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GCAA Ghana CPL Theory Exam study materials
GCAA Ghana CPL Theory Exam study resources

GCAA Ghana CPL Theory Exam practice questions

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Question 1Air Law

Under the Ghana Civil Aviation (Aircraft Registration and Marking) Rules, which nationality mark must appear on every Ghanaian-registered aircraft?

  1. 9G Correct answer.
  2. GHA
  3. 9G-
  4. GH

Explanation

Ghana is allocated the nationality mark 9G by ICAO, and this prefix precedes the registration mark in the common mark carried on the fuselage or vertical tail. The mark must be painted so that it is clearly visible and contrasts with the background.

Question 2Air Law

An applicant for a Ghanaian Commercial Pilot Licence (Aeroplane) must hold at least which prior licence or qualification before the CPL skill test?

  1. A valid Flight Radio Telephony Licence only
  2. A valid Student Pilot Licence only
  3. A valid Airline Transport Pilot Licence
  4. A valid Private Pilot Licence (Aeroplane) Correct answer.

Explanation

The CPL is a professional licence built on the private licence; the candidate must already hold a valid PPL(A) with the required experience and ground subjects completed. A student licence or radio licence alone does not meet the prerequisite.

Question 3Air Law

Which document must be carried on board an aircraft operating an international flight under the Convention on International Civil Aviation and be produced for inspection on landing?

  1. The maintenance schedule of the operator
  2. The company operations manual
  3. The certificate of registration of the aircraft Correct answer.
  4. The pilot's personal logbook

Explanation

Article 29 of the Chicago Convention lists the certificate of registration among the documents that must be carried on board. It evidences the aircraft's nationality and must be produced for inspection.

Question 4Air Law

In the Ghana Civil Aviation (Rules of the Air) provisions, the standard cruising level for flights above 8,850 feet on tracks from 000 to 179 degrees magnetic is which of the following?

  1. Odd thousands of feet Correct answer.
  2. Odd thousands plus 500 feet
  3. Even thousands of feet
  4. Even thousands plus 500 feet

Explanation

Under the semicircular rule, tracks from 000 to 179 degrees magnetic use odd thousands of feet, while tracks from 180 to 359 degrees use even thousands. The plus-500 levels apply to IFR flights in some airspace tables but the base rule for magnetic tracks 000-179 is odd thousands.

Question 5Air Law

Which body is responsible for the investigation of accidents and serious incidents involving civil aircraft in Ghana?

  1. The Ghana Airports Company Limited
  2. The Ghana Civil Aviation Authority
  3. The Aircraft Accident Investigation Bureau Correct answer.
  4. The Ghana Meteorological Agency

Explanation

Accident investigation is separated from the regulator to preserve independence; Ghana established a dedicated accident investigation bureau for this purpose. The GCAA regulates safety and licensing but does not conduct the independent investigation.

Question 6Air Law

Under the Ghana Civil Aviation (Air Navigation) Regulations, an aircraft in the vicinity of an aerodrome must give way to which of the following?

  1. Aircraft on final approach to land Correct answer.
  2. Aircraft taxiing on the apron
  3. Aircraft being refuelled
  4. Aircraft parked on the ramp

Explanation

Aircraft in flight, and aircraft on the ground, must give way to aircraft landing or on final approach to land. This protects the landing aircraft, which has the least ability to manoeuvre.

Question 7Air Law

A Ghanaian CPL holder's Class 1 medical certificate has expired, but the pilot's licence itself remains valid. What is the pilot's status for exercising the privileges of the licence?

  1. The pilot may continue flying for 30 days after expiry
  2. The pilot may fly if accompanied by a current instructor
  3. The pilot may fly only as a co-pilot
  4. The pilot may not exercise the licence privileges until the medical is renewed Correct answer.

Explanation

The medical certificate is a condition of validity for the licence; when it lapses the pilot cannot exercise the licence privileges until it is renewed. There is no automatic grace period for a Class 1 medical.

Question 8Air Law

A Ghanaian-registered aircraft is wet-leased to a foreign operator for a period of six months. Which authority remains responsible for the continuing airworthiness of the aircraft?

  1. The authority of the manufacturer's state
  2. The Ghana Civil Aviation Authority Correct answer.
  3. The authority of the lessee's state
  4. The authority of the state of the crew's nationality

Explanation

The state of registry retains responsibility for continuing airworthiness unless a transfer of functions has been formally agreed under Article 83 bis. A wet lease does not by itself transfer that responsibility.

Question 9Air Law

A pilot on a Ghanaian CPL is planning a flight and finds that the destination aerodrome forecast indicates the weather will be below the operator's minima on arrival. What is the correct action under the operator's fuel and alternate planning rules?

  1. Plan to divert to the departure aerodrome regardless of distance
  2. Plan to land at the destination using the pilot's discretion
  3. Plan and carry fuel to a suitable alternate aerodrome Correct answer.
  4. Plan to hold until the weather improves

Explanation

When the destination forecast is below the required planning minima, the flight must be planned with a suitable alternate and the fuel to reach it. Holding or relying on pilot discretion does not satisfy the planning requirement.

Question 10Air Law

During a night flight, a pilot observes an aircraft approaching head-on with a steady red light on the right and a steady green light on the left. What does this indicate?

  1. The aircraft is crossing from right to left
  2. The aircraft is moving away from the observer
  3. The aircraft is approaching head-on or nearly so Correct answer.
  4. The aircraft is crossing from left to right

Explanation

Navigation lights are red on the left wingtip and green on the right wingtip; seeing both simultaneously means the other aircraft is approaching head-on or nearly so. The pilot should alter course to the right to pass well clear.

Question 11Air Law

A pilot holds a Ghanaian CPL and wishes to add a multi-engine piston class rating. Which requirement must be satisfied before the rating can be issued?

  1. A minimum of 1,000 hours total flight time
  2. A recommendation from the aircraft manufacturer
  3. An ATPL ground examination pass
  4. Completion of the approved training and a skill test with an authorised examiner Correct answer.

Explanation

Class and type ratings are issued after approved training and a skill test with an authorised examiner. Total hours and manufacturer recommendations are not the governing requirement for a class rating.

Question 12Air Law

An aircraft is involved in an incident in which a passenger suffers a serious injury during boarding at Kotoka International Airport. Which classification applies under the accident investigation rules?

  1. An incident only, because the aircraft was not in flight
  2. A serious incident, because boarding was in progress
  3. An accident, because a serious injury occurred in connection with the aircraft's operation Correct answer.
  4. No reportable occurrence, because no aircraft damage occurred

Explanation

An occurrence in which a person suffers serious injury in connection with the operation of an aircraft is an accident, whether or not the aircraft was in flight. Boarding is part of the operation, so the event is reportable as an accident.

Question 13Air Law

An operator based in Accra wishes to conduct non-scheduled international charter flights using a Ghanaian-registered aircraft. Which authorisation is required in addition to the air operator certificate?

  1. A separate private pilot licence for each crew member
  2. A new certificate of registration for each flight
  3. An operating authorisation or permit for the specific flights Correct answer.
  4. A foreign air operator certificate

Explanation

Non-scheduled international operations require an operating authorisation or permit in addition to the AOC, consistent with the requirements for commercial air transport. The AOC establishes competence, while the permit authorises the specific operation.

Question 14Air Law

Under the Ghana Civil Aviation (Rules of the Air) Regulations, what is the minimum flight visibility required for a VFR flight at or below 900 feet AMSL in controlled airspace?

  1. 3,000 metres
  2. 5,000 metres Correct answer.
  3. 1,500 metres
  4. 8,000 metres

Explanation

The VFR meteorological minima table sets a flight visibility of 5,000 metres at or below 900 feet AMSL in controlled airspace. Lower values apply only in specific reduced-visibility cases such as special VFR clearances.

Question 15Air Law

A pilot is cleared to enter the Accra control zone and is instructed to 'report on the ground'. What does this instruction require?

  1. Advise ATC when the aircraft is on the apron
  2. Advise ATC when the aircraft is on final approach
  3. Advise ATC when the aircraft is ready for departure
  4. Advise ATC when the aircraft has landed Correct answer.

Explanation

The phrase 'report on the ground' is an instruction to notify ATC once the aircraft has landed and is on the ground. It is used so the controller knows the flight has safely completed and the runway is free.

Question 16Air Law

A Ghanaian CPL holder is offered a flight in a foreign-registered aircraft in a state that requires validation of the licence. What is the correct course of action?

  1. Obtain the required validation from that state before acting as pilot in command Correct answer.
  2. Ask the foreign operator to issue a temporary licence
  3. Fly only as a passenger and log the time as pilot in command
  4. Fly using the Ghanaian licence alone, since ICAO recognises all licences

Explanation

A licence issued by one state does not automatically authorise flight in another state's aircraft; the pilot must obtain whatever validation that state requires. ICAO recognition applies to the licence's standing, not to automatic permission to fly foreign-registered aircraft.

Question 17Air Law

An aircraft registered in Ghana is sold to a buyer in another state. Which action must the seller take to address the Ghanaian registration?

  1. Transfer the certificate of registration directly to the buyer
  2. Notify the Ghana Civil Aviation Authority so the registration is cancelled and a certificate of deregistration issued Correct answer.
  3. Continue operating the aircraft under the Ghanaian registration indefinitely
  4. Retain the Ghanaian registration until the buyer registers abroad

Explanation

When an aircraft leaves the Ghanaian register, the seller must notify the authority so that the registration is cancelled and a certificate of deregistration is issued. This document allows the new state of registry to register the aircraft.

Question 18Air Law

An air traffic controller issues a clearance that requires a pilot to deviate from the notified standard departure procedure. How should the pilot respond?

  1. Refuse the clearance because published procedures cannot be amended
  2. Request a new clearance only if weather permits
  3. Accept the clearance if able, since an ATC clearance takes precedence over the published procedure Correct answer.
  4. Follow the published procedure and ignore the clearance

Explanation

An ATC clearance overrides a published procedure when the two conflict, provided the pilot can comply and accepts responsibility for terrain and obstacle clearance where the clearance is ambiguous. The pilot should read back and clarify any doubt before proceeding.

Question 19Air Law

A serious incident occurs during a commercial flight in Ghanaian airspace. Which statement best describes the operator's obligation to the investigating authority?

  1. The operator may delay notification until the flight has been completed and the aircraft cleaned
  2. The operator must notify the investigating authority promptly and preserve evidence, including flight recorders Correct answer.
  3. The operator must notify the press before notifying the authority
  4. The operator must notify the manufacturer first and the authority second

Explanation

The operator is required to notify the investigating authority without delay and to preserve evidence, including flight data and cockpit voice recorders, so the investigation is not compromised. Cleaning or moving the aircraft before authorisation can destroy evidence.

Question 20Air Law

A Ghanaian operator plans a flight that will enter the airspace of a neighbouring state. What is the key regulatory consideration for the flight crew regarding that state's rules?

  1. Only ICAO Annexes apply, since they override national rules
  2. The rules of the aircraft manufacturer's state apply
  3. The rules of the state whose airspace is entered apply while the aircraft is in that airspace Correct answer.
  4. Only Ghanaian rules apply throughout the flight

Explanation

Each state applies its own rules to aircraft within its territory, so the crew must comply with the rules of the state whose airspace is entered while in that airspace. Ghanaian rules continue to apply to the aircraft's general operation and airworthiness.

Question 21Aircraft General Knowledge and Principles of Flight

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

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

Explanation

The intake stroke draws the fuel-air mixture into the cylinder while the intake valve is open and the piston descends, increasing cylinder volume. The other three strokes involve closed or differently timed valves and different piston directions.

Question 22Aircraft General Knowledge and Principles of Flight

The purpose of the carburettor venturi in a piston engine induction system is to:

  1. Regulate the oil pressure supplied to the bearings
  2. Cool the fuel before it reaches the float chamber
  3. Increase air velocity and lower pressure so fuel is drawn into the airstream Correct answer.
  4. Filter dust particles out of the incoming air

Explanation

As air passes through the narrowed venturi its velocity rises and static pressure falls, creating the low pressure that draws fuel from the discharge nozzle and atomises it. This is a direct application of Bernoulli's principle within the induction system.

Question 23Aircraft General Knowledge and Principles of Flight

Which of the following is the primary function of the magneto in a light aircraft piston engine?

  1. To step down battery voltage for the avionics bus
  2. To supply high-tension electrical energy to the spark plugs independently of the aircraft battery Correct answer.
  3. To charge the aircraft battery during flight
  4. To convert alternating current from the alternator into direct current

Explanation

A magneto is a self-contained engine-driven generator that produces its own high voltage for ignition, so the engine keeps running even if the aircraft electrical system fails. This independence is why dual magnetos are used for redundancy.

Question 24Aircraft General Knowledge and Principles of Flight

The main advantage of a constant-speed propeller over a fixed-pitch propeller is that it:

  1. Removes the requirement for a propeller governor
  2. Maintains an efficient blade angle across a wide range of airspeeds and engine powers Correct answer.
  3. Allows the engine to run without a reduction gear at all times
  4. Eliminates the need for engine oil to lubricate the hub

Explanation

A constant-speed unit changes blade angle to keep the selected RPM, so the propeller stays near its most efficient angle of attack in climb and cruise. A fixed-pitch propeller can only be optimised for one condition.

Question 25Aircraft General Knowledge and Principles of Flight

In straight-and-level flight at constant airspeed, lift is:

  1. Less than weight
  2. Equal to thrust
  3. Greater than weight
  4. Equal to weight Correct answer.

Explanation

In unaccelerated level flight the vertical forces must balance, so total lift equals total weight. Thrust balances drag in the horizontal axis, which is a separate balance.

Question 26Aircraft General Knowledge and Principles of Flight

The angle of attack of a wing is defined as the angle between the:

  1. Mean camber line and the horizontal
  2. Wing upper surface and the relative airflow
  3. Chord line and the longitudinal axis
  4. Chord line and the relative airflow Correct answer.

Explanation

Angle of attack is measured between the wing chord line and the direction of the relative airflow. It is not the same as pitch attitude, which is referenced to the horizon or aircraft axes.

Question 27Aircraft General Knowledge and Principles of Flight

Which control surface produces the primary rolling moment about the longitudinal axis?

  1. The rudder
  2. The flaps
  3. The elevators
  4. The ailerons Correct answer.

Explanation

Ailerons move differentially to increase lift on one wing and decrease it on the other, generating roll about the longitudinal axis. Elevators control pitch and the rudder controls yaw.

Question 28Aircraft General Knowledge and Principles of Flight

Compared with straight-and-level flight, the stalling angle of attack of a wing is:

  1. Higher at higher altitude
  2. The same regardless of weight, bank angle or airspeed Correct answer.
  3. Lower when the aircraft is banked
  4. Higher when the aircraft is heavier

Explanation

The critical angle of attack at which airflow separates is a fixed aerodynamic property of the wing section. Weight, bank and altitude change the speed at which that angle is reached, not the angle itself.

Question 29Aircraft General Knowledge and Principles of Flight

An aircraft is in a steady level turn at 60 degrees of bank. The load factor is approximately:

  1. 3.0
  2. 1.0
  3. 2.0 Correct answer.
  4. 1.4

Explanation

Load factor in a level turn equals one divided by the cosine of the bank angle. The cosine of 60 degrees is 0.5, so the load factor is 1/0.5, which is 2.

Question 30Aircraft General Knowledge and Principles of Flight

If an aircraft's true airspeed doubles while all other factors remain constant, the induced drag will:

  1. Reduce to one quarter of its original value Correct answer.
  2. Double
  3. Reduce to one half of its original value
  4. Remain unchanged

Explanation

Induced drag is inversely proportional to the square of airspeed at a given weight. Doubling airspeed therefore reduces induced drag by a factor of four, although parasite drag rises sharply.

Question 31Aircraft General Knowledge and Principles of Flight

Detonation in a piston engine is best described as:

  1. Combustion that occurs only after the exhaust valve opens
  2. Normal progressive flame-front combustion spreading from the spark plug
  3. Explosive, uncontrolled combustion of the fuel-air charge after ignition Correct answer.
  4. Pre-ignition caused by a glowing spark plug electrode

Explanation

Detonation occurs when the unburnt end gas ignites spontaneously and burns explosively rather than by a smooth flame front, producing a knocking sound and high cylinder pressures. It differs from pre-ignition, which is ignition before the spark.

Question 32Aircraft General Knowledge and Principles of Flight

An engine's fuel-air mixture is leaned during a climb in a normally aspirated aircraft. The main reason is to:

  1. Increase the octane rating of the fuel
  2. Reduce the cylinder head temperature below the minimum
  3. Compensate for decreasing air density so the mixture does not become excessively rich Correct answer.
  4. Prevent the magneto from overheating

Explanation

As altitude increases, air density falls and the carburettor delivers less air for the same fuel flow, so the mixture becomes richer. Leaning restores the correct fuel-air ratio and improves power and economy.

Question 33Aircraft General Knowledge and Principles of Flight

Carburettor icing is most likely to occur when the outside air temperature is:

  1. Below -30 degrees Celsius in clear air
  2. Between about -10 and +10 degrees Celsius with high relative humidity Correct answer.
  3. Exactly at 0 degrees Celsius with no moisture present
  4. Above 30 degrees Celsius with very dry air

Explanation

Vaporisation of fuel and the pressure drop in the venturi cool the mixture, so icing can form in moderately cool, moist air even when outside temperature is well above freezing. The danger range is roughly -10 to +10 degrees Celsius with high humidity.

Question 34Aircraft General Knowledge and Principles of Flight

The critical engine on a conventional twin-engine aircraft with both propellers turning clockwise when viewed from the cockpit is:

  1. The engine with the higher oil temperature
  2. The left engine Correct answer.
  3. The right engine
  4. Neither engine, because they are symmetrical

Explanation

With both propellers turning clockwise, the left engine's critical-engine effects are more pronounced because its P-factor and asymmetric blade effect act further from the aircraft centreline. Loss of the left engine therefore demands the greater rudder force and produces the larger yaw.

Question 35Aircraft General Knowledge and Principles of Flight

During a steady climb at a constant airspeed, the component of weight acting along the flight path:

  1. Equals the lift produced by the wing
  2. Acts forward and assists thrust
  3. Is zero because weight acts vertically
  4. Acts rearward and must be overcome by thrust in addition to drag Correct answer.

Explanation

In a climb the weight vector has a rearward component along the flight path, so thrust must balance both drag and this weight component. Lift is correspondingly reduced because it balances only the perpendicular component of weight.

Question 36Aircraft General Knowledge and Principles of Flight

Aircraft stability about the lateral axis is provided mainly by:

  1. The vertical fin and rudder
  2. The wing sweep angle
  3. The horizontal stabiliser and elevator assembly Correct answer.
  4. The dihedral angle of the wings

Explanation

Longitudinal (pitch) stability about the lateral axis depends primarily on the tailplane, whose surface area and moment arm damp pitch disturbances. The fin provides directional stability and dihedral provides lateral stability.

Question 37Aircraft General Knowledge and Principles of Flight

An aircraft with a forward centre of gravity compared with one at the aft limit will generally have:

  1. No change in take-off performance
  2. A longer take-off run and higher stalling speed Correct answer.
  3. A shorter take-off run and lower stalling speed
  4. Improved pitch stability but a higher cruise speed

Explanation

A forward centre of gravity increases the tail-down moment that the tailplane must counter, raising the required lift and hence the stalling speed, while also lengthening the take-off run. The aft limit gives better performance but reduced pitch stability.

Question 38Aircraft General Knowledge and Principles of Flight

The purpose of a spring tab on a large aircraft control surface is to:

  1. Reduce the pilot's control forces at high airspeeds by assisting surface deflection Correct answer.
  2. Trim the aircraft about the normal axis
  3. Lock the control surface when the aircraft is parked
  4. Provide artificial feel proportional to airspeed

Explanation

A spring tab deflects when control forces rise, aerodynamically helping to move the main surface so pilot effort stays manageable at high speed. It is one of several aerodynamic balance devices used on large aircraft.

Question 39Aircraft General Knowledge and Principles of Flight

Which statement correctly describes the relationship between true airspeed, indicated airspeed and altitude?

  1. True airspeed always equals indicated airspeed above 10 000 feet
  2. True airspeed decreases as air density decreases
  3. For a given indicated airspeed, true airspeed increases as altitude increases Correct answer.
  4. Indicated airspeed increases with altitude for a constant true airspeed

Explanation

Indicated airspeed reflects dynamic pressure, which depends on air density. As altitude rises and density falls, a given true airspeed produces less dynamic pressure, so for a fixed indicated airspeed the true airspeed must be higher.

Question 40Aircraft General Knowledge and Principles of Flight

A wing at a high angle of attack approaches the stall. Which change would most effectively delay the onset of the stall?

  1. Increasing the aircraft weight
  2. Deploying leading-edge slats Correct answer.
  3. Retracting the flaps
  4. Reducing the airspeed

Explanation

Leading-edge slats re-energise the airflow over the upper surface and allow the wing to reach a higher angle of attack before separation, increasing the critical angle. Weight and reduced airspeed do not change the critical angle.

Question 41Aircraft General Knowledge and Principles of Flight

An aircraft is descending at a constant rate with constant airspeed in a steady glide. If the pilot raises the nose slightly without changing power, the aircraft will initially:

  1. Decelerate because a component of weight now opposes thrust Correct answer.
  2. Maintain the same airspeed because lift equals weight
  3. Climb because lift exceeds weight
  4. Accelerate because drag is reduced

Explanation

In a glide, thrust is zero and the forward weight component balances drag. Raising the nose reduces that forward component, so drag exceeds the propelling force and the aircraft decelerates until a new equilibrium is reached.

Question 42Aircraft General Knowledge and Principles of Flight

A turbine engine's compressor is fitted with variable inlet guide vanes primarily to:

  1. Filter foreign objects before they reach the compressor
  2. Optimise the airflow angle onto the first-stage rotor blades across different engine speeds Correct answer.
  3. Increase the fuel flow to the combustion chamber
  4. Cool the compressor casing during high-power operation

Explanation

Variable inlet guide vanes change the direction of incoming air so that the first-stage rotor blades see an appropriate angle of attack at varying RPM, which improves compressor efficiency and stall margin. They are an aerodynamic scheduling device, not a filter or fuel control.

Question 43Aircraft General Knowledge and Principles of Flight

In a jet engine, the primary purpose of the exhaust nozzle is to:

  1. Drive the accessory gearbox
  2. Accelerate the exhaust gases to produce thrust Correct answer.
  3. Reduce the temperature of the exhaust gases
  4. Compress the incoming air before combustion

Explanation

The nozzle converts the remaining pressure and thermal energy of the exhaust into velocity, and the change in momentum of the accelerated gases produces thrust. Compression and accessory drive occur earlier in the engine.

Question 44Aircraft General Knowledge and Principles of Flight

An aircraft is flying at a constant true airspeed in a level turn. If the bank angle is increased from 30 to 60 degrees while maintaining level flight, the stalling speed will:

  1. Increase by a factor of approximately 1.41 Correct answer.
  2. Remain unchanged
  3. Decrease by a factor of approximately 1.41
  4. Increase by a factor of approximately 2.0

Explanation

Stalling speed varies with the square root of load factor. At 30 degrees the load factor is about 1.15 and at 60 degrees it is 2.0, so the stalling speed rises by the square root of 2/1.15, approximately 1.41.

Question 45Aircraft General Knowledge and Principles of Flight

A pilot notices that the turn coordinator shows a standard-rate turn but the ball is displaced to the outside of the turn. The correct interpretation is that the aircraft is:

  1. Slipping and requires rudder input toward the inside of the turn Correct answer.
  2. Stalled and requires immediate pitch reduction
  3. Skidding and requires rudder input toward the outside of the turn
  4. In perfect balance and requires no rudder input

Explanation

When the ball sits on the outside of the turn, the rate of yaw is insufficient for the bank, so the aircraft is slipping inward. Corrective rudder is applied toward the inside of the turn, that is, toward the ball.

Question 46Aircraft General Knowledge and Principles of Flight

In a four-stroke piston engine, the sequence of events in one complete cycle of a cylinder is:

  1. Induction, compression, exhaust, power
  2. Compression, induction, power, exhaust
  3. Induction, compression, power, exhaust Correct answer.
  4. Induction, power, compression, exhaust

Explanation

A four-stroke cycle requires two complete revolutions of the crankshaft, giving four distinct strokes: the piston descends drawing in the fuel-air charge (induction), rises compressing it (compression), is driven down by combustion (power), and rises again expelling the burnt gases (exhaust). The order is fixed by the camshaft timing, and the power stroke is the only one that delivers work to the crankshaft.

Question 47Aircraft General Knowledge and Principles of Flight

The main function of the magneto in a piston aero engine is to:

  1. Supply a high-tension voltage to the spark plugs at the correct moment Correct answer.
  2. Provide the low-voltage current used by the starter motor
  3. Regulate the fuel pressure delivered to the carburettor
  4. Drive the propeller governor to maintain constant RPM

Explanation

A magneto is a self-contained ignition generator: rotating magnets induce a current in the primary coil, and the sudden collapse of that current when the points open induces a very high voltage in the secondary winding, which is fed to the spark plugs at the instant determined by the timing. Because it generates its own electricity, it keeps firing even if the aircraft's electrical system fails, which is why dual magnetos are fitted.

Question 48Aircraft General Knowledge and Principles of Flight

An aircraft is climbing at a constant indicated airspeed with a constant power setting while the pilot makes no trim change. As altitude increases, the true airspeed will:

  1. Remain constant until the tropopause and then increase
  2. Decrease, because the thinner air reduces the thrust produced by the propeller
  3. Remain constant, because the power setting has not been altered
  4. Increase, because true airspeed is greater than indicated airspeed and the gap widens with altitude Correct answer.

Explanation

Indicated airspeed depends on dynamic pressure, which falls as air density decreases with height; to hold the same indication the aircraft must move faster through the thinner air. Hence true airspeed rises above indicated airspeed as altitude increases, roughly by about 2 per cent per 1,000 ft at lower levels. The aircraft is therefore covering more ground per unit time even though the ASI reads the same.

Question 49Aircraft General Knowledge and Principles of Flight

An aircraft is in a steady level turn. If the bank angle is increased while true airspeed is held constant, the radius of turn will:

  1. Decrease, and the load factor will increase Correct answer.
  2. Decrease, and the load factor will remain unchanged
  3. Remain unchanged, and only the rate of turn will increase
  4. Increase, and the load factor will increase

Explanation

Turn radius is proportional to true airspeed squared divided by g times the tangent of the bank angle, so at constant speed a steeper bank tightens the turn. The load factor equals one divided by the cosine of the bank angle, so it rises as bank increases. Both effects are consequences of the horizontal component of lift having to supply the greater centripetal force.

Question 50Aircraft General Knowledge and Principles of Flight

An aircraft is trimmed for straight-and-level flight and the pilot then extends the flaps without changing power or attitude. Which combination of effects is expected?

  1. Lift decreases, drag decreases, and the nose tends to pitch up
  2. Lift increases at the same angle of attack, drag increases, and the nose tends to pitch down Correct answer.
  3. Lift increases, drag decreases, and the aircraft tends to pitch up
  4. Lift is unchanged, drag increases, and the aircraft tends to pitch down

Explanation

Flap extension increases camber, so the wing produces more lift at the existing angle of attack, and it also raises drag through greater induced and profile drag. The additional lift acts behind the centre of gravity, producing a nose-down pitching moment, and the increased drag may also cause the aircraft to decelerate unless power is added. The pilot must retrim and usually adjust power to hold the flight path.