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Norway CPL Theory study materials
Norway CPL Theory study resources

Norway CPL Theory practice questions

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Question 1Air Law and ATC Procedures

Under Norwegian aviation law, which authority is responsible for issuing a Commercial Pilot Licence (CPL) and for the general oversight of civil aviation in Norway?

  1. The Ministry of Defence
  2. Eurocontrol
  3. Luftfartstilsynet (the Norwegian Civil Aviation Authority) Correct answer.
  4. Avinor AS

Explanation

The Norwegian Civil Aviation Authority, Luftfartstilsynet, is the national regulator that issues pilot licences and conducts oversight of civil aviation. Avinor operates airports and air navigation services but is not the licensing authority.

Question 2Air Law and ATC Procedures

A CPL holder in Norway is exercising the privileges of the licence. Which document must the pilot normally have available for inspection during flight?

  1. The aircraft insurance policy only
  2. The air operator's marketing brochure
  3. The pilot licence and valid medical certificate Correct answer.
  4. The aircraft maintenance programme

Explanation

A pilot exercising licence privileges must be able to present the licence together with a valid medical certificate when requested by an authorised person. These are the personal documents that establish the privilege and fitness to fly.

Question 3Air Law and ATC Procedures

In the context of ICAO annexes adopted into Norwegian regulations, what is the primary purpose of Annex 2 (Rules of the Air)?

  1. To standardise aircraft maintenance schedules
  2. To regulate the licensing of air traffic controllers
  3. To set airworthiness certification standards
  4. To define the rules governing the conduct of flights, including right-of-way and light signals Correct answer.

Explanation

ICAO Annex 2 contains the Rules of the Air, covering matters such as right-of-way, minimum heights, cruising levels and interception signals. It governs how flights are conducted rather than aircraft design or personnel licensing.

Question 4Air Law and ATC Procedures

Two aircraft are approaching head-on at approximately the same altitude. According to the Rules of the Air, how should each pilot avoid collision?

  1. The faster aircraft maintains course and the slower one descends
  2. Both aircraft turn to the left
  3. Both aircraft turn to the right Correct answer.
  4. Each aircraft climbs to the right

Explanation

When two aircraft are approaching head-on or nearly so and risk of collision exists, each shall alter its heading to the right. This creates a predictable, standardised separation manoeuvre for both pilots.

Question 5Air Law and ATC Procedures

Which class of airspace is generally used to describe controlled airspace in which IFR and VFR flights are both permitted and all flights receive ATC service, but no separation is provided between VFR flights?

  1. Class A
  2. Class C Correct answer.
  3. Class G
  4. Class F

Explanation

Class C airspace permits both IFR and VFR flights and provides separation between IFR and VFR, but not between VFR flights themselves. Class A permits only IFR, while Class G is uncontrolled.

Question 6Air Law and ATC Procedures

What does the abbreviation ATIS stand for in air traffic services?

  1. Air Traffic Identification System
  2. Approach Traffic Integration Standard
  3. Automatic Terminal Information Service Correct answer.
  4. Aerodrome Traffic Instruction Sheet

Explanation

ATIS is the Automatic Terminal Information Service, a continuous recorded broadcast of routine aerodrome information such as weather, runway in use and pressure settings. Pilots include the current ATIS letter in their first contact with ATC.

Question 7Air Law and ATC Procedures

A pilot on an IFR flight in controlled airspace receives a clearance with an altitude restriction. What is the pilot's obligation regarding that clearance?

  1. The pilot may deviate at any time without notifying ATC
  2. The pilot may ignore altitude restrictions if weather permits
  3. The pilot must comply unless an amended clearance is obtained or an emergency justifies deviation Correct answer.
  4. The pilot may comply only when radar coverage exists

Explanation

An ATC clearance must be complied with, and any deviation requires an amended clearance except in an emergency. In an emergency the pilot may deviate but must inform ATC as soon as practicable.

Question 8Air Law and ATC Procedures

An aircraft is on final approach and receives a steady red light signal from the aerodrome control tower. What does this signal mean?

  1. Aerodrome unsafe; do not land
  2. Cleared to land
  3. Give way to other aircraft and continue circling Correct answer.
  4. Continue approach, land at your discretion

Explanation

A steady red light directed at an aircraft in flight means 'give way to other aircraft and continue circling.' A steady green light means cleared to land. Flashing red means the aerodrome is unsafe and the aircraft must not land.

Question 9Air Law and ATC Procedures

Under the Rules of the Air, what is the minimum horizontal distance an aircraft must maintain from other aircraft when flying in formation unless otherwise authorised?

  1. 100 m
  2. 500 m
  3. 1 NM
  4. A formation may only be flown as pre-arranged by the pilots concerned Correct answer.

Explanation

Formation flight must be pre-arranged between the pilots concerned, and the aircraft then operate as a single unit for separation purposes. Fixed lateral distances do not apply within an authorised formation.

Question 10Air Law and ATC Procedures

When must a pilot file a flight plan for a flight within Norwegian airspace?

  1. Never, because flight plans are optional in all cases
  2. Whenever the flight will be conducted under IFR in controlled airspace or crosses an international border Correct answer.
  3. Only when flying above FL 195
  4. Only when the flight exceeds 50 km

Explanation

A flight plan must be submitted for IFR flights in controlled airspace and for flights crossing international borders, among other cases. It provides ATC with the information needed for coordination and search and rescue.

Question 11Air Law and ATC Procedures

An aircraft is overtaking another aircraft in flight. Which aircraft has the right-of-way, and on which side should the overtaking aircraft pass?

  1. The aircraft being overtaken has right-of-way, and the overtaking aircraft passes on the right Correct answer.
  2. The overtaking aircraft has right-of-way and may pass on either side
  3. The aircraft being overtaken has right-of-way, and the overtaking aircraft passes on the left
  4. The faster aircraft always has right-of-way

Explanation

The aircraft being overtaken has the right-of-way, and the overtaking aircraft must keep clear by passing on the right. This ensures a predictable and consistent overtaking geometry.

Question 12Air Law and ATC Procedures

What is the purpose of a clearance limit in an IFR clearance?

  1. To define the point to which the aircraft is cleared and beyond which a further clearance is required Correct answer.
  2. To indicate the minimum visibility for take-off
  3. To define the aircraft's maximum cruising speed
  4. To specify the maximum fuel the aircraft may carry

Explanation

The clearance limit is the point to which an aircraft is cleared, and the pilot may not proceed beyond it without a further clearance. It is a fundamental element of IFR clearances for ensuring separation.

Question 13Air Law and ATC Procedures

An aircraft is flying VFR in Class G airspace in Norway. Which statement best describes the traffic information and collision avoidance responsibility?

  1. The pilot is separated from IFR traffic by ATC
  2. The pilot is responsible for collision avoidance and traffic information may not be provided Correct answer.
  3. The pilot must always fly IFR in Class G
  4. ATC provides full separation from all other traffic

Explanation

In Class G airspace, ATC does not provide separation and traffic information may not be available, so the pilot is responsible for collision avoidance. This is a key difference from controlled airspace.

Question 14Air Law and ATC Procedures

Which of the following best describes the role of a 'read-back' of an ATC clearance?

  1. It replaces the need for a flight plan
  2. It transfers responsibility for separation to the pilot
  3. It confirms that the pilot has correctly received and understood the clearance Correct answer.
  4. It is required only for VFR flights

Explanation

Read-back allows ATC to verify that the pilot has correctly received and understood the clearance, reducing the risk of misunderstanding. It does not transfer separation responsibility or replace other requirements.

Question 15Air Law and ATC Procedures

What is the meaning of the term 'SERA' in the context of European and Norwegian air law?

  1. Standard Equipment Requirements for Aircraft
  2. Safety Evaluation and Reporting Agency
  3. Standard European Rules of the Air Correct answer.
  4. Scandinavian Emergency Response Agreement

Explanation

SERA stands for the Standard European Rules of the Air, which harmonise rules of the air across Europe and are implemented in Norwegian regulations. They cover matters such as right-of-way, light signals and flight rules.

Question 16Air Law and ATC Procedures

A pilot flying in controlled airspace experiences a two-way radio communication failure. Under the applicable rules, what is the pilot expected to do?

  1. Turn back to the departure aerodrome regardless of circumstances
  2. Descend immediately to the surface
  3. Continue to the destination and land immediately without any further action
  4. Follow the published communication failure procedures, including squawking the appropriate code and continuing according to the last clearance Correct answer.

Explanation

On communication failure the pilot should follow the published procedures, which include setting the appropriate transponder code and continuing in accordance with the last received clearance or the applicable rules. This allows ATC to predict the aircraft's behaviour.

Question 17Air Law and ATC Procedures

An aircraft is on the ground and receives a flashing red light signal from the tower. What does this signal mean?

  1. Stop Correct answer.
  2. Cleared to taxi
  3. Cleared for take-off
  4. Taxi clear of the runway in use

Explanation

For an aircraft on the ground, a flashing red light signal means 'stop'. A steady red light means 'taxi clear of the runway in use', which is different.

Question 18Air Law and ATC Procedures

Two aircraft are converging at approximately the same altitude; one is a glider and the other is a powered aircraft. Which aircraft has the right-of-way under the Rules of the Air?

  1. Neither; both must turn right
  2. The aircraft with the higher speed
  3. The powered aircraft
  4. The glider Correct answer.

Explanation

Under the right-of-way rules, a glider has the right-of-way over a powered aircraft. This reflects the glider's limited ability to manoeuvre compared with a powered aircraft.

Question 19Air Law and ATC Procedures

A pilot is planning a flight that will enter a restricted area depicted on the aeronautical chart. What is the correct action?

  1. Enter only if flying IFR
  2. Enter only at night
  3. Enter the area without restriction because it is only advisory
  4. Obtain permission from the controlling authority before entering, or remain clear of the area Correct answer.

Explanation

Restricted areas are established for safety or security reasons, and entry is only permitted with the permission of the controlling authority. Otherwise the pilot must remain clear of the area.

Question 20Air Law and ATC Procedures

An aircraft is intercepted by another aircraft and the intercepting pilot rocks the wings and then makes a slow level turn to the right. What is the intercepting pilot signalling?

  1. You may proceed
  2. Descend and proceed to the nearest aerodrome
  3. Land immediately
  4. Follow me Correct answer.

Explanation

In the standard interception signals, rocking the wings followed by a slow level turn onto the desired heading means 'follow me'. The intercepted aircraft should acknowledge and follow.

Question 21Aircraft General Knowledge – Airframe, Systems, Electrics, Powerplant

On a typical light aeroplane, what is the primary function of the empennage?

  1. To house the fuel tanks and baggage compartment
  2. To absorb landing loads through the main gear attachments
  3. To generate the majority of the lift required for flight
  4. To provide longitudinal and directional stability and control Correct answer.

Explanation

The empennage consists of the horizontal and vertical stabilisers plus their control surfaces, the elevator and rudder. These provide pitch and yaw stability and allow the pilot to control the aircraft about the lateral and normal axes. Lift is generated mainly by the wing, not the tail surfaces.

Question 22Aircraft General Knowledge – Airframe, Systems, Electrics, Powerplant

Which structural component of a semi-monocoque wing carries the bending loads along the span?

  1. The leading-edge skin
  2. The wing spar Correct answer.
  3. The aileron hinge bracket
  4. The wing root fairing

Explanation

The spar is the main spanwise beam of the wing and is designed to carry bending moments and shear from the lift distribution. Skin and stringers contribute torsional stiffness and some bending, but the spar is the primary bending member. Fairings and brackets are secondary or local fittings.

Question 23Aircraft General Knowledge – Airframe, Systems, Electrics, Powerplant

In a cable-and-pulley primary flight control system, what is the purpose of a turnbuckle?

  1. To adjust and maintain cable tension Correct answer.
  2. To disconnect the control column during maintenance
  3. To limit the maximum travel of the control surface
  4. To measure the cable tension during flight

Explanation

A turnbuckle is a threaded fitting that joins two cable ends and allows the rigging tension to be set and locked with safety wire. Correct tension prevents cable slack and excessive control-surface free play. Travel limits are set by stops, not turnbuckles.

Question 24Aircraft General Knowledge – Airframe, Systems, Electrics, Powerplant

What happens to an aeroplane's hydraulic system if a hydraulic fuse senses a large downstream leak?

  1. It dumps all remaining fluid overboard to reduce fire risk
  2. It automatically switches the affected system to pneumatic operation
  3. It increases pump output to compensate for the lost fluid
  4. It shuts off flow to the leaking branch to preserve pressure for the rest of the system Correct answer.

Explanation

A hydraulic fuse is a flow-sensitive valve that closes when it detects abnormally high flow, isolating the leaking section. This conserves fluid and pressure so other users of the same system can continue to operate. It does not boost pump output or dump fluid.

Question 25Aircraft General Knowledge – Airframe, Systems, Electrics, Powerplant

On a light aircraft with a constant-volume (non-regulated) hydraulic system, how is excessive pressure normally relieved?

  1. Through a pressure relief valve returning fluid to the reservoir Correct answer.
  2. By the pump automatically reducing its displacement
  3. By venting hydraulic fluid overboard through the filler cap
  4. Through the accumulator expanding to absorb all excess pressure

Explanation

A constant-volume pump delivers a fixed flow, so a relief valve must open at a set pressure and bypass fluid back to the reservoir to protect the system. The accumulator smooths pressure fluctuations but cannot absorb unlimited flow. Displacement control belongs to variable-volume pumps.

Question 26Aircraft General Knowledge – Airframe, Systems, Electrics, Powerplant

What is the main purpose of a bleed-air check valve in a pneumatic system?

  1. To allow flow in one direction only and prevent reverse flow Correct answer.
  2. To filter particulate contamination from the air
  3. To reduce bleed pressure to cabin altitude pressure
  4. To regulate the temperature of the bleed air

Explanation

A check valve is a one-way valve that permits flow in the intended direction and blocks reverse flow, protecting the source from back-pressure. Temperature control is done by precoolers and valves, and pressure regulation by pressure-regulating valves. Filtration is a separate function.

Question 27Aircraft General Knowledge – Airframe, Systems, Electrics, Powerplant

An aircraft electrical system uses a 28 V DC bus. What does the term 'bus bar' describe?

  1. A sensor that measures current in the generator feeder
  2. A switch that disconnects the battery during engine start
  3. A device that converts AC to DC for the battery
  4. A common conductor that distributes electrical power to multiple circuits Correct answer.

Explanation

A bus bar is a common distribution point to which several circuits are connected, allowing one source to feed many loads. It is a conductor, not a converter or a protective device. Circuit protection is provided by separate breakers or fuses.

Question 28Aircraft General Knowledge – Airframe, Systems, Electrics, Powerplant

Why is a shunt used in an aircraft DC generation system?

  1. To limit the generator output voltage to 28 V
  2. To store electrical energy for emergency use
  3. To rectify alternating current from the alternator
  4. To produce a small voltage proportional to the current for indication Correct answer.

Explanation

A shunt is a low-resistance element placed in series with the load so that the small voltage drop across it represents the current flowing. This millivolt signal drives the ammeter or loadmeter. Voltage regulation and rectification are separate functions.

Question 29Aircraft General Knowledge – Airframe, Systems, Electrics, Powerplant

In a lead-acid aircraft battery, what is the effect of a low electrolyte level?

  1. No effect as long as the battery voltage is correct
  2. Reduced capacity and risk of plate damage from exposure Correct answer.
  3. Improved cranking performance in cold weather
  4. Increased capacity because of higher acid concentration

Explanation

The electrolyte must cover the plates for the chemical reaction to occur over the full plate area. If the level falls, active plate area is lost, capacity drops and exposed plates can be permanently damaged. Voltage alone does not confirm the electrolyte level is adequate.

Question 30Aircraft General Knowledge – Airframe, Systems, Electrics, Powerplant

What is the purpose of a freewheel (overrunning) unit in an engine starting system?

  1. To reduce the starter current during the initial engagement
  2. To disengage the starter from the engine once the engine runs faster than the starter Correct answer.
  3. To lock the starter permanently to the engine crankshaft
  4. To prevent the starter from turning in the correct direction

Explanation

The freewheel allows the starter to drive the engine during starting but overruns when the engine accelerates beyond starter speed. This prevents the engine from driving and damaging the starter motor. It does not reduce starting current or reverse the direction of rotation.

Question 31Aircraft General Knowledge – Airframe, Systems, Electrics, Powerplant

On a horizontally opposed piston engine, what does the camshaft control?

  1. The oil pressure supplied to the bearings
  2. The ignition timing of the spark plugs
  3. The opening and closing times of the inlet and exhaust valves Correct answer.
  4. The fuel-air mixture strength delivered by the carburettor

Explanation

The camshaft carries lobes that actuate the valve train, setting valve opening and closing relative to crankshaft position. Ignition timing is controlled by magnetos or the ignition system, and mixture by the fuel metering unit. Oil pressure is set by the oil pump and relief valve.

Question 32Aircraft General Knowledge – Airframe, Systems, Electrics, Powerplant

What is the function of the magneto in a piston aero-engine ignition system?

  1. To regulate the alternator output voltage
  2. To generate the high-tension voltage that fires the spark plugs Correct answer.
  3. To supply current to the starter motor
  4. To advance the ignition timing as altitude increases

Explanation

A magneto is a self-contained generator that produces high voltage for the spark plugs, independent of the aircraft battery. This independence is a key reliability feature. Voltage regulation of the alternator and starter supply are unrelated functions.

Question 33Aircraft General Knowledge – Airframe, Systems, Electrics, Powerplant

Why does a piston engine require an oil cooler in the lubrication system?

  1. To separate air from the oil after the scavenge pump
  2. To remove heat absorbed by the oil from the engine and maintain viscosity Correct answer.
  3. To increase oil pressure at high power settings
  4. To filter metal particles from the oil

Explanation

Oil absorbs heat from bearings and cylinders, and its viscosity falls as temperature rises. The cooler rejects this heat so the oil stays within a viscosity range that maintains an adequate film. Filtering and air separation are handled by other components.

Question 34Aircraft General Knowledge – Airframe, Systems, Electrics, Powerplant

A normally aspirated piston engine is fitted with a fixed-pitch propeller. During a climb at constant throttle, what happens to manifold pressure as altitude increases?

  1. It increases because the mixture leans automatically
  2. It increases because the engine speeds up
  3. It remains constant because the throttle is unchanged
  4. It decreases because ambient pressure falls Correct answer.

Explanation

Manifold pressure reflects the absolute pressure in the induction system, which is limited by ambient pressure. As the aircraft climbs, ambient pressure falls, so manifold pressure falls even with a fixed throttle. Engine speed and mixture do not raise manifold pressure above ambient.

Question 35Aircraft General Knowledge – Airframe, Systems, Electrics, Powerplant

What is detonation in a piston aero-engine?

  1. Combustion that occurs after the exhaust valve opens
  2. Pre-ignition caused by a glowing spark plug electrode
  3. Explosive, uncontrolled combustion of the end gas ahead of the flame front Correct answer.
  4. A lean mixture burning slowly and smoothly

Explanation

Detonation is the spontaneous, explosive ignition of the unburned fuel-air charge ahead of the normal flame front, driven by high pressure and temperature. It causes a sharp pressure rise, roughness and possible engine damage. Pre-ignition is a distinct phenomenon with a different cause.

Question 36Aircraft General Knowledge – Airframe, Systems, Electrics, Powerplant

An engine monitor shows cylinder head temperature rising rapidly while oil temperature remains normal during a climb. Which action is most appropriate?

  1. Increase power to improve cooling airflow over the engine
  2. Lean the mixture further to reduce fuel consumption
  3. Close the cowl flaps to retain cooling air
  4. Reduce power and enrich the mixture to lower combustion temperatures Correct answer.

Explanation

A rapid rise in cylinder head temperature with normal oil temperature suggests high combustion temperatures, often from a lean mixture or high power at low airspeed. Reducing power and enriching the mixture lowers peak combustion temperature. Closing cowl flaps would worsen cooling.

Question 37Aircraft General Knowledge – Airframe, Systems, Electrics, Powerplant

In a turbocharged piston engine, what is the purpose of the wastegate?

  1. To bypass the oil cooler when oil is cold
  2. To dump excess fuel when the mixture is too rich
  3. To control the exhaust gas flow through the turbine and thus limit boost Correct answer.
  4. To cool the compressed air before it enters the throttle body

Explanation

The wastegate regulates how much exhaust gas passes through the turbine. By diverting exhaust around the turbine, it limits turbine speed and compressor boost to the desired manifold pressure. It does not meter fuel, cool the charge or affect oil cooling.

Question 38Aircraft General Knowledge – Airframe, Systems, Electrics, Powerplant

What is the purpose of a constant-speed propeller governor?

  1. To feather the propeller automatically at every shutdown
  2. To synchronise the propeller with the magneto timing
  3. To vary blade pitch so the propeller absorbs the selected engine power at a set RPM Correct answer.
  4. To limit engine RPM by restricting fuel flow

Explanation

The governor senses engine speed and adjusts propeller blade pitch to keep RPM at the value selected by the pilot. It changes the load on the engine rather than the fuel supply. Feathering is a separate pilot-selected function, and magneto timing is unrelated.

Question 39Aircraft General Knowledge – Airframe, Systems, Electrics, Powerplant

What is the effect of a propeller blade being in coarse pitch at a given RPM?

  1. It produces less thrust and allows higher RPM for the same power
  2. It increases drag and reduces forward speed
  3. It takes a larger bite of air and produces more thrust per revolution Correct answer.
  4. It reverses the direction of propeller rotation

Explanation

Coarse pitch means a larger blade angle, so each revolution advances the blade through a greater air distance and absorbs more power. It is used at high forward speed where a small angle would allow the engine to overspeed. Pitch does not change the direction of rotation.

Question 40Aircraft General Knowledge – Airframe, Systems, Electrics, Powerplant

Which of these describes the purpose of an aircraft's anti-icing system on the wing leading edge?

  1. To increase lift by changing the aerofoil shape
  2. To provide structural stiffening to the leading edge
  3. To prevent ice formation by adding heat or fluid before ice accumulates Correct answer.
  4. To remove ice that has already formed by mechanical breaking

Explanation

Anti-icing systems act before ice forms, using hot air or weeping fluid to keep the surface above freezing or to lower the freezing point. De-icing systems, such as inflatable boots, remove ice after it has formed. Neither function is structural or aerodynamic shaping.

Question 41Aircraft General Knowledge – Airframe, Systems, Electrics, Powerplant

What is the function of the cabin pressure outflow valve?

  1. To regulate the rate at which cabin air leaves, controlling cabin altitude Correct answer.
  2. To shut off engine bleed air in an emergency
  3. To control the temperature of air entering the cabin
  4. To supply bleed air to the air-conditioning packs

Explanation

The outflow valve is the main variable opening through which cabin air escapes to atmosphere. By modulating its position, the pressure controller maintains the selected cabin altitude and rate of change. Temperature and bleed supply are handled by other valves.

Question 42Aircraft General Knowledge – Airframe, Systems, Electrics, Powerplant

An aeroplane has a 24 V battery and a 28 V DC alternator system. What is the role of the battery master relay?

  1. To charge the battery from the alternator at a fixed rate
  2. To protect the alternator from overvoltage
  3. To connect and disconnect the battery from the DC bus Correct answer.
  4. To convert 24 V battery output to 28 V for the bus

Explanation

The battery master relay is a contactor controlled by the battery master switch, connecting the battery to the main bus for starting and emergency power. It does not convert voltage or regulate charging. Overvoltage protection is provided by the voltage regulator or overvoltage relay.

Question 43Aircraft General Knowledge – Airframe, Systems, Electrics, Powerplant

Why are fire detection loops in an engine compartment arranged in a dual-loop configuration?

  1. To double the sensitivity so smaller fires are detected sooner
  2. To provide fault tolerance so a single loop failure does not disable detection Correct answer.
  3. To allow detection of both fire and overheat with one loop
  4. To reduce the total weight of the detection system

Explanation

Dual loops give redundancy: if one loop fails or is damaged, the system can still detect a fire on the remaining loop, often with degraded logic. Sensitivity is not simply doubled, and weight is increased rather than reduced. Detection logic differs between fire and overheat.

Question 44Aircraft General Knowledge – Airframe, Systems, Electrics, Powerplant

What is the purpose of a fuel selector valve in a light aircraft fuel system?

  1. To automatically maintain a constant fuel pressure to the carburettor
  2. To drain water from the lowest point of the system
  3. To measure the quantity of fuel in each tank
  4. To allow the pilot to select which tank supplies the engine Correct answer.

Explanation

The fuel selector valve directs fuel from the chosen tank or tanks to the engine feed line, and may include an OFF position. Pressure regulation is done by the engine-driven pump and relief valve. Quantity indication and water drainage are separate functions.

Question 45Aircraft General Knowledge – Instrumentation

Which instrument in a light aircraft is connected directly to the pitot tube and measures the difference between total pressure and static pressure?

  1. The vertical speed indicator
  2. The turn coordinator
  3. The altimeter
  4. The airspeed indicator Correct answer.

Explanation

The airspeed indicator is the only instrument plumbed to both the pitot tube and the static source, and it displays the difference between total (pitot) pressure and static pressure as indicated airspeed. The altimeter and vertical speed indicator use static pressure only, so they cannot sense ram air from the pitot head.

Question 46Aircraft General Knowledge – Instrumentation

During a climb with the static source blocked, the airspeed indicator will tend to indicate a value that is:

  1. Lower than the actual airspeed Correct answer.
  2. Increasing toward the true airspeed
  3. Higher than the actual airspeed
  4. Unaffected by the static source blockage

Explanation

With the static port blocked, the pressure trapped in the case remains at the level of the altitude where the blockage occurred. As the aircraft climbs, true static pressure falls but the instrument still senses the higher trapped pressure, so the differential across the capsule is smaller than it should be and indicated airspeed reads below the real value.

Question 47Aircraft General Knowledge – Instrumentation

An aircraft on the ground with the altimeter set to the local QNH reads 120 ft. What does this indicate?

  1. The aircraft is standing on terrain about 120 ft above mean sea level Correct answer.
  2. The static port is blocked
  3. The altimeter subscale is set incorrectly
  4. The instrument has a lag error of 120 ft

Explanation

With QNH set, the altimeter indicates elevation above mean sea level, so a reading of 120 ft on the ground means the aerodrome surface is approximately 120 ft above MSL. This is the normal behaviour of a serviceable altimeter and is not an error.

Question 48Aircraft General Knowledge – Instrumentation

What is the purpose of the bimetallic compensator inside a pressure altimeter?

  1. To correct the reading for non-standard QNH
  2. To compensate for temperature-induced elasticity changes in the capsule and linkage Correct answer.
  3. To damp oscillations caused by turbulence
  4. To prevent the mechanism from being damaged at high altitude

Explanation

The elastic properties of the aneroid capsule and the mechanical linkage change with temperature, which would introduce an error in the indicated altitude. A bimetallic strip bends with temperature and offsets this effect so that the altimeter remains accurate across its operating temperature range.

Question 49Aircraft General Knowledge – Instrumentation

In a steady level turn, what does the turn coordinator primarily display?

  1. The angle of bank only
  2. The pitch attitude relative to the horizon
  3. The heading relative to magnetic north
  4. The rate of turn and whether the turn is coordinated Correct answer.

Explanation

The turn coordinator uses a canted gyroscope so that it responds to both yaw and roll, displaying the rate of turn and, through the inclinometer ball, whether the turn is coordinated. It is not an attitude indicator and does not show heading.

Question 50Aircraft General Knowledge – Instrumentation

In a turn indicator driven by an electrically powered gyroscope, the gyro spin axis is deliberately tilted. What is the reason for this?

  1. To make the instrument independent of the electrical supply
  2. To reduce precession during straight flight
  3. To increase the rotor speed
  4. To allow the instrument to sense roll as well as yaw Correct answer.

Explanation

Canting the spin axis means the gyro responds to the roll component of a banked turn as well as to yaw, so the instrument begins to indicate as soon as the aircraft banks. This gives the pilot an immediate indication of turn rate and direction during the entry to a turn.