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CARC ATPL Theory practice questions

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Question 1Air Law

Under the Convention on International Civil Aviation (Chicago Convention), what is the status of the Annexes adopted by the ICAO Council?

  1. They are standards and recommended practices that contracting states must notify ICAO of any differences from. Correct answer.
  2. They are recommendations that states may adopt voluntarily with no obligation to notify differences.
  3. They apply only to states that have signed a separate bilateral agreement with ICAO.
  4. They are binding on all contracting states without any notification procedure.

Explanation

Article 37 of the Chicago Convention empowers ICAO to adopt international standards and recommended practices (SARPs) as Annexes. Under Article 38, any contracting state that finds it impracticable to comply with an international standard must notify ICAO of the differences. The Annexes are therefore not automatically binding in every detail without notification.

Question 2Air Law

An aircraft registered in State A is operated by an air operator certificate holder from State B on a flight between two points in State C. Which state exercises primary jurisdiction over the aircraft's airworthiness and crew licensing?

  1. State C, the state of the territory overflown
  2. ICAO, through its regional office
  3. State B, the state of the operator
  4. State A, the state of registry Correct answer.

Explanation

Under the Chicago Convention, the state of registry is responsible for the airworthiness of the aircraft and for the licensing of its crew. The state of the operator may have additional obligations under Annex 6, but the primary legal jurisdiction for airworthiness and crew licensing rests with the state of registry. The state of overflight does not assume these responsibilities.

Question 3Air Law

What is the minimum age for the issue of a commercial pilot licence (CPL) under ICAO Annex 1?

  1. 16 years
  2. 18 years Correct answer.
  3. 21 years
  4. 17 years

Explanation

ICAO Annex 1 specifies that an applicant for a commercial pilot licence shall be at least 18 years of age. This aligns with the minimum age for an airline transport pilot licence, while a private pilot licence may be issued at 17. The age requirement is a standard that contracting states implement in their national licensing rules.

Question 4Air Law

Under ICAO Annex 1, what is the validity period of a Class 1 medical certificate for a pilot who is under 40 years of age and engaged in single-pilot commercial air transport operations carrying passengers?

  1. 24 months
  2. 12 months
  3. 36 months
  4. 6 months Correct answer.

Explanation

Annex 1 specifies that for pilots engaged in single-pilot commercial air transport operations carrying passengers, the Class 1 medical certificate is valid for 6 months. For other commercial operations the period may be 12 months, and for pilots under 40 in multi-pilot operations it may be 12 months. The 6-month rule applies specifically to the single-pilot passenger-carrying case.

Question 5Air Law

An operator's aircraft is due for a scheduled maintenance check. Under ICAO Annex 6, Part I, which document must the operator use to ensure that maintenance is performed and recorded in accordance with an approved maintenance programme?

  1. The maintenance control manual Correct answer.
  2. The aircraft flight manual
  3. The minimum equipment list
  4. The operations manual

Explanation

Annex 6, Part I requires the operator to provide a maintenance control manual for the use and guidance of maintenance personnel. This manual describes the procedures for maintaining the aircraft, including the approved maintenance programme and records. The flight manual, operations manual and MEL serve different purposes.

Question 6Air Law

In the event of an unlawful interference with an aircraft in flight, which state is primarily responsible for instituting criminal proceedings against the alleged offender if that state has custody of the person?

  1. The state of registration of the aircraft
  2. The state of landing where the offender disembarks
  3. The state of the operator's principal place of business
  4. The state in whose territory the offender is found Correct answer.

Explanation

Under the Tokyo Convention, the state in whose territory the alleged offender is found must, if it does not extradite the person, submit the case to its competent authorities for prosecution. This principle of aut dedere aut judicare is central to the convention. The state of registration and the state of landing have other obligations, such as restoring control of the aircraft.

Question 7Air Law

Under the Chicago Convention, what is required for a scheduled international air service to operate over or into the territory of a contracting state?

  1. Only a notification to ICAO of the intended schedule.
  2. A special permission or other authorization from that state, and compliance with the terms of the Chicago Convention. Correct answer.
  3. A bilateral agreement with the state of registry only.
  4. No permission is required because the Air Transit Agreement grants automatic overflight rights.

Explanation

Article 6 of the Chicago Convention states that no scheduled international air service may be operated over or into the territory of a contracting state except with the special permission or other authorization of that state. This is the legal basis for bilateral air services agreements. The Air Transit Agreement provides certain transit rights only among its parties, not a universal automatic right.

Question 8Air Law

Which document issued under the Chicago Convention contains the Standards and Recommended Practices for aircraft nationality and registration marks?

  1. Annex 8
  2. Annex 7 Correct answer.
  3. Annex 6
  4. Annex 1

Explanation

ICAO Annex 7 is titled Aircraft Nationality and Registration Marks and contains the SARPs for marking aircraft. Annex 1 deals with personnel licensing, Annex 6 with operation of aircraft, and Annex 8 with airworthiness of aircraft. Knowing the Annex numbering is a common requirement in air law examinations.

Question 9Air Law

An aircraft is forced to land in a contracting state because of a mechanical emergency. Under Article 25 of the Chicago Convention, what must the state do?

  1. Provide measures to assist the aircraft and protect its occupants and cargo. Correct answer.
  2. Detain the aircraft until the operator pays landing and parking fees.
  3. Confiscate the aircraft pending investigation by the state of registry.
  4. Require the aircraft to be dismantled and removed by the operator.

Explanation

Article 25 of the Chicago Convention requires contracting states to provide such measures of assistance to aircraft in distress in their territory as may be practicable, and to permit the owners or authorities of the state of registry to provide measures of assistance under proper supervision. The focus is on assistance and protection, not detention or confiscation.

Question 10Air Law

Under ICAO Annex 2, what is the meaning of the term 'air traffic control clearance'?

  1. Advice provided by ATC to assist a pilot in the safe conduct of flight.
  2. Permission for an aircraft to enter a control zone without radio communication.
  3. Authorization for an aircraft to proceed under conditions specified by an air traffic control unit. Correct answer.
  4. A notification that an aircraft's flight plan has been received by the unit.

Explanation

Annex 2 defines an air traffic control clearance as an authorization for an aircraft to proceed under conditions specified by an air traffic control unit. It is distinct from a flight information service, which provides advice and information. A clearance does not relieve the pilot from responsibility for the safety of the flight.

Question 11Air Law

In which circumstances may an aircraft be operated in the territory of a contracting state without a certificate of airworthiness, according to Annex 8?

  1. When the operator has obtained insurance covering airworthiness defects.
  2. When the state of registry has issued a special flight permit or equivalent document. Correct answer.
  3. When the flight is a private flight of less than 30 minutes' duration.
  4. When the aircraft is flown by a pilot holding an airline transport pilot licence.

Explanation

Annex 8 permits flight without a normal certificate of airworthiness when a special flight permit or equivalent document has been issued by the state of registry for a specific purpose, such as a ferry flight for maintenance. The permit is subject to conditions that ensure safety. Insurance or pilot licence type does not substitute for this authorization.

Question 12Air Law

Which body of ICAO is responsible for adopting and amending the Annexes to the Chicago Convention?

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

Explanation

Under Article 37 and Article 54 of the Chicago Convention, the ICAO Council adopts and amends the Annexes. The Air Navigation Commission reviews and recommends technical amendments, but the formal adoption is by the Council. The Assembly is the sovereign body but does not adopt Annexes directly.

Question 13Air Law

A pilot operating a commercial air transport flight experiences a serious incident. Under ICAO Annex 13, which state is responsible for instituting the investigation?

  1. The state in which the serious incident occurred. Correct answer.
  2. The state of manufacture of the aircraft.
  3. The state of registry, because the aircraft is registered there.
  4. The state of the operator, regardless of where the incident occurred.

Explanation

Annex 13 establishes that the state in which an accident or serious incident occurs is responsible for instituting the investigation. Other states, such as the state of registry, state of the operator, state of design and state of manufacture, may participate as accredited representatives. This ensures that the investigation is conducted where the evidence is located.

Question 14Air Law

Under the Convention on the Suppression of Unlawful Acts against the Safety of Civil Aviation (Montreal Convention 1971), which act constitutes an offence?

  1. Smoking in an aircraft lavatory contrary to company policy.
  2. Failing to present a valid passport on arrival at an international airport.
  3. Refusing to comply with a lawful instruction from a cabin crew member.
  4. Communicating false information in a way that endangers the safety of an aircraft in flight. Correct answer.

Explanation

The Montreal Convention 1971, as supplemented by the 1988 Protocol, makes it an offence to communicate information known to be false in a way that endangers the safety of an aircraft in flight. The other options are regulatory or administrative matters, not offences under this convention. The convention addresses acts of violence and sabotage against civil aviation.

Question 15Air Law

What is the requirement for a contracting state under Article 12 of the Chicago Convention regarding rules of the air?

  1. Each state may apply its own rules without regard to ICAO standards.
  2. States must adopt the rules of the state of registry for all foreign aircraft.
  3. States must ensure that their rules of the air conform to the standards and practices established under the Convention. Correct answer.
  4. States must delegate rule-making authority to ICAO.

Explanation

Article 12 requires contracting states to adopt measures to ensure that every aircraft flying over or within their territory complies with the rules in force there, and to keep their own rules of the air in conformity with the standards and practices established under the Convention. This promotes uniformity of air navigation. States retain sovereignty but must align their rules with ICAO standards.

Question 16Air Law

Under ICAO Annex 2, an aircraft is considered to be in flight from the moment when, for the purpose of flight, it first moves under its own power. When does the aircraft cease to be in flight?

  1. When it taxis off the runway after landing.
  2. When the engines are shut down after landing. Correct answer.
  3. When the pilot signs the aircraft technical log after the flight.
  4. When it lands and comes to rest on the ground.

Explanation

Annex 2 defines the period of flight as beginning when the aircraft first moves under its own power for the purpose of flight and ending when it comes to rest at the end of the flight and the engines are shut down. The key event is the shutdown of engines after coming to rest, not merely touching down or taxiing. This definition matters for applying rules of the air and accident reporting.

Question 17Aircraft General Knowledge - Airframe, Systems and Powerplants

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

  1. To increase the air velocity before combustion
  2. To drive the accessory gearbox through a bevel drive
  3. To cool the air prior to entering the combustion chamber
  4. To raise the static pressure of the air while reducing its velocity Correct answer.

Explanation

The diffuser converts the high-velocity, high-dynamic-pressure air leaving the compressor into a slower flow with higher static pressure, which is a prerequisite for stable combustion. It performs this conversion with little loss of total pressure, so the pressure rise is achieved by decelerating the airflow in a diverging passage.

Question 18Aircraft General Knowledge - Airframe, Systems and Powerplants

On a transport aircraft, the function of the bleed air precooler is to:

  1. Condense water vapour out of the bleed air for the pressurisation system
  2. Reduce the temperature of hydraulic fluid in the return line
  3. Reduce the temperature of engine bleed air before it enters the pneumatic distribution system Correct answer.
  4. Cool the engine oil before it returns to the oil tank

Explanation

Bleed air leaves the compressor at several hundred degrees Celsius and must be cooled to a level the ducts, valves and air-conditioning packs can tolerate. The precooler is an air-to-air heat exchanger, usually fed by fan air, that lowers this temperature before the air enters the manifold.

Question 19Aircraft General Knowledge - Airframe, Systems and Powerplants

What is the purpose of the torque link (scissors) fitted between the upper and lower parts of a main landing gear leg?

  1. It provides a mounting point for the brake torque plate
  2. It keeps the piston aligned with the cylinder and prevents rotation of the wheel assembly Correct answer.
  3. It carries the vertical landing loads into the airframe structure
  4. It retracts the gear by rotating the leg about its trunnion

Explanation

The oleo piston must be free to slide but must not rotate inside the cylinder, otherwise the wheel would change direction and steering or tracking would be lost. The torque link transmits torsional loads between the two halves while allowing the leg to extend and compress.

Question 20Aircraft General Knowledge - Airframe, Systems and Powerplants

In a pressurised aircraft, what is the role of the negative pressure relief valve?

  1. To regulate the cabin rate of climb during ascent
  2. To limit the maximum positive differential pressure
  3. To dump cabin pressure rapidly after touchdown
  4. To admit external air if cabin pressure falls below ambient pressure Correct answer.

Explanation

If cabin pressure ever drops below ambient, the fuselage would be loaded in the reverse direction, which the structure is not designed to withstand. The negative pressure relief valve opens inward to equalise the pressure and so protects the airframe.

Question 21Aircraft General Knowledge - Airframe, Systems and Powerplants

Which statement best describes the operation of a constant-speed propeller in flight?

  1. The pitch is adjusted so that blade angle changes absorb or release power as rpm tends to vary Correct answer.
  2. The blade angle is fixed and engine power is controlled solely by throttle
  3. The propeller rpm is held constant by varying the engine fuel flow only
  4. The blade angle is reduced as airspeed increases to keep rpm constant

Explanation

A constant-speed unit senses rpm and changes blade angle to keep the selected rpm. If power tends to raise rpm, the governor increases blade angle to absorb it; if rpm falls, blade angle is reduced to unload the engine.

Question 22Aircraft General Knowledge - Airframe, Systems and Powerplants

What is the principal structural function of a wing spar?

  1. To carry bending moments and shear loads from the wing to the fuselage Correct answer.
  2. To provide the aerodynamic shape of the leading edge
  3. To house the fuel tanks and prevent fuel sloshing
  4. To support the trailing edge flaps only

Explanation

The spar is the main beam of the wing and reacts the bending moments produced by lift, together with the shear forces. Spar booms carry tension and compression while the web carries shear, transmitting these loads into the fuselage attachments.

Question 23Aircraft General Knowledge - Airframe, Systems and Powerplants

In a multi-engine aircraft hydraulic system, what is the function of the accumulator?

  1. To automatically select the alternate hydraulic system
  2. To filter contamination from the hydraulic fluid
  3. To store hydraulic fluid under pressure and damp pressure surges Correct answer.
  4. To cool the hydraulic fluid returning to the reservoir

Explanation

The accumulator contains a trapped gas charge that is compressed as fluid enters, storing energy. This energy supplies pressure for transient high demands, damps pump pulsations and surges, and provides a limited reserve for emergency operation.

Question 24Aircraft General Knowledge - Airframe, Systems and Powerplants

An aircraft flies at a constant true airspeed at a constant altitude while the total weight decreases as fuel is burned. How does the required angle of attack change if the aircraft is to remain in steady level flight?

  1. It remains constant because true airspeed is constant
  2. It must increase progressively
  3. It must decrease progressively Correct answer.
  4. It increases only if the centre of gravity moves aft

Explanation

Lift must equal weight, and weight is falling, so the required lift coefficient decreases. Since lift coefficient falls with angle of attack in the normal operating range, the aircraft must fly at a smaller angle of attack to hold the same true airspeed.

Question 25Aircraft General Knowledge - Airframe, Systems and Powerplants

During a single-engine failure on a twin-engine aircraft with both engines mounted on the wings, why does the aircraft tend to yaw toward the failed engine?

  1. The failed engine windmills and produces reverse thrust
  2. The rudder becomes aerodynamically ineffective at low speed
  3. The operating engine produces a thrust moment about the centre of gravity that is unopposed Correct answer.
  4. The wing on the failed engine side generates more lift

Explanation

With one engine producing thrust offset laterally from the centre of gravity, a yawing moment is created toward the failed side. The pilot must apply rudder to produce an opposing moment, which is why asymmetric thrust control is critical after an engine failure.

Question 26Aircraft General Knowledge - Airframe, Systems and Powerplants

In a turbofan engine, what happens to the bypass ratio if the fan diameter is increased while the core mass flow is kept constant?

  1. The bypass ratio remains unchanged
  2. The bypass ratio becomes equal to the pressure ratio
  3. The bypass ratio decreases
  4. The bypass ratio increases Correct answer.

Explanation

Bypass ratio is the mass flow through the bypass duct divided by the mass flow through the core. Enlarging the fan while keeping core flow constant raises the bypass mass flow, so the ratio increases, which generally improves propulsive efficiency.

Question 27Aircraft General Knowledge - Airframe, Systems and Powerplants

A pitot-static system is blocked at the static port only, while the pitot head remains clear. During a climb, what will the airspeed indicator read?

  1. Zero airspeed
  2. The correct airspeed, because the pitot pressure is unaffected
  3. An airspeed lower than the actual airspeed
  4. An airspeed higher than the actual airspeed Correct answer.

Explanation

With the static port blocked, the trapped static pressure remains at the value at the moment of blockage. As the aircraft climbs, true ambient pressure falls below this trapped value, so the pressure difference measured by the instrument is too large and the indicated airspeed over-reads.

Question 28Aircraft General Knowledge - Airframe, Systems and Powerplants

Why is a swept wing used on high-speed jet transport aircraft?

  1. To increase the wing area for a given span
  2. To increase the critical Mach number by reducing the effective velocity component normal to the leading edge Correct answer.
  3. To improve low-speed handling characteristics on approach
  4. To reduce the structural weight of the wing box

Explanation

Sweeping the wing reduces the component of the free stream perpendicular to the leading edge, so the onset of local supersonic flow and shock-induced drag is delayed to a higher flight Mach number. This raises the critical Mach number and allows efficient cruising near the speed of sound.

Question 29Aircraft General Knowledge - Airframe, Systems and Powerplants

In a fuel system, what is the purpose of the crossfeed valve on a twin-engine aircraft?

  1. To vent excess fuel overboard during refuelling
  2. To shut off fuel to both engines in an emergency
  3. To allow either engine to be supplied from either wing tank Correct answer.
  4. To transfer fuel automatically to balance the aircraft

Explanation

The crossfeed valve connects the left and right engine feed lines so that fuel from one side can supply both engines or either engine. This is used to correct lateral imbalance and to keep both engines running after a single tank or pump failure.

Question 30Aircraft General Knowledge - Airframe, Systems and Powerplants

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

  1. To filter particles from the fluid before it reaches the actuator
  2. To limit the maximum system pressure by bypassing the pump
  3. To melt and release pressure if the fluid temperature exceeds a limit
  4. To isolate a leaking downstream line by shutting off flow once a set volume has passed Correct answer.

Explanation

A hydraulic fuse senses the volume of fluid passing through it and closes when that volume exceeds a preset value, indicating a downstream leak. This confines fluid loss to a small quantity and preserves pressure for the rest of the system.

Question 31Aircraft General Knowledge - Airframe, Systems and Powerplants

In an air-cycle air-conditioning machine, what is the effect of the primary heat exchanger?

  1. It mixes recirculated cabin air with fresh bleed air
  2. It cools the air after the compressor but before the turbine
  3. It removes water from the air after the turbine
  4. It cools the hot engine bleed air before it enters the compressor Correct answer.

Explanation

The air-cycle pack takes hot bleed air and first passes it through the primary heat exchanger, which is cooled by ram or fan air, before it is compressed in the pack compressor. Cooling before compression reduces the compressor work and the final delivery temperature.

Question 32Aircraft General Knowledge - Airframe, Systems and Powerplants

What is the purpose of the freewheel unit in a starter-generator drive on a gas turbine engine?

  1. To allow manual rotation of the engine during maintenance
  2. To disconnect the generator from the busbar during a fault
  3. To prevent the starter from being driven by the engine once it has started Correct answer.
  4. To limit the starter torque to protect the gearbox

Explanation

Once the engine accelerates above starter speed, the engine would otherwise drive the starter, which is not designed to be spun at high speed. The freewheel, or sprag clutch, transmits torque in one direction only and overruns in the other, protecting the starter.

Question 33Aircraft General Knowledge - Airframe, Systems and Powerplants

In a Machmeter, what happens to the indicated Mach number if the pitot head becomes blocked while the static port remains clear during a descent at constant true airspeed?

  1. It oscillates around the true value
  2. It decreases toward zero Correct answer.
  3. It increases above the true Mach number
  4. It remains constant at the value at the time of blockage

Explanation

A blocked pitot head traps the pitot pressure at the value when the blockage occurred, while the static pressure continues to rise during the descent. The difference between pitot and static pressure therefore falls, and the indicated Mach number falls accordingly.

Question 34Aircraft General Knowledge - Airframe, Systems and Powerplants

What is the significance of the term Vmcg in multi-engine performance?

  1. The minimum speed for clean configuration flight
  2. The maximum speed at which the gear may be retracted
  3. The minimum control speed on the ground with the critical engine inoperative Correct answer.
  4. The speed for best single-engine climb gradient

Explanation

Vmcg is the minimum speed on the ground at which directional control can be maintained with the critical engine failed and the other at take-off power, using only aerodynamic controls. Below this speed, rudder authority is insufficient to counter the asymmetric thrust.

Question 35Aircraft General Knowledge - Airframe, Systems and Powerplants

An aircraft is in a steady level turn at 60 degrees of bank. If the stall speed in level flight is 100 knots, what is the approximate stall speed in the turn?

  1. 173 knots
  2. 200 knots
  3. 141 knots Correct answer.
  4. 120 knots

Explanation

The load factor in a level turn is 1 divided by the cosine of the bank angle, which at 60 degrees is 2. Stall speed rises with the square root of the load factor, so the new stall speed is 100 times the square root of 2, about 141 knots.

Question 36Aircraft General Knowledge - Airframe, Systems and Powerplants

What is the primary reason that turbine engine compressor blades are usually made with a twist along their span?

  1. To reduce the centrifugal stress at the blade root
  2. To maintain an appropriate angle of attack at each radius as tangential velocity varies with radius Correct answer.
  3. To allow the blade to be reversed for thrust reversal
  4. To improve the cooling airflow through internal passages

Explanation

The tangential velocity of the air and blade increases with radius, so a constant blade angle would give an unsuitable incidence at the tip or root. Twisting the blade maintains an efficient angle of attack along the span and reduces losses.

Question 37Aircraft General Knowledge - Airframe, Systems and Powerplants

In a fuel-oil heat exchanger, what is the main advantage of using fuel as the cooling medium for engine oil?

  1. It keeps the fuel at a constant temperature regardless of altitude
  2. It removes the need for a fuel filter
  3. It heats the fuel for better combustion while cooling the oil, recovering energy otherwise lost Correct answer.
  4. It eliminates the need for an oil pump

Explanation

Fuel is a convenient heat sink because it is carried on board and ultimately burned. Cooling the oil raises the fuel temperature, which improves atomisation and combustion and recovers heat that would otherwise be rejected overboard.

Question 38Aircraft General Knowledge - Airframe, Systems and Powerplants

During a rejected take-off, why can the brakes reach their highest temperatures after the aircraft has come to a stop?

  1. The anti-skid system releases pressure and generates additional heat
  2. With little or no airflow over the brake pack, heat conduction to the wheel and tyre continues without effective convective cooling Correct answer.
  3. The brake discs expand and increase friction after stopping
  4. Hydraulic pressure continues to be applied by the parking brake and adds energy

Explanation

The kinetic energy is converted to heat during the stop, but much of it is stored in the brake pack and diffuses into the wheel and tyre afterwards. Once the aircraft is stationary, wheel cooling airflow is minimal, so the peak temperatures are often reached some minutes after the stop.

Question 39Aircraft General Knowledge - Airframe, Systems and Powerplants

What is the effect of a forward movement of the centre of gravity on the trim drag and on the stability of a conventional aircraft?

  1. Trim drag decreases and static stability increases
  2. Trim drag decreases and static stability decreases
  3. Trim drag increases and static stability increases Correct answer.
  4. Trim drag increases and static stability decreases

Explanation

Moving the centre of gravity forward increases the distance from the centre of gravity to the tail, so a larger download and hence more trim drag is needed to balance the aircraft. The larger moment arm of the tail relative to the centre of gravity also increases longitudinal static stability.

Question 40Aircraft General Knowledge - Airframe, Systems and Powerplants

In a high-bypass turbofan, why does a fan blade tip clearance increase in flight compared with the cold static condition?

  1. The casing expands more than the rotor because it is hotter
  2. The fan rotates more slowly in flight, allowing the blades to move outward
  3. The blade material contracts at low ambient temperature
  4. Centrifugal growth of the disc and blades exceeds the thermal growth of the casing Correct answer.

Explanation

At operating speed the fan disc and blades stretch radially under centrifugal load, and this mechanical growth is larger than the thermal expansion of the surrounding casing. The result is that tip clearance is generally larger at high rotational speed than when cold and static, which is why active clearance control is used on some engines.

Question 41Flight Performance and Planning

In the take-off distance chart, increasing the aerodrome pressure altitude while all other factors remain constant will cause the take-off ground roll to:

  1. Remain constant, because the chart is based on indicated airspeed only
  2. Decrease, because the engine produces more power in thinner air
  3. Increase, because the lower air density reduces thrust and lift for a given IAS Correct answer.
  4. Decrease, because the higher true airspeed improves tyre friction

Explanation

Higher pressure altitude means lower air density, so for the same indicated airspeed the true airspeed and ground speed are higher, and both propeller thrust and lift decrease. The aircraft therefore accelerates more slowly and needs a longer ground roll. The chart is entered with pressure altitude precisely because density strongly affects take-off performance.

Question 42Flight Performance and Planning

The landing distance required is normally quoted as the distance from a 50 ft screen height to a full stop. This distance is:

  1. The landing distance required multiplied by 1.43 Correct answer.
  2. The actual landing distance multiplied by 1.67
  3. The landing distance available multiplied by 1.15
  4. The accelerate-stop distance divided by 1.92

Explanation

Certification rules require the landing distance required to be the demonstrated landing distance from 50 ft multiplied by a factor of 1.43 for commercial transport aeroplanes. This provides a safety margin for pilot technique and conditions. The factor applies to the demonstrated (unfactored) distance, not to the available runway.

Question 43Flight Performance and Planning

An aeroplane is to be dispatched with a take-off mass limited by the climb-limited take-off mass. If the outside air temperature at the departure aerodrome increases, the climb-limited take-off mass will generally:

  1. Increase, because the engine burns fuel faster
  2. Decrease, because reduced density lowers excess thrust available for climb Correct answer.
  3. Remain unchanged, because climb mass depends only on pressure altitude
  4. Increase, because the wing generates more lift

Explanation

Warmer air reduces density, which lowers the thrust available and slightly reduces lift for a given IAS. The excess thrust available for climbing is therefore reduced, so the maximum mass that still satisfies the required climb gradient decreases. Climb-limited mass charts are therefore entered with temperature as well as pressure altitude.

Question 44Flight Performance and Planning

On a load sheet, the centre of gravity is expressed as a percentage of the mean aerodynamic chord. If the CG is at 18% MAC and the aft limit is 35% MAC, the aircraft is:

  1. Outside limits, aft of the aft limit
  2. Outside limits, forward of the forward limit
  3. Within limits but close to the aft limit
  4. Within limits and close to the forward limit Correct answer.

Explanation

A CG at 18% MAC lies between the forward and aft limits and is numerically closer to the forward limit than to 35% MAC. The aircraft is therefore within limits but with little margin to the forward limit. This matters because forward CG increases stick force and reduces elevator authority.

Question 45Flight Performance and Planning

For a given mass, the stalling speed in a level 60-degree banked turn compared with level flight is approximately:

  1. 1.41 times higher Correct answer.
  2. 2.00 times higher
  3. The same, because stall depends only on angle of attack
  4. 1.20 times higher

Explanation

In a 60-degree bank the load factor is 1/cos 60 = 2. Stall speed varies with the square root of the load factor, so the stall speed increases by the square root of 2, about 1.41. The stall angle of attack is unchanged, but the higher speed is required to produce the extra lift.

Question 46Flight Performance and Planning

During a take-off, the decision speed V1 is defined as the speed:

  1. At or above which a failure before V1 allows a continued take-off
  2. At which the nosewheel is raised for rotation
  3. At which the aircraft becomes airborne
  4. At or above which a failure allows the take-off to be abandoned and the aircraft stopped on the runway Correct answer.

Explanation

V1 is the maximum speed at which a rejected take-off can be initiated and the aeroplane stopped within the accelerate-stop distance available. It is also the minimum speed at which, following an engine failure, the take-off can be safely continued. V1 is therefore the decision speed linking the two cases.

Question 47Flight Performance and Planning

The maximum crosswind component for a given aeroplane is 20 kt. If the wind is reported as 300 degrees at 25 kt and the runway in use is 330 degrees, the crosswind component is approximately:

  1. 12.5 kt Correct answer.
  2. 5.0 kt
  3. 25.0 kt
  4. 21.7 kt

Explanation

The angle between wind and runway is 30 degrees. The crosswind component equals wind speed multiplied by the sine of that angle, so 25 times sin 30 = 12.5 kt. This is below the 20 kt limit, so the take-off is permitted from a crosswind standpoint.

Question 48Flight Performance and Planning

The maximum take-off mass of an aeroplane is often limited by the requirement to clear obstacles in the take-off flight path. This limitation is described as the:

  1. Tyre-speed-limited mass
  2. Field-length-limited mass
  3. Brake-energy-limited mass
  4. Obstacle-limited mass Correct answer.

Explanation

When the governing restriction is the ability to clear obstacles after lift-off, the resulting limit is the obstacle-limited take-off mass. It is found by comparing the net take-off flight path with the obstacle profile. Field length, brakes and tyres are separate limiting cases.

Question 49Flight Performance and Planning

An aeroplane burns fuel during cruise, moving its centre of gravity. If the CG moves aft within limits, the cruise fuel consumption typically:

  1. Increases because the wing must produce more lift
  2. Remains exactly the same because mass is unchanged
  3. Decreases because a smaller tailplane downforce reduces induced drag Correct answer.
  4. Increases because the tailplane must produce more downforce

Explanation

An aft CG reduces the download required from the tailplane to balance the wing pitching moment, so the total lift and the associated induced drag are lower. Consequently, specific range improves and fuel consumption for a given cruise decreases. This is why some operators manage fuel to keep the CG near the aft limit.

Question 50Flight Performance and Planning

The pressure altitude of an aerodrome is 2000 ft and the QNH is 1013 hPa. The aerodrome elevation is closest to:

  1. 1013 ft
  2. 0 ft
  3. 4000 ft
  4. 2000 ft Correct answer.

Explanation

Pressure altitude is the altitude indicated when the altimeter subscale is set to 1013 hPa. When the actual QNH equals 1013 hPa, the pressure altitude equals the true elevation of the aerodrome. The elevation is therefore 2000 ft.