General Knowledge - Airframe, Systems and Powerplant

What is the primary purpose of the anti-icing system on an aircraft wing leading edge?

  1. To prevent ice formation on the protected surface Correct answer.
  2. To cool the leading edge in high-speed flight
  3. To remove ice that has already formed on the trailing edge
  4. To increase lift during take-off

Explanation

Anti-icing systems supply heat or fluid to the protected surface before ice can form, keeping it clear. De-icing systems, by contrast, remove ice after it has accumulated. The leading edge is protected because ice there most severely degrades lift and increases drag.

Question 36Aircraft General Knowledge - Airframe, Systems and Powerplant

In a thermal anti-icing system using engine bleed air, what does the piccolo tube do?

  1. It distributes hot air along the inside of the leading edge Correct answer.
  2. It controls the bleed air pressure at the engine
  3. It measures the outside air temperature
  4. It drains water from the wing structure

Explanation

The piccolo tube is a perforated duct that sprays hot bleed air onto the inner surface of the leading edge. This even distribution prevents local hot spots and ensures effective anti-icing. It does not sense temperature or regulate engine bleed pressure.

Question 37Aircraft General Knowledge - Airframe, Systems and Powerplant

What is the purpose of the air cycle machine in a vapour-cycle air conditioning system?

  1. It stores cooled air for later use
  2. It compresses the refrigerant to raise its temperature
  3. It removes water from the cabin air
  4. It cools the air by expanding it and extracting work Correct answer.

Explanation

In an air cycle system, compressed air is passed through the turbine of the air cycle machine, where it expands and does work, causing a large temperature drop. This is the primary cooling mechanism. Compression of refrigerant belongs to a vapour-cycle system, not the air cycle machine.

Question 38Aircraft General Knowledge - Airframe, Systems and Powerplant

In a cabin pressurisation system, what is the function of the outflow valve?

  1. It admits fresh bleed air into the cabin
  2. It seals the cabin completely during flight
  3. It controls the temperature of the cabin supply air
  4. It regulates the rate at which cabin air leaves, controlling cabin altitude and rate of change Correct answer.

Explanation

The outflow valve modulates the escape of air from the pressurised cabin, thereby controlling cabin pressure and the rate of climb or descent of cabin altitude. Inflow is set by the bleed supply, not by this valve. Temperature control is a separate function.

Question 39Aircraft General Knowledge - Airframe, Systems and Powerplant

What is the purpose of the cabin pressure controller in a pressurisation system?

  1. It controls the cabin temperature
  2. It supplies bleed air to the cabin
  3. It schedules the cabin altitude and rate of change by commanding the outflow valve Correct answer.
  4. It measures the aircraft's altitude above ground

Explanation

The pressure controller compares selected and actual cabin pressure and drives the outflow valve to achieve the desired cabin altitude and rate. It is the brains of the pressurisation system. It does not supply air or control temperature.

Question 40Aircraft General Knowledge - Airframe, Systems and Powerplant

In a four-stroke reciprocating engine, during which stroke is the intake valve open and the piston moving down?

  1. The exhaust stroke
  2. The power stroke
  3. The compression stroke
  4. The induction stroke Correct answer.

Explanation

During the induction stroke the piston moves down and the intake valve is open, drawing the fuel-air mixture into the cylinder. The compression and power strokes occur with both valves closed. The exhaust stroke has the exhaust valve open as the piston moves up.

Question 41Aircraft General Knowledge - Airframe, Systems and Powerplant

What is the purpose of the magneto in a reciprocating engine ignition system?

  1. It regulates the engine oil pressure
  2. It stores fuel for the engine
  3. It controls the pitch of the propeller
  4. It generates the high-tension voltage for the spark plugs independently of the aircraft battery Correct answer.

Explanation

A magneto is a self-contained generator that produces high voltage for the spark plugs, relying on rotating magnets rather than the aircraft battery. This independence provides a reliable ignition source. It does not handle fuel, oil pressure, or propeller pitch.

Question 42Aircraft General Knowledge - Airframe, Systems and Powerplant

Why do most light aircraft reciprocating engines use two magnetos?

  1. To control the fuel-air mixture
  2. To double the engine speed
  3. To provide redundancy and improve combustion by firing two plugs per cylinder Correct answer.
  4. To supply current to the aircraft electrical bus

Explanation

Two magnetos provide independent ignition sources, so the engine continues to run if one fails. They also fire two spark plugs per cylinder, giving more complete and faster combustion. They do not drive the engine speed or supply the electrical bus.

Question 43Aircraft General Knowledge - Airframe, Systems and Powerplant

In a gas turbine engine, what is the function of the compressor?

  1. It accelerates the exhaust gases to produce thrust
  2. It extracts energy from the exhaust to drive the turbine
  3. It mixes fuel with air and ignites it
  4. It raises the pressure of the air before combustion Correct answer.

Explanation

The compressor takes in air and increases its pressure so that combustion can occur efficiently. The turbine extracts energy from the hot gases to drive the compressor. Thrust is produced mainly by the exhaust nozzle and, in bypass engines, the fan.

Question 44Aircraft General Knowledge - Airframe, Systems and Powerplant

What is the purpose of the bypass ratio in a turbofan engine?

  1. It expresses the ratio of exhaust velocity to intake velocity
  2. It expresses the ratio of fuel to air in the combustor
  3. It expresses the ratio of turbine to compressor stages
  4. It expresses the ratio of air bypassing the core to air passing through the core Correct answer.

Explanation

Bypass ratio compares the mass flow of air passing through the fan duct to the mass flow through the engine core. A high bypass ratio generally improves propulsive efficiency and reduces noise. It is not a fuel-air or stage-count ratio.

Question 45Aircraft General Knowledge - Airframe, Systems and Powerplant

In a turboprop engine, what does the propeller governor control?

  1. It varies propeller blade pitch to maintain the selected RPM Correct answer.
  2. It controls the compressor bleed valves
  3. It sets the turbine inlet temperature
  4. It regulates the fuel flow to the combustion chamber

Explanation

The propeller governor senses engine speed and adjusts blade pitch to keep RPM at the selected value as power or airspeed changes. This is the constant-speed propeller principle. Fuel flow and bleed valves are controlled by other systems.

Question 46Aircraft General Knowledge - Airframe, Systems and Powerplant

What is the function of the thrust reverser on a jet engine?

  1. It increases take-off thrust by accelerating the exhaust
  2. It redirects exhaust or fan air forward to produce a decelerating force after landing Correct answer.
  3. It feathers the fan blades to reduce drag
  4. It cools the engine during descent

Explanation

A thrust reverser redirects engine exhaust or fan bypass air forward, producing a rearward force that helps decelerate the aircraft on the runway. It is used after touchdown and is not a thrust-increasing device. It does not cool the engine or feather blades.

Question 47Aircraft General Knowledge - Airframe, Systems and Powerplant

An aircraft experiences a sudden loss of hydraulic system pressure with the gear still retracted. Which design feature is intended to allow gear extension in this situation?

  1. The downlock spring pushing the gear down
  2. The wheel brakes releasing pressure
  3. The normal selector valve operated faster
  4. An emergency extension system using stored pressure or free-fall Correct answer.

Explanation

Certification requires a means of extending the landing gear after a loss of normal hydraulic pressure, typically an accumulator, emergency hand pump, or free-fall mechanism. The downlock spring only holds the gear once it is down; it cannot extend it against air loads. Brakes are unrelated to extension.

Question 48Aircraft General Knowledge - Airframe, Systems and Powerplant

During a dual magneto failure in flight, the engine stops. Which statement best explains why a separate ignition source does not normally exist on a light aircraft?

  1. The engine can run without ignition once warmed up
  2. The magnetos are independent of the battery, so a single electrical failure cannot disable both, but a mechanical failure of both can Correct answer.
  3. The starter motor continues to provide spark in flight
  4. The battery supplies the spark plugs directly, so a dual failure is impossible

Explanation

Magnetos generate their own voltage, so loss of the aircraft electrical system does not stop ignition. However, if both magnetos fail mechanically or their drive fails, no spark is produced and the engine stops. The battery does not feed the plugs, and the starter is not used in flight.

Question 49Flight Performance and Planning

In the landing performance section of an aircraft flight manual, the stated landing distance is normally measured from a point 50 ft above the runway threshold to the point where the aircraft comes to a full stop. Which item does this published distance assume?

  1. A smooth, hard-surfaced runway with full braking applied after touchdown Correct answer.
  2. A dry, level, paved runway with the aircraft at maximum landing mass
  3. A runway with a 2 percent upslope and a tailwind component
  4. A wet runway with reverse thrust and no braking

Explanation

Certificated landing distances are based on a smooth, hard, dry surface, standard technique and maximum braking after crossing the threshold at 50 ft. They do not include reverse thrust, slope or wind benefits, and they are quoted for the maximum landing mass. Any operational factor must be applied by the pilot on top of the manual figure.

Question 50Flight Performance and Planning

An aircraft has a take-off ground roll of 640 m in still air at sea level. Using the usual approximation that ground roll varies with the square of the true airspeed, what ground roll should be expected in a 10 kt headwind if the still-air lift-off speed is 60 kt?

  1. 640 m
  2. 460 m Correct answer.
  3. 400 m
  4. 470 m

Explanation

The headwind reduces the ground speed at lift-off from 60 kt to 50 kt, so the distance scales by (50/60) squared, which is 0.694. Multiplying 640 m by 0.694 gives about 444 m, and the closest listed value is 460 m. The exact value depends on thrust and acceleration effects, so a small margin is realistic.