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CAAP PPL Knowledge Exam study materials
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CAAP PPL Knowledge Exam practice questions

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Question 1Air Law and Philippine Civil Aviation Regulations

Under the Philippine Civil Aviation Regulations, which document primarily prescribes the rules for the issuance of pilot licences and ratings by the Civil Aviation Authority of the Philippines?

  1. Philippine Civil Aviation Regulations Part 61 Correct answer.
  2. Philippine Civil Aviation Regulations Part 11
  3. Philippine Civil Aviation Regulations Part 8
  4. Philippine Civil Aviation Regulations Part 2

Explanation

PCAR Part 61 governs the certification of pilots, flight instructors and ground instructors, including the requirements for licences and ratings. Parts 2 and 11 deal with personnel licensing administration and air traffic services respectively, while Part 8 covers operations of civil aircraft.

Question 2Air Law and Philippine Civil Aviation Regulations

A private pilot licence holder in the Philippines may be compensated for flying under which of the following circumstances?

  1. Sharing the operating expenses of a flight with the passengers Correct answer.
  2. Receiving payment from a company for transporting its executives
  3. Carrying passengers or cargo for hire on a scheduled basis
  4. Serving as pilot in command of an air taxi flight

Explanation

A PPL holder may not act as pilot in command of an aircraft carrying persons or property for compensation or hire, but may share the operating expenses of a flight with the passengers. Any operation for hire or reward requires at least a commercial pilot licence.

Question 3Air Law and Philippine Civil Aviation Regulations

What is the minimum age at which a person may be issued a private pilot licence under the Philippine Civil Aviation Regulations?

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

Explanation

The minimum age for issuance of a private pilot licence is 17 years, although a student pilot may begin training earlier. The 18-year threshold applies to the commercial pilot licence, and 21 years to the airline transport pilot licence.

Question 4Air Law and Philippine Civil Aviation Regulations

For a private pilot licence with a single-engine land aeroplane rating, what is the minimum total flight time required before applying for the licence?

  1. 30 hours
  2. 60 hours
  3. 40 hours Correct answer.
  4. 20 hours

Explanation

The PPL applicant must have logged at least 40 hours of flight time as a pilot, including dual instruction and solo flight time in aeroplanes. This total is the baseline requirement before the skill test may be taken.

Question 5Air Law and Philippine Civil Aviation Regulations

A pilot's medical certificate has expired, but the pilot is otherwise qualified. What is the status of the pilot's licence privileges?

  1. The privileges remain valid for non-commercial flights only
  2. The privileges are suspended until the medical certificate is renewed Correct answer.
  3. The privileges remain fully valid for 30 days after expiry
  4. The privileges remain valid if the pilot flies only with an instructor

Explanation

A pilot licence is valid only when the holder also holds a current medical certificate appropriate to the privileges exercised. Once the medical certificate expires, the pilot may not exercise the licence privileges until it is renewed.

Question 6Air Law and Philippine Civil Aviation Regulations

Which class of medical certificate is required for a private pilot licence holder who is exercising private pilot privileges?

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

Explanation

Private pilot privileges require at least a valid Class 2 medical certificate. A Class 1 certificate is required for commercial and airline transport operations, while a Class 3 certificate is not a category used for pilot licensing in the Philippines.

Question 7Air Law and Philippine Civil Aviation Regulations

A pilot has logged 50 hours of cross-country flight time as pilot in command. What is the minimum cross-country requirement for the private pilot licence?

  1. 3 hours
  2. 5 hours
  3. 20 hours
  4. 10 hours Correct answer.

Explanation

The PPL applicant must have completed at least 10 hours of solo flight time, including a cross-country flight of not less than 270 kilometres with landings at two other aerodromes. The logged 50 hours exceeds the minimum requirement.

Question 8Air Law and Philippine Civil Aviation Regulations

Under the Philippine Civil Aviation Regulations, when must a pilot's logbook entries be made?

  1. Within a reasonable time after the flight Correct answer.
  2. Within 7 days of the flight
  3. At the end of each calendar month
  4. Within 30 days of the flight

Explanation

The regulations require that logbook entries be made within a reasonable time after the flight, ensuring the record reflects the flight accurately. There is no fixed 7-day or 30-day statutory deadline for entries.

Question 9Air Law and Philippine Civil Aviation Regulations

An applicant for a private pilot licence must hold which certificate before beginning solo flight training?

  1. Student pilot certificate Correct answer.
  2. Flight instructor certificate
  3. Recreational pilot certificate
  4. Commercial pilot licence

Explanation

A student pilot certificate is required before a person may fly solo. The certificate is issued upon application and after the required medical certificate is obtained, and it is endorsed for solo privileges by an authorized instructor.

Question 10Air Law and Philippine Civil Aviation Regulations

What is the minimum age for issuance of a student pilot certificate in the Philippines?

  1. 17 years
  2. 15 years
  3. 16 years Correct answer.
  4. 14 years

Explanation

A student pilot certificate may be issued to a person who is at least 16 years old. The private pilot licence requires 17 years, and the commercial pilot licence requires 18 years.

Question 11Air Law and Philippine Civil Aviation Regulations

A pilot's Class 2 medical certificate was issued on 1 March 2024. Assuming no special limitation applies, when does the certificate expire?

  1. 1 March 2027
  2. 1 March 2026 Correct answer.
  3. 1 September 2024
  4. 1 March 2025

Explanation

A Class 2 medical certificate for a pilot under 40 years of age is normally valid for 24 months, expiring on the corresponding date two years after issuance. Special validity periods apply to holders aged 40 and above.

Question 12Air Law and Philippine Civil Aviation Regulations

Which authority in the Philippines is responsible for issuing pilot licences and enforcing the Philippine Civil Aviation Regulations?

  1. Civil Aviation Authority of the Philippines Correct answer.
  2. Philippine Air Force
  3. Manila International Airport Authority
  4. Civil Aeronautics Board

Explanation

The Civil Aviation Authority of the Philippines (CAAP) is the regulatory body that issues pilot licences and enforces the Philippine Civil Aviation Regulations. The Civil Aeronautics Board handles economic regulation of air transport, while airport authorities manage airport operations.

Question 13Air Law and Philippine Civil Aviation Regulations

A pilot intends to fly an aircraft that is not covered by the ratings on the pilot's licence. What is the correct course of action?

  1. Log the flight as dual instruction
  2. Fly the aircraft only during daylight hours
  3. Obtain the appropriate rating before acting as pilot in command Correct answer.
  4. Fly the aircraft if an instructor is on board

Explanation

A pilot may act as pilot in command only of aircraft for which the pilot holds the appropriate category, class and type ratings. The pilot must first obtain the rating through the required training and testing.

Question 14Air Law and Philippine Civil Aviation Regulations

What is the purpose of a biennial flight review under the Philippine Civil Aviation Regulations?

  1. To demonstrate that the pilot remains proficient and current Correct answer.
  2. To qualify the pilot for a new aircraft type rating
  3. To satisfy insurance company requirements only
  4. To renew the medical certificate

Explanation

The biennial flight review is a proficiency check conducted by an authorized instructor to confirm that the pilot retains the knowledge and skill required for the privileges of the licence. It is a regulatory currency requirement, not a medical or type-rating process.

Question 15Air Law and Philippine Civil Aviation Regulations

A private pilot has not flown as pilot in command for 18 months. What is required before carrying passengers?

  1. Nothing, provided the licence and medical certificate are valid
  2. An additional 100 hours of flight time
  3. A new skill test with the Authority
  4. A satisfactory biennial flight review and recent experience Correct answer.

Explanation

To carry passengers, a pilot must have completed a biennial flight review and satisfied the recent flight experience requirements, such as the required takeoffs and landings within the preceding 90 days. A lapse in flying does not automatically invalidate the licence but does affect passenger-carrying currency.

Question 16Air Law and Philippine Civil Aviation Regulations

Which of the following is a required document that must be carried on board an aircraft during flight in the Philippines?

  1. The aircraft maintenance schedule
  2. The aircraft certificate of airworthiness Correct answer.
  3. The pilot's training records
  4. The pilot's logbook

Explanation

The certificate of airworthiness and certificate of registration, together with the pilot's licence and medical certificate, must be carried on board. Logbooks and maintenance schedules are records kept on the ground rather than documents required on board.

Question 17Air Law and Philippine Civil Aviation Regulations

An aircraft's certificate of airworthiness has expired. What is the status of the aircraft?

  1. It may not be flown except under a special flight permit Correct answer.
  2. It may be flown if the pilot holds an instrument rating
  3. It may be flown for maintenance test flights without restriction
  4. It may be flown for private purposes only

Explanation

An aircraft may not be operated unless it holds a valid certificate of airworthiness. A special flight permit may be issued for specific purposes such as maintenance flights or delivery, but ordinary flight is prohibited.

Question 18Air Law and Philippine Civil Aviation Regulations

What is the standard altimeter setting procedure when flying below the transition altitude in Philippine airspace?

  1. Set the altimeter to zero before takeoff
  2. Set the altimeter to the aircraft's field elevation
  3. Set the local altimeter setting reported by the aerodrome Correct answer.
  4. Set the standard pressure of 1013.2 hPa

Explanation

Below the transition altitude, the altimeter is set to the local altimeter setting (QNH) so that the altimeter indicates altitude above mean sea level. The standard pressure of 1013.2 hPa is used at and above the transition level.

Question 19Air Law and Philippine Civil Aviation Regulations

Which body issues the NOTAMs and aeronautical information publications used by pilots in the Philippines?

  1. Civil Aeronautics Board
  2. Department of Transportation
  3. Civil Aviation Authority of the Philippines Correct answer.
  4. Philippine Atmospheric, Geophysical and Astronomical Services Administration

Explanation

The Civil Aviation Authority of the Philippines publishes aeronautical information, including NOTAMs and the Aeronautical Information Publication, through its aeronautical information service. The other agencies perform economic regulation, transport policy and weather services respectively.

Question 20Air Law and Philippine Civil Aviation Regulations

A pilot operating under visual flight rules in controlled airspace must maintain which minimum flight visibility in general?

  1. 1.5 kilometres
  2. 3 kilometres
  3. 5 kilometres Correct answer.
  4. 8 kilometres

Explanation

VFR flight in controlled airspace generally requires a flight visibility of at least 5 kilometres and cloud clearance of 1,500 metres horizontally and 300 metres vertically from cloud. Lower minima may apply in special VFR or certain classes of airspace.

Question 21Air Law and Philippine Civil Aviation Regulations

What does a red traffic light signal directed at an aircraft on the ground by the aerodrome control tower mean?

  1. Cleared for takeoff
  2. Cleared to taxi
  3. Stop Correct answer.
  4. Return to starting point

Explanation

A steady red light signal directed at an aircraft on the ground means stop. A flashing red light means taxi clear of the runway in use, while a green light means cleared for takeoff or to taxi.

Question 22Air Law and Philippine Civil Aviation Regulations

An aircraft is overtaking another aircraft in flight. Which aircraft has the right of way?

  1. The aircraft with the higher category
  2. The overtaking aircraft
  3. The faster aircraft
  4. The aircraft being overtaken Correct answer.

Explanation

The aircraft being overtaken has the right of way, and the overtaking aircraft must keep clear by altering heading to the right. Converging aircraft rules assign priority differently, but the overtaking rule always favours the aircraft being overtaken.

Question 23Air Law and Philippine Civil Aviation Regulations

Two aircraft are approaching head-on, or nearly so, and a risk of collision exists. What action should each pilot take?

  1. Both alter heading to the left
  2. Both alter heading to the right Correct answer.
  3. The faster aircraft maintains course
  4. The lower aircraft climbs

Explanation

When aircraft approach head-on or nearly head-on with risk of collision, each pilot must alter heading to the right. This ensures both aircraft pass clear of each other on the same side.

Question 24Air Law and Philippine Civil Aviation Regulations

An aircraft is experiencing an in-flight emergency and the pilot needs to deviate from air traffic control instructions. What is the correct procedure?

  1. Land immediately at the nearest aerodrome without notifying ATC
  2. Advise ATC of the emergency and obtain an amended clearance as soon as practicable Correct answer.
  3. Turn off the transponder to avoid interference
  4. Continue to comply with all instructions until landing

Explanation

In an emergency, the pilot in command may deviate from ATC instructions to the extent necessary for safety and must advise ATC as soon as practicable. ATC will then provide priority and amended clearances.

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

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

  1. Intake stroke Correct answer.
  2. Compression stroke
  3. Power stroke
  4. Exhaust stroke

Explanation

The intake stroke draws the fuel-air mixture into the cylinder, so the intake valve is open while the piston descends. The other three strokes involve closed intake valve, with compression and power on the up-and-down motion after ignition and exhaust expelling burned gases.

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

What is the primary function of the carburetor in a normally aspirated light aircraft engine?

  1. To meter and mix fuel with air in the correct proportion for combustion Correct answer.
  2. To increase the pressure of the fuel delivered to the cylinders
  3. To cool the engine oil before it returns to the sump
  4. To regulate the voltage produced by the alternator

Explanation

The carburetor atomizes fuel and mixes it with incoming air at a ratio suitable for combustion across the operating range. It relies on venturi depression and metering jets rather than pressurizing fuel, which is the job of the fuel pump.

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

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

  1. Altimeter
  2. Turn coordinator
  3. Vertical speed indicator
  4. Airspeed indicator Correct answer.

Explanation

The airspeed indicator compares ram air pressure from the pitot tube against static pressure to display indicated airspeed. The altimeter and vertical speed indicator use static pressure alone, and the turn coordinator uses a gyro.

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

What is indicated by the green arc on an aircraft engine tachometer?

  1. The idle speed range
  2. The range in which continuous operation is prohibited
  3. The normal operating speed range Correct answer.
  4. The maximum allowable speed for takeoff only

Explanation

On engine and airspeed gauges, the green arc marks the normal operating range. A yellow arc would indicate caution, and a red line marks the maximum limit, so the green arc is where routine operation is expected.

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

Which of the following best describes the purpose of the magnetos in a reciprocating aircraft engine?

  1. They control the pitch of the propeller blades
  2. They convert alternating current from the alternator into direct current
  3. They regulate the oil pressure supplied to the bearings
  4. They supply the high-voltage spark to the spark plugs independently of the aircraft battery Correct answer.

Explanation

Magnetos are self-contained ignition devices that generate their own electrical energy and deliver high-voltage pulses to the spark plugs, so the engine keeps running even if the electrical system fails. The redundancy of dual magnetos improves reliability and combustion efficiency.

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

What is the function of the master switch in a light aircraft electrical system?

  1. It selects which magneto fires during engine start
  2. It controls the fuel mixture supplied to the carburetor
  3. It connects or disconnects the battery and alternator from the main electrical bus Correct answer.
  4. It adjusts the trim tab position for pitch control

Explanation

The master switch is the main gate that ties the battery and the generator/alternator to the electrical bus, energizing the aircraft's electrical loads. It is normally split into a battery side and an alternator side so each source can be controlled.

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

In a light aircraft, which control surface is primarily used to control roll about the longitudinal axis?

  1. Rudder
  2. Ailerons Correct answer.
  3. Elevator
  4. Flaps

Explanation

Ailerons are mounted on the trailing edge of each wing and move differentially to raise one wing and lower the other, producing roll about the longitudinal axis. The elevator controls pitch and the rudder controls yaw.

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

What is the purpose of the engine oil in a reciprocating aircraft engine?

  1. To pressurize the cabin for high-altitude flight
  2. To lubricate moving parts, assist cooling, and help seal and clean the engine Correct answer.
  3. To generate the spark that ignites the fuel-air mixture
  4. To provide the fuel for combustion in the cylinders

Explanation

Oil performs several functions: it reduces friction between moving parts, carries heat away from hot components, helps seal piston rings, and suspends contaminants for removal by the filter. It does not participate in combustion or ignition.

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

An aircraft is climbing at a constant indicated airspeed. As altitude increases, what happens to the true airspeed?

  1. True airspeed decreases because temperature decreases
  2. True airspeed remains exactly equal to indicated airspeed
  3. True airspeed increases because air density decreases Correct answer.
  4. True airspeed decreases because air density decreases

Explanation

Indicated airspeed reflects dynamic pressure, which depends on air density. As altitude rises, density falls, so a given indicated airspeed corresponds to a higher true airspeed through the thinner air.

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

If the static port becomes blocked while the aircraft is climbing, what will the airspeed indicator most likely show?

  1. An airspeed higher than actual because trapped static pressure is higher than ambient Correct answer.
  2. A correct airspeed because the pitot tube remains clear
  3. A gradual decrease to zero regardless of actual speed
  4. An airspeed lower than actual because trapped static pressure is lower than ambient

Explanation

With a blocked static port, the trapped static pressure stays at the value from the altitude where the blockage occurred. As the aircraft climbs, ambient pressure drops but pitot pressure still reflects true dynamic pressure plus the higher trapped static value, so the indicator over-reads airspeed.

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

During a preflight inspection, the pilot finds that the carburetor heat control is stuck in the cold position. What is the most significant operational consequence?

  1. The magnetos will not produce a spark during start
  2. The engine will run excessively rich at all power settings
  3. The fuel pump will not deliver fuel to the carburetor
  4. The pilot cannot apply carburetor heat to clear ice that may form in the venturi Correct answer.

Explanation

Carburetor heat routes warm air into the induction system to melt or prevent ice in the venturi and throttle area. If the control is stuck cold, the pilot loses the ability to respond to carburetor icing, which can cause a serious loss of power.

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

Why does an aircraft engine use two independent magnetos rather than a single ignition source?

  1. To reduce the octane requirement of the fuel
  2. To provide redundancy and more complete combustion from dual spark plugs Correct answer.
  3. To eliminate the need for a battery during normal operation only
  4. To double the engine's compression ratio

Explanation

Dual magnetos each fire one of two spark plugs per cylinder. This gives redundancy if one system fails and promotes faster, more complete combustion, which slightly improves performance. The engine can run on one magneto, though with reduced efficiency.

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

During a magneto check, the engine runs rough when the ignition switch is set to the LEFT position. What does this most likely indicate?

  1. The carburetor heat is stuck in the on position
  2. A fault in the right magneto or its associated spark plugs and leads Correct answer.
  3. A fault in the left magneto only
  4. The engine is operating normally and the roughness is expected

Explanation

Selecting LEFT grounds the right magneto so only the left one fires. If the engine runs rough in that configuration, the operating left magneto is likely faulty, or a plug or lead in its circuit is failing. The rough running reflects the loss of the grounded magneto's contribution.

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

The exhaust gas temperature (EGT) gauge in a light aircraft is most useful to the pilot for which purpose?

  1. Indicating the fuel flow to the carburetor
  2. Identifying the peak EGT for leaning the mixture Correct answer.
  3. Monitoring oil pressure during descent
  4. Measuring cylinder head temperature for cooling checks

Explanation

EGT peaks as the mixture passes through the stoichiometric ratio, so the pilot can lean to a target value relative to peak EGT for economy or power. Cylinder head temperature, oil pressure, and fuel flow are shown on separate gauges.

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

What happens to the mixture strength if the throttle is opened rapidly from idle in a float-type carburetor?

  1. The mixture becomes richer because the venturi depression increases
  2. The mixture strength is unaffected by throttle movement
  3. The mixture momentarily leans as airflow increases faster than fuel flow Correct answer.
  4. The mixture momentarily becomes excessively rich

Explanation

When the throttle opens quickly, air flow rises immediately while fuel, which is heavier and must be drawn through the metering jets, lags behind. The result is a brief lean condition, which is why accelerator pumps are fitted to some carburetors.

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

An aircraft's ammeter shows a continuous discharge with the engine running above idle. Which interpretation is most appropriate?

  1. The master switch is turned off
  2. The battery is fully charged and the system is normal
  3. The alternator or generator is not supplying enough current to meet the electrical load Correct answer.
  4. The fuel mixture is too lean for the power setting

Explanation

With the engine running, the charging source should carry the electrical loads and recharge the battery, showing a positive or near-zero indication. A sustained discharge means the alternator/generator output is insufficient or has failed, and the battery is being drained.

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

What is the purpose of the pressure relief valve in an aircraft engine's lubrication system?

  1. To increase oil pressure at high altitude
  2. To filter contaminants from the oil
  3. To limit maximum oil pressure by bypassing excess oil back to the sump Correct answer.
  4. To cool the oil before it enters the engine

Explanation

The relief valve opens when oil pressure exceeds a set value, diverting excess oil away from the galleries to prevent damage to seals and lines. Filtration and cooling are handled by the oil filter and oil cooler respectively.

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

A pilot notices that the fuel pressure gauge reads low during climb with the electric boost pump off. Which action is most consistent with standard operating practice?

  1. Ignore the indication because low pressure is normal in a climb
  2. Reduce engine power and continue the climb with the boost pump off
  3. Lean the mixture further to reduce fuel demand
  4. Turn on the electric fuel pump and investigate the cause of the low pressure Correct answer.

Explanation

Low fuel pressure in a climb may signal a failing engine-driven pump or a vapor lock risk. Selecting the electric boost pump restores fuel pressure and is a standard response while the cause is investigated.

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

What is the function of the voltage regulator in an aircraft electrical system?

  1. It limits the current drawn by the starter motor
  2. It stores electrical energy for use during engine start
  3. It controls the output voltage of the alternator or generator to a safe value Correct answer.
  4. It converts direct current to alternating current for the avionics

Explanation

The voltage regulator senses system voltage and adjusts the field current so the generator or alternator output stays within limits, protecting the battery and electrical equipment. Energy storage is the battery's role, not the regulator's.

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

During a run-up, the pilot applies carburetor heat and observes a slight drop in RPM. What does this indicate?

  1. The engine is overheating and needs to be shut down
  2. The carburetor is icing and the heat is clearing it
  3. The carburetor heat system is functioning and the enriched mixture causes a small power loss Correct answer.
  4. The magnetos are failing and require maintenance

Explanation

Applying carburetor heat normally causes a small RPM drop because the warmer, less dense air and the resulting richer mixture reduce power slightly. That expected drop confirms the heat system is delivering warm air to the induction.

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

In a constant-speed propeller system, what is the function of the propeller governor?

  1. It adjusts the fuel mixture automatically with altitude
  2. It sets the ignition timing based on manifold pressure
  3. It controls the rate of flap extension
  4. It regulates oil flow to the propeller hub to maintain the selected RPM Correct answer.

Explanation

The governor senses engine RPM and meters oil to or from the propeller hub, changing blade angle to hold the selected speed. It is independent of the fuel, ignition, and flap systems.

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

An aircraft's altimeter is set to the local altimeter setting but reads 200 feet higher than the known field elevation when the aircraft is on the ground. Which explanation is most likely?

  1. The pitot tube is blocked
  2. The altimeter setting was entered incorrectly by a large amount
  3. The static system has a small leak or the instrument has a calibration error Correct answer.
  4. The vertical speed indicator is faulty

Explanation

With the correct altimeter setting, the altimeter should read field elevation within tolerance. A consistent 200-foot error suggests a static system leak, trapped pressure, or instrument calibration error rather than a gross setting mistake.

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

A pilot observes that cylinder head temperature is rising toward the upper limit in a climb. Which combination of actions best addresses this while maintaining climb performance?

  1. Close the cowl flaps and reduce power
  2. Increase the climb rate and reduce the mixture to save fuel
  3. Lean the mixture and reduce airspeed to reduce drag
  4. Enrich the mixture and increase airspeed to improve cooling airflow Correct answer.

Explanation

Enriching the mixture lowers combustion temperature and increasing airspeed improves cooling airflow over the cylinders. Together they reduce CHT without sacrificing the climb, whereas leaning or slowing the aircraft worsens the situation.

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

During a descent with the throttle at idle, the EGT indication falls unusually low and the engine begins to run rough. Which cause is most probable?

  1. The oil pressure relief valve has stuck open
  2. Carburetor icing has formed at the throttle plate in the reduced airflow Correct answer.
  3. The magnetos have both failed simultaneously
  4. The propeller governor has failed in the high-pitch position

Explanation

At low power with the throttle nearly closed, the pressure drop and cooling at the throttle plate create favorable conditions for carburetor ice, which causes rough running and a drop in EGT. Applying carburetor heat is the appropriate response.

Question 49Aircraft General Knowledge (Airframe, Systems, Powerplant, Instruments)

Why does an aircraft engine's fuel system typically include both an engine-driven pump and an electric boost pump?

  1. The two pumps operate in series to double the fuel pressure at all times
  2. The engine-driven pump is used only on the ground and the boost pump in flight
  3. The boost pump provides redundancy and prevents vapor lock during critical phases such as takeoff and climb Correct answer.
  4. The boost pump is used to increase the octane rating of the fuel

Explanation

The engine-driven pump supplies fuel in normal operation, while the electric boost pump provides backup pressure and helps suppress vapor lock when fuel is hot or altitude is high. It is normally selected on for takeoff, landing, and when switching tanks.

Question 50Aircraft General Knowledge (Airframe, Systems, Powerplant, Instruments)

In a light aircraft, what is the primary purpose of the dihedral angle built into the wings?

  1. To provide a rolling moment that tends to restore the aircraft to wings-level after a disturbance Correct answer.
  2. To increase the maximum lift coefficient available for landing
  3. To increase the rate at which the aircraft can be trimmed nose-down
  4. To reduce the structural bending moment at the wing root

Explanation

Dihedral is the upward angle of the wings from root to tip. If the aircraft is disturbed and one wing drops, the lower wing meets the relative airflow at a greater angle of attack and produces more lift than the raised wing, generating a restoring roll moment. This is a static lateral stability feature, not a lift or structural-strength device.