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JCAA ATPL Theory study materials
JCAA ATPL Theory study resources

JCAA ATPL Theory practice questions

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Question 1Air Law and ATC Procedures

Under the ICAO Convention on International Civil Aviation (Chicago Convention), which document is issued by a contracting State to certify that an aircraft is fit for flight and complies with applicable airworthiness requirements?

  1. Certificate of Registration
  2. Crew Member Licence
  3. Air Operator Certificate
  4. Certificate of Airworthiness Correct answer.

Explanation

The Certificate of Airworthiness is the document confirming that the individual aircraft meets the airworthiness requirements of the State of Registry and is fit for flight. The Certificate of Registration merely records ownership/nationality, while the Air Operator Certificate authorises the operator's commercial activities.

Question 2Air Law and ATC Procedures

An aircraft is registered in State A but operated on a lease by an operator in State B. Which State is responsible for issuing and maintaining the aircraft's Certificate of Airworthiness in the normal case?

  1. The State of Design
  2. The State of Registry Correct answer.
  3. The State of the Operator
  4. The State of Manufacture

Explanation

Under the Chicago Convention, the State of Registry is responsible for the airworthiness of the aircraft and for issuing its Certificate of Airworthiness. Transfer of certain functions to the State of the Operator is possible only through a formal agreement notified to ICAO, so the default rule is the State of Registry.

Question 3Air Law and ATC Procedures

Which body of ICAO adopts Standards and Recommended Practices (SARPs) and incorporates them as Annexes to the Chicago Convention?

  1. The ICAO Assembly
  2. The Air Navigation Commission
  3. The Legal Committee
  4. The ICAO Council Correct answer.

Explanation

The ICAO Council, meeting under Article 54 of the Convention, is empowered to adopt and amend Annexes containing SARPs. The Assembly is the sovereign body but does not itself adopt Annexes, and the Air Navigation Commission only provides technical recommendations.

Question 4Air Law and ATC Procedures

A pilot holds a Private Pilot Licence (Aeroplane). Under the standard ICAO framework, which activity is permitted without holding a higher-grade licence?

  1. Acting as pilot-in-command of an aeroplane carrying passengers for private purposes without remuneration Correct answer.
  2. Flying for remuneration as pilot-in-command of a commercial air transport flight
  3. Receiving payment for instructing student pilots
  4. Acting as co-pilot on a scheduled international passenger service

Explanation

A PPL permits the holder to act as pilot-in-command of aircraft in non-commercial operations, including carrying passengers privately without remuneration. Commercial air transport and paid instruction require a commercial or higher licence with the appropriate ratings.

Question 5Air Law and ATC Procedures

An applicant for a Commercial Pilot Licence (Aeroplane) must normally have completed at least how many total flying hours under the ICAO minimum standard?

  1. 150 hours
  2. 300 hours
  3. 250 hours
  4. 200 hours Correct answer.

Explanation

ICAO Annex 1 establishes a minimum of 200 hours total flight time for the issue of a CPL, distributed across dual, solo, cross-country and instrument experience. Individual States may impose higher requirements, but 200 hours is the international baseline.

Question 6Air Law and ATC Procedures

Which medical certificate class is normally required for a pilot exercising the privileges of a Commercial Pilot Licence?

  1. Class 2
  2. Class 1 Correct answer.
  3. Class 3
  4. No medical certificate is required

Explanation

Commercial pilots and airline transport pilots must hold a valid Class 1 medical certificate under Annex 1. Class 2 applies to private pilots, and Class 3 is associated with air traffic controllers in some States.

Question 7Air Law and ATC Procedures

A flight crew member's licence includes a type rating for a multi-pilot aeroplane. What does this rating authorise?

  1. To instruct on that type without further qualification
  2. To act as pilot on that specific type of aeroplane, subject to the privileges of the licence Correct answer.
  3. To conduct maintenance on that type of aeroplane
  4. To act as pilot on any aeroplane of the same manufacturer

Explanation

A type rating is specific to the aircraft type and permits the holder to act as a flight crew member on that type, within the privileges of the underlying licence. It does not extend to other types, to maintenance, or to instruction.

Question 8Air Law and ATC Procedures

Which document contains the Standards and Recommended Practices relating to Rules of the Air?

  1. Annex 14
  2. Annex 6
  3. Annex 2 Correct answer.
  4. Annex 11

Explanation

ICAO Annex 2 contains the Rules of the Air, including right-of-way, cruising levels and signals. Annex 6 covers operation of aircraft, Annex 11 air traffic services, and Annex 14 aerodromes.

Question 9Air Law and ATC Procedures

Two aircraft are approaching head-on at approximately the same altitude. According to the Rules of the Air, what action must each take?

  1. Both climb to the right
  2. Both alter heading to the left
  3. Both alter heading to the right Correct answer.
  4. The lower aircraft gives way by descending

Explanation

When two aircraft are approaching head-on or nearly so, each shall alter its heading to the right to pass well clear. This rule applies regardless of aircraft category and is designed to produce a predictable separation.

Question 10Air Law and ATC Procedures

An aircraft on approach to land has the right of way over other aircraft in flight or on the ground, provided it is at what stage?

  1. When it is at or below 1,000 ft above aerodrome level
  2. When it is within 10 NM of the aerodrome
  3. When it is on final approach to land Correct answer.
  4. When it has been cleared to land by ATC

Explanation

Under the Rules of the Air, an aircraft on final approach to land has the right of way over other aircraft in flight or on the ground. The priority arises from being on final approach, not from a specific distance, altitude or clearance.

Question 11Air Law and ATC Procedures

An aircraft is being overtaken by another aircraft. Which aircraft has the right of way, and what must the overtaking aircraft do?

  1. The aircraft being overtaken has right of way; the overtaking aircraft must keep clear Correct answer.
  2. The faster aircraft has right of way regardless of position
  3. Both must alter course to the right simultaneously
  4. The overtaking aircraft has right of way; the other must maintain speed

Explanation

The aircraft being overtaken has the right of way, and the overtaking aircraft must keep well clear by altering heading to the right until entirely past and clear. Speed or performance does not confer priority.

Question 12Air Law and ATC Procedures

In an emergency, what is the meaning of the radiotelephony signal 'MAYDAY'?

  1. An urgency signal concerning the safety of an aircraft but without immediate danger
  2. A request for a radio check on the current frequency
  3. A distress signal indicating grave and imminent danger requiring immediate assistance Correct answer.
  4. A signal that the aircraft is being unlawfully interfered with

Explanation

MAYDAY is the international distress signal and indicates that an aircraft is threatened by grave and imminent danger and requires immediate assistance. The urgency signal is PAN PAN, which concerns safety but not immediate distress.

Question 13Air Law and ATC Procedures

An aircraft transmits 'PAN PAN, PAN PAN, PAN PAN'. Under the radiotelephony procedures, this indicates what?

  1. A routine request to change frequency
  2. An urgency situation concerning the safety of an aircraft or person Correct answer.
  3. A distress situation requiring immediate assistance
  4. A test transmission on the distress frequency

Explanation

PAN PAN is the urgency signal, used when the safety of an aircraft or person is concerned but immediate assistance is not yet required. Distress, with grave and imminent danger, uses MAYDAY.

Question 14Air Law and ATC Procedures

Which of the following correctly describes a 'readback' requirement in ATC communications?

  1. The pilot confirms receipt by transmitting only the word 'roger'
  2. The pilot writes the clearance in the technical log after landing
  3. The controller repeats the pilot's request before issuing a clearance
  4. The pilot repeats the controller's instruction to allow the controller to verify it Correct answer.

Explanation

A readback requires the pilot to repeat the safety-related elements of a clearance or instruction so that the controller can verify correct reception. Merely saying 'roger' does not constitute a readback for safety-critical items.

Question 15Air Law and ATC Procedures

In the standard phonetic alphabet, which word represents the letter 'Q'?

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

Explanation

The ICAO phonetic alphabet uses 'Quebec' for the letter Q. Using the standard word avoids confusion between similar-sounding letters on the radio.

Question 16Air Law and ATC Procedures

An aircraft is flying under Instrument Flight Rules (IFR) in controlled airspace. Which statement correctly describes the clearance requirement?

  1. The aircraft must obtain an ATC clearance before entering controlled airspace Correct answer.
  2. The aircraft may enter without clearance provided it remains clear of cloud
  3. The aircraft needs a clearance only when flying above FL200
  4. The aircraft only needs to advise ATC after entry

Explanation

IFR flights in controlled airspace require an ATC clearance before entry, and the flight must comply with the terms of that clearance. Remaining clear of cloud does not substitute for a clearance in controlled airspace.

Question 17Air Law and ATC Procedures

What does an ATC clearance normally do?

  1. Authorises a flight to proceed under specified conditions Correct answer.
  2. Transfers responsibility for terrain clearance to the controller
  3. Confirms that the aircraft is airworthy for the flight
  4. Guarantees that the flight will be free of all other traffic

Explanation

An ATC clearance authorises a flight to proceed under specified conditions and is based on known traffic. It does not relieve the pilot of responsibility for terrain clearance, airworthiness, or vigilance.

Question 18Air Law and ATC Procedures

In a radar-controlled environment, what does the instruction 'Squawk 7000' require the pilot to do?

  1. Change to the emergency frequency 121.5 MHz
  2. Set the transponder to code 7000 Correct answer.
  3. Select altitude reporting mode on the transponder
  4. Contact the aerodrome control tower on 118.7 MHz

Explanation

'Squawk 7000' instructs the pilot to select the four-digit code 7000 on the transponder. The code itself does not change communication frequencies; it identifies the aircraft to the radar controller.

Question 19Air Law and ATC Procedures

An aircraft has suffered a radio communication failure in IMC and is being operated under IFR. What is the standard initial action under the Rules of the Air?

  1. Continue on the last acknowledged clearance and attempt to re-establish communication Correct answer.
  2. Turn back to the departure aerodrome without further action
  3. Squawk 7500 and continue as cleared
  4. Immediately descend below cloud and continue visually

Explanation

When radio communication fails in IMC, the pilot should continue on the last acknowledged clearance or routing and attempt to re-establish communication. The transponder should be set to the appropriate code (7600), not 7500, which denotes unlawful interference.

Question 20Air Law and ATC Procedures

Which transponder code indicates unlawful interference with an aircraft?

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

Explanation

Code 7500 is the special code for unlawful interference. Code 7600 denotes radio communication failure and 7700 denotes a general emergency.

Question 21Air Law and ATC Procedures

In which airspace class is IFR and VFR flight permitted, with all aircraft subject to ATC clearance and separation provided to all aircraft?

  1. Class F
  2. Class B Correct answer.
  3. Class G
  4. Class E

Explanation

Class B airspace permits both IFR and VFR flights, all of which require an ATC clearance, and ATC provides separation to all aircraft. Class E separates IFR from IFR and from VFR only where practicable, and Class G is uncontrolled.

Question 22Air Law and ATC Procedures

What is the purpose of a Mandatory Occurrence Report in the context of safety management?

  1. To record occurrences that could affect safety so lessons can be learned Correct answer.
  2. To provide evidence for insurance claims only
  3. To serve as a substitute for the aircraft technical log
  4. To allocate blame to the crew responsible

Explanation

A Mandatory Occurrence Report is a safety-reporting mechanism intended to identify hazards and prevent recurrence, not to assign blame. The information supports safety analysis and the development of mitigating measures.

Question 23Air Law and ATC Procedures

An operator's Safety Management System (SMS) includes a formal process for identifying hazards and assessing risk. Which component of an SMS is this?

  1. Safety risk management Correct answer.
  2. Safety assurance
  3. Emergency response planning
  4. Safety promotion

Explanation

Safety risk management encompasses hazard identification and risk assessment and mitigation. Safety assurance monitors performance, safety promotion covers training and communication, and emergency response planning is a separate element.

Question 24Air Law and ATC Procedures

An aircraft is involved in a serious incident. Under the usual framework, which State is responsible for instituting the investigation?

  1. The State of Design only
  2. The State of Manufacture only
  3. The State whose airspace the aircraft was overflying only
  4. The State of Registry or the State of the Operator Correct answer.

Explanation

Under Annex 13, the State of Registry or the State of the Operator, as appropriate, is normally responsible for instituting the investigation. The State of Occurrence may delegate, and other States may participate as accredited representatives.

Question 25Aircraft General Knowledge (Airframe, Systems, Powerplant, Electrics)

On a transport aeroplane, the primary structural function of the wing spar is to carry which loads?

  1. Bending moments generated by lift and weight distribution Correct answer.
  2. Cabin pressurisation differential pressure
  3. Engine thrust reactions transmitted from the pylons
  4. Torsion produced only by aileron deflection

Explanation

Spars are the main bending members of the wing, running spanwise with flanges and webs sized to resist the bending moment created by lift acting outboard and weight acting inboard. Torsion is carried mainly by the torsion box formed by the skin, ribs and spar webs, not by the spar alone.

Question 26Aircraft General Knowledge (Airframe, Systems, Powerplant, Electrics)

Which material property makes carbon fibre reinforced plastic attractive for primary airframe structure?

  1. High thermal conductivity for heat dissipation
  2. Isotropic stiffness identical in all directions
  3. Ability to deform plastically before failure
  4. High specific strength with good fatigue resistance Correct answer.

Explanation

CFRP offers high strength and stiffness per unit mass and, unlike metals, shows very good fatigue behaviour because cracks are not propagated through fibres in the same way as in aluminium. This allows weight savings in primary structure such as wing skins and tailplanes.

Question 27Aircraft General Knowledge (Airframe, Systems, Powerplant, Electrics)

In a semi-monocoque fuselage, what is the role of the stringers?

  1. They carry the pressurisation loads alone without the skin
  2. They resist hoop stress only in the nose section
  3. They form the primary attachment for the wing spar
  4. They stiffen the skin and carry longitudinal bending loads Correct answer.

Explanation

Stringers run lengthwise, stiffening the skin against buckling and sharing longitudinal bending with the skin, while frames maintain the cross-sectional shape. The skin itself carries most of the shear and pressurisation loads in a semi-monocoque design.

Question 28Aircraft General Knowledge (Airframe, Systems, Powerplant, Electrics)

A hydraulic system uses a constant-pressure variable-displacement pump. When system demand falls to zero, what does the pump do?

  1. Destrokes to near-zero displacement while maintaining set pressure Correct answer.
  2. Increases displacement to build a pressure reserve
  3. Continues at full displacement and bypasses fluid to the reservoir
  4. Stops rotating until pressure drops below a threshold

Explanation

A variable-displacement pump with a pressure compensator reduces its swashplate angle as pressure reaches the set value, so flow falls to nearly zero while pressure is maintained. This limits heat generation and power draw compared with a fixed-displacement pump.

Question 29Aircraft General Knowledge (Airframe, Systems, Powerplant, Electrics)

What is the purpose of a hydraulic accumulator in an aircraft system?

  1. To cool the fluid before it returns to the reservoir
  2. To filter contamination from the return line
  3. To store pressurised fluid for peak demands and damp pressure surges Correct answer.
  4. To convert hydraulic pressure into electrical power

Explanation

An accumulator contains a gas-charged chamber separated from the fluid; it absorbs pressure fluctuations, supplies extra flow during transient high demand, and provides a limited reserve for emergency operation. It does not perform filtration or cooling.

Question 30Aircraft General Knowledge (Airframe, Systems, Powerplant, Electrics)

In a typical transport aircraft hydraulic system, how is a hydraulic fuse (line rupture valve) intended to operate?

  1. It shuts off flow when the volume passing exceeds a set limit Correct answer.
  2. It regulates downstream pressure to a fixed value
  3. It prevents reverse flow back to the pump
  4. It opens to relieve overpressure into the return line

Explanation

A hydraulic fuse senses the volume of fluid passing through it and closes when this exceeds a preset value, isolating a downstream leak from the rest of the system and preserving fluid for other consumers. It is a volumetric device, not a pressure regulator.

Question 31Aircraft General Knowledge (Airframe, Systems, Powerplant, Electrics)

Which statement correctly describes the function of a spoiler on a swept wing during roll control?

  1. It acts purely as a speed brake with no roll effect
  2. It spoils lift on one wing, creating a rolling moment and aiding drag rise Correct answer.
  3. It increases lift on one wing to raise that wing
  4. It increases the critical Mach number of the wing

Explanation

Raising a spoiler destroys lift on that wing and adds drag, so the wing drops and the aircraft rolls towards the spoiler; spoilers are often used in conjunction with ailerons for roll control. They do not generate lift and do not raise the wing on which they are deployed.

Question 32Aircraft General Knowledge (Airframe, Systems, Powerplant, Electrics)

What is the purpose of a yaw damper in an aircraft with a swept wing?

  1. To apply automatic rudder deflection opposing Dutch roll Correct answer.
  2. To provide artificial feel in the pitch channel
  3. To trim the aircraft in pitch during flap extension
  4. To limit rudder deflection at high speed only

Explanation

A yaw damper senses yaw rate and commands rudder movement to oppose the oscillation, suppressing Dutch roll, which is more pronounced on swept wings. It operates continuously in flight and is separate from rudder travel limiting or pitch trim.

Question 33Aircraft General Knowledge (Airframe, Systems, Powerplant, Electrics)

A powered flying control system with irreversible hydraulic actuators requires artificial feel because:

  1. the hydraulic fluid becomes compressible at altitude
  2. the pilot no longer senses aerodynamic hinge moments through the controls Correct answer.
  3. the autopilot requires a feedback signal
  4. the control surfaces become heavier as speed decreases

Explanation

With an irreversible actuator, aerodynamic loads on the surface are not fed back to the control column, so the pilot would have no natural cue of speed or load. Artificial feel units generate a simulated force that increases with speed and control deflection.

Question 34Aircraft General Knowledge (Airframe, Systems, Powerplant, Electrics)

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

  1. To cool the air before it enters the combustion chamber
  2. To increase air velocity for better fuel mixing
  3. To drive the accessory gearbox
  4. To reduce air velocity and increase static pressure before combustion Correct answer.

Explanation

The diffuser converts kinetic energy of the high-velocity compressor delivery air into static pressure by slowing the flow, providing the pressure rise needed for efficient combustion with acceptable pressure loss. It does not cool the air or drive accessories.

Question 35Aircraft General Knowledge (Airframe, Systems, Powerplant, Electrics)

Why is a dual-spool (two-shaft) compressor arrangement used in many turbofan engines?

  1. Each spool can run at its optimum speed, improving surge margin and efficiency Correct answer.
  2. It eliminates the need for a combustion chamber
  3. It removes the requirement for a turbine
  4. It allows the fan to be driven without a shaft

Explanation

Separating the compression into low-pressure and high-pressure spools lets each rotate at a speed matched to its blade design, avoiding the compromise of a single shaft and improving stall/surge margins and efficiency. Both spools still require turbines to drive them.

Question 36Aircraft General Knowledge (Airframe, Systems, Powerplant, Electrics)

What happens to the compressor surge margin if the engine is accelerated too rapidly from idle?

  1. It increases because fuel flow is limited
  2. It increases, improving acceleration
  3. It remains unchanged because airflow is constant
  4. It decreases, increasing the risk of compressor stall or surge Correct answer.

Explanation

Rapid throttle movement schedules a large fuel increase before airflow can follow, raising the pressure ratio across the compressor stages and reducing the stall margin. Fuel control units therefore incorporate acceleration schedules and surge bleeds to avoid this.

Question 37Aircraft General Knowledge (Airframe, Systems, Powerplant, Electrics)

In a high-bypass turbofan, which statement about the bypass ratio is correct?

  1. It is the turbine inlet temperature divided by the compressor outlet temperature
  2. It is the fan pressure ratio multiplied by the core pressure ratio
  3. It is the exhaust velocity divided by the intake velocity
  4. It is the mass flow through the bypass duct divided by the mass flow through the core Correct answer.

Explanation

Bypass ratio compares the mass of air passing through the fan duct outside the core with the mass passing through the engine core. High bypass ratios give better propulsive efficiency and lower specific fuel consumption at typical cruise speeds.

Question 38Aircraft General Knowledge (Airframe, Systems, Powerplant, Electrics)

What is the primary purpose of the fan in a high-bypass turbofan?

  1. To drive the accessory gearbox
  2. To cool the turbine blades
  3. To compress air to the highest possible pressure for combustion
  4. To accelerate a large mass of air to a modest velocity for thrust Correct answer.

Explanation

A large-diameter fan moves a high mass flow at relatively low velocity; propulsive efficiency is best when a large mass is accelerated only slightly. Core compression to high pressure is the task of the HP compressor.

Question 39Aircraft General Knowledge (Airframe, Systems, Powerplant, Electrics)

Which of the following is the correct description of the Brayton (constant-pressure) cycle as applied to a gas turbine?

  1. Constant-volume heat addition with adiabatic expansion only
  2. Adiabatic compression, constant-pressure heat addition, adiabatic expansion, constant-pressure heat rejection Correct answer.
  3. Constant-pressure compression with constant-volume combustion and no exhaust stroke
  4. Isothermal compression followed by isothermal expansion

Explanation

The gas turbine cycle consists of compression, heat addition at essentially constant pressure in the combustor, expansion through the turbine, and heat rejection to atmosphere. The ideal cycle assumes adiabatic compression and expansion, with pressure losses in the combustor neglected.

Question 40Aircraft General Knowledge (Airframe, Systems, Powerplant, Electrics)

What is the main function of the lubrication system in a gas turbine engine?

  1. To reduce friction and remove heat from bearings and gears Correct answer.
  2. To provide hydraulic power for the landing gear
  3. To increase the octane rating of the fuel
  4. To seal the combustion chamber against gas leakage

Explanation

Turbine engine oil lubricates and cools the main bearings and accessory drives, carries away heat, and protects against corrosion. It also helps seal bearing chambers, but its primary role is lubrication and heat removal.

Question 41Aircraft General Knowledge (Airframe, Systems, Powerplant, Electrics)

In a turbine engine, what is the purpose of the fuel-oil heat exchanger?

  1. To cool the fuel using ram air before it reaches the injectors
  2. To separate water from the fuel
  3. To increase fuel pressure to the HP pump
  4. To cool the engine oil using fuel while warming the fuel for better combustion Correct answer.

Explanation

The fuel-oil heat exchanger transfers heat from the engine oil to the fuel, cooling the oil and warming the fuel, which improves atomisation and prevents ice formation. It does not separate water or raise fuel pressure.

Question 42Aircraft General Knowledge (Airframe, Systems, Powerplant, Electrics)

What is the significance of the engine pressure ratio (EPR) as a thrust parameter?

  1. It is the ratio of bypass to core airflow
  2. It compares turbine discharge pressure to compressor inlet pressure and reflects thrust Correct answer.
  3. It measures the fuel flow divided by the compressor speed
  4. It indicates the oil pressure relative to fuel pressure

Explanation

EPR is the ratio of turbine discharge (exhaust) pressure to compressor inlet pressure and correlates closely with thrust, so it is used as the primary thrust setting parameter on many engines. It is independent of fuel flow and oil pressure.

Question 43Aircraft General Knowledge (Airframe, Systems, Powerplant, Electrics)

In a DC electrical system, what is the function of a shunt in the battery circuit?

  1. To store energy for emergency use
  2. To reverse the polarity of the battery
  3. To provide a small voltage proportional to current for indication and control Correct answer.
  4. To limit the charging current to the battery

Explanation

A shunt is a low-resistance element that develops a small voltage drop proportional to the current flowing through it, allowing the ammeter or current-sensing circuit to measure large currents. It does not itself limit current or store energy.

Question 44Aircraft General Knowledge (Airframe, Systems, Powerplant, Electrics)

Which statement about a nickel-cadmium (NiCd) battery is correct?

  1. Its terminal voltage remains nearly constant until almost fully discharged Correct answer.
  2. It requires no ventilation during charging
  3. It cannot be recharged in situ
  4. Its terminal voltage falls linearly from the moment discharge begins

Explanation

NiCd cells have a flat discharge characteristic, holding close to nominal voltage for most of the discharge before dropping sharply near the end. Charging must be controlled and vented because overcharging produces gas.

Question 45Aircraft General Knowledge (Airframe, Systems, Powerplant, Electrics)

What is the purpose of a reverse-current cut-out in a DC generator circuit?

  1. To reverse the field current to increase output
  2. To disconnect the generator if current flows from the battery into the generator Correct answer.
  3. To cut out the battery during engine start
  4. To protect the generator from overvoltage only

Explanation

If a generator's output falls below battery voltage, current would flow back from the battery and motor the generator, damaging it. The reverse-current cut-out opens the circuit when this reverse flow is detected.

Question 46Aircraft General Knowledge (Airframe, Systems, Powerplant, Electrics)

An aircraft has a 28 V DC system with a 200 A generator. What is the approximate maximum electrical power available from this generator?

  1. 5.6 kW Correct answer.
  2. 56 kW
  3. 560 W
  4. 0.14 kW

Explanation

Electrical power is the product of voltage and current, so 28 V multiplied by 200 A gives 5,600 W, which is 5.6 kW. The other figures result from misplacing the decimal point or dividing instead of multiplying.

Question 47Aircraft General Knowledge (Airframe, Systems, Powerplant, Electrics)

Why is a constant-frequency AC system often replaced by a variable-frequency (VF) system on modern aircraft?

  1. It eliminates the need for any generator
  2. It removes the need for a hydromechanical constant-speed drive and improves reliability Correct answer.
  3. It allows the use of DC motors only
  4. It removes the need for circuit protection

Explanation

Variable-frequency generators produce AC at a frequency that varies with engine speed, so the heavy, maintenance-intensive constant-speed drive unit is not needed. Power is converted as required by transformer-rectifier units and inverters for constant-frequency loads.

Question 48Aircraft General Knowledge (Airframe, Systems, Powerplant, Electrics)

What is the purpose of the fire detection loop in an engine nacelle?

  1. To extinguish the fire automatically without crew action
  2. To vent smoke overboard
  3. To sense a temperature rise or rate of rise and trigger a warning Correct answer.
  4. To shut down the engine directly

Explanation

Engine fire detection loops sense local temperature or rate of temperature rise and provide a warning to the flight deck, allowing the crew to discharge the extinguisher and shut down the engine. Detection and extinguishing are separate systems.

Question 49Flight Performance and Planning (Mass and Balance, Performance, Flight Planning)

An aircraft has a basic empty mass of 9 000 kg and a maximum zero-fuel mass of 15 000 kg. With a traffic load of 4 500 kg, what is the maximum fuel that may be loaded if the take-off mass limit of 20 000 kg is not to be exceeded?

  1. 6 500 kg Correct answer.
  2. 6 000 kg
  3. 5 500 kg
  4. 5 000 kg

Explanation

Zero-fuel mass with the given traffic load is 9 000 + 4 500 = 13 500 kg, which is below the 15 000 kg MZFM, so the ZFM limit is not critical. The take-off mass limit then governs: 20 000 − 13 500 = 6 500 kg of fuel. The more restrictive of the two limits must always be used.

Question 50Flight Performance and Planning (Mass and Balance, Performance, Flight Planning)

Which statement correctly describes the effect of a forward centre of gravity on an aeroplane in flight?

  1. Longitudinal stability is unaffected but the rate of climb improves.
  2. Longitudinal stability increases and the stalling speed decreases.
  3. Longitudinal stability increases and elevator effectiveness to raise the nose is reduced. Correct answer.
  4. Longitudinal stability decreases and the stalling speed increases.

Explanation

Moving the centre of gravity forward increases the distance between the centre of gravity and the tailplane, which increases the restoring moment and therefore longitudinal stability. At the same time the nose-up authority available from the elevator is reduced, which raises the rotation and flare forces required and lengthens the take-off run.