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JCAA PPL Theory study materials
JCAA PPL Theory study resources

JCAA PPL Theory practice questions

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Question 1Air Law and JCAA Procedures

Under JCAA rules, when is a pilot required to carry the aircraft's certificate of airworthiness on board during flight?

  1. Only when the aircraft is operated under instrument flight rules
  2. Only when flying outside Japanese territorial airspace
  3. Only when carrying passengers for remuneration
  4. On every flight, including local training flights Correct answer.

Explanation

Japanese air law requires the certificate of airworthiness, certificate of registration and the pilot's licence to be on board for every flight. There is no exemption for local training or private operations. Failure to carry them is an offence even if the documents exist elsewhere.

Question 2Air Law and JCAA Procedures

What is the validity period of a Class 1 aviation medical certificate issued to a private pilot applicant aged 40 or over in Japan?

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

Explanation

JCAA medical certification aligns validity with the pilot's age and the class of certificate. For a private pilot aged 40 or above, the Class 1 certificate is valid for 12 months. Shorter periods apply to commercial operations and to older age bands.

Question 3Air Law and JCAA Procedures

A pilot intends to operate a flight under visual flight rules in controlled airspace at 2,500 ft AME. Which minimum flight visibility applies in class D airspace under Japanese rules?

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

Explanation

In controlled airspace below 3,050 m (10,000 ft) AMSL, VFR flight requires a flight visibility of at least 5,000 m and cloud separation of 150 m vertically and 300 m horizontally. The 5,000 m figure distinguishes controlled from uncontrolled airspace at low level.

Question 4Air Law and JCAA Procedures

What is the standard semicircular cruising level for a magnetic track between 000° and 179° at a pressure altitude above 2,900 ft but below 8,850 ft?

  1. Odd thousands plus 500 ft Correct answer.
  2. Odd thousands only
  3. Even thousands plus 500 ft
  4. Even thousands only

Explanation

Japan applies the ICAO semicircular rule: tracks from 000° to 179° use odd thousands plus 500 ft, while tracks from 180° to 359° use even thousands plus 500 ft. The 500 ft offset applies to levels below 8,850 ft in this band. Above that, the offset is dropped and whole thousands are used.

Question 5Air Law and JCAA Procedures

Which body issues airworthiness directives that are mandatory for Japanese-registered aircraft?

  1. The airport operator
  2. The insurance underwriter
  3. The aircraft manufacturer alone
  4. The JCAA (Civil Aviation Bureau) Correct answer.

Explanation

Airworthiness directives become mandatory for Japanese-registered aircraft when issued or adopted by the Civil Aviation Bureau of the JCAA. Manufacturers publish service bulletins, but only the authority can make compliance legally compulsory. Operators must record compliance in the aircraft logbooks.

Question 6Air Law and JCAA Procedures

A pilot's licence has been lost. What is the correct course of action before the next flight?

  1. Wait 30 days, after which the original is automatically reissued
  2. Fly as normal and carry a photocopy of the lost licence
  3. Ask the flight instructor to certify the pilot's identity in the journey log
  4. Obtain a replacement licence or temporary document from the JCAA before flying Correct answer.

Explanation

A pilot must hold and carry a valid licence for every flight. If it is lost, a replacement or temporary authorisation must be obtained from the JCAA before acting as pilot in command. A photocopy has no legal standing.

Question 7Air Law and JCAA Procedures

What does a flashing red light directed at an aircraft in flight signify?

  1. Aerodrome unsafe, do not land Correct answer.
  2. Give way and continue circling
  3. Cleared to land
  4. Return to the starting point on the aerodrome

Explanation

A flashing red signal to an aircraft in flight means the aerodrome is unsafe and landing is prohibited. It is distinct from a steady red, which means give way and continue circling. Pilots must acknowledge signals and act accordingly.

Question 8Air Law and JCAA Procedures

An aircraft on the ground receives a flashing white light from the tower. What action is required?

  1. Take off immediately
  2. Stop immediately
  3. Taxi clear of the landing area in use
  4. Return to the starting point on the aerodrome Correct answer.

Explanation

For an aircraft on the ground, a flashing white light directs the pilot to return to the starting point on the aerodrome. It is used, for example, when a taxi clearance is cancelled. Steady red requires stopping, and flashing red requires taxiing clear of the landing area.

Question 9Air Law and JCAA Procedures

During a flight, an aircraft experiences a radio communication failure in VMC. What is the appropriate initial action?

  1. Squawk 7600 and continue to the original destination regardless of weather
  2. Climb to the highest available level and hold until fuel is exhausted
  3. Continue under VFR, land at the nearest suitable aerodrome and report arrival Correct answer.
  4. Descend immediately below 500 ft and follow the nearest road

Explanation

In visual meteorological conditions the pilot should continue under VFR, land at the nearest suitable aerodrome and notify the appropriate unit of arrival. Squawking 7600 aids identification, but the priority is a safe landing and reporting. Instrument procedures apply only when VMC cannot be maintained.

Question 10Air Law and JCAA Procedures

What is the purpose of a clearance delivery frequency at a controlled aerodrome?

  1. To coordinate ground vehicle movements on the apron
  2. To provide weather briefings to departing aircraft
  3. To handle emergency communications only
  4. To issue ATC clearances before engine start and taxi Correct answer.

Explanation

Clearance delivery issues route and departure clearances before start-up so that the ground and tower frequencies are not congested. It does not control movement on the manoeuvring area. Read-back of the clearance is required.

Question 11Air Law and JCAA Procedures

A pilot reads back a taxi clearance incorrectly. What must the controller do?

  1. Record the error and report it after landing
  2. Cancel the clearance and instruct the aircraft to shut down
  3. Immediately transmit the correct clearance and require a further read-back Correct answer.
  4. Ignore the error if the aircraft begins to move correctly

Explanation

Controllers must ensure that read-back errors are corrected before the aircraft proceeds. The correct clearance is re-transmitted and a fresh read-back obtained. This safeguards against runway incursions and wrong-route taxiing.

Question 12Air Law and JCAA Procedures

What does the abbreviation ATIS stand for in aeronautical communications?

  1. Automatic Terminal Information Service Correct answer.
  2. Approach and Terminal Instrument Service
  3. Aerodrome Traffic Instruction System
  4. Air Traffic Information Service

Explanation

ATIS is the Automatic Terminal Information Service, a continuous broadcast of recorded non-control information such as weather, runway in use and approach aids. Pilots include the current ATIS code letter when making initial contact.

Question 13Air Law and JCAA Procedures

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

  1. The aircraft being overtaken Correct answer.
  2. The aircraft on the right
  3. The faster aircraft
  4. The aircraft at the lower altitude

Explanation

The aircraft being overtaken has the right of way, and the overtaking aircraft must keep clear by altering heading to the right. This rule applies regardless of aircraft type or speed. It prevents converging flight paths during the overtaking manoeuvre.

Question 14Air Law and JCAA Procedures

Two aircraft are approaching head-on at the same level. What action must each pilot take?

  1. The lower aircraft climbs and the higher descends
  2. The aircraft with the higher performance category maintains heading
  3. Both alter heading to the left
  4. Both alter heading to the right Correct answer.

Explanation

When two aircraft are approaching head-on or nearly so and there is risk of collision, each must alter heading to the right. This creates a predictable separation. Neither aircraft may rely on the other to give way.

Question 15Air Law and JCAA Procedures

An aircraft is landing and another is on the ground taxiing. Which has priority?

  1. The taxiing aircraft, because it is already on the manoeuvring area
  2. The landing aircraft Correct answer.
  3. The aircraft with the shorter remaining taxi distance
  4. Neither; the tower decides case by case with no default rule

Explanation

An aircraft in the final stages of landing has priority over aircraft taxiing on the ground. The taxiing aircraft must hold short and keep clear of the runway. This prevents conflicts at the runway holding point.

Question 16Air Law and JCAA Procedures

What is the minimum horizontal distance an aircraft should keep from other aircraft when taxiing under its own power on an apron?

  1. 25 m
  2. 3 m
  3. 50 m
  4. 10 m Correct answer.

Explanation

Aircraft taxiing under their own power must keep a safe separation, generally about 10 m, from other aircraft and obstacles to allow for wingtip clearance and jet blast. Greater distances may be specified on stands with large aircraft. The tower or marshaller may impose additional restrictions.

Question 17Air Law and JCAA Procedures

When must a pilot report position to ATC without a specific request?

  1. When compelled by the applicable procedures, such as entering a mandatory reporting point Correct answer.
  2. Only when flying above 10,000 ft
  3. At every waypoint regardless of instruction
  4. Only when the transponder fails

Explanation

Position reports are required at compulsory reporting points and whenever directed by ATC or prescribed procedures, not at every waypoint. Unnecessary reports congest the frequency. Pilots should follow the reporting requirements for the airspace and flight rules in use.

Question 18Air Law and JCAA Procedures

What is the meaning of the phrase 'line up and wait' when issued to an aircraft at a controlled aerodrome?

  1. Hold short of the runway and contact ground control
  2. Enter the runway and await take-off clearance without delay
  3. Take off immediately without further clearance
  4. Enter the runway, position for take-off and hold Correct answer.

Explanation

'Line up and wait' authorises the aircraft to enter the runway and position for departure but not to begin the take-off roll. A separate take-off clearance is required. The instruction is acknowledged by read-back of the runway designator.

Question 19Air Law and JCAA Procedures

An aircraft is cleared to land on runway 16. What does the number 16 indicate?

  1. The magnetic heading of the runway is approximately 160° Correct answer.
  2. The runway is 1,600 m long
  3. The runway is the 16th at the aerodrome
  4. The runway elevation is 16 ft

Explanation

Runway designators express the magnetic heading of the runway in whole tens of degrees, rounded. The number 16 therefore corresponds to approximately 160°. The reciprocal end would be numbered 34.

Question 20Air Law and JCAA Procedures

What action should a pilot take on receiving a TCAS resolution advisory while in IMC under radar control?

  1. Reduce speed only and maintain altitude
  2. Follow the resolution advisory immediately and notify ATC Correct answer.
  3. Turn off the TCAS to avoid conflicting instructions
  4. Ignore it because ATC has already provided separation

Explanation

A resolution advisory must be followed immediately, even when under radar control, because it responds to an actual traffic threat. The pilot then informs ATC of the deviation. ATC separation does not override the advisory.

Question 21Air Law and JCAA Procedures

What is the significance of a red and white striped marker board at an aerodrome?

  1. It marks the boundary of the apron
  2. It indicates an obstacle or unserviceable area to be avoided Correct answer.
  3. It identifies the touchdown zone of the secondary runway
  4. It marks the aiming point of the runway

Explanation

Red and white striped markers denote obstacles or unserviceable areas on or near the movement area. Pilots must avoid them and not treat them as guidance. They are distinct from runway markings, which are white.

Question 22Air Law and JCAA Procedures

An aircraft is entering Japanese territorial airspace on a flight from abroad. What is the general requirement regarding flight plans?

  1. A flight plan is required only for IFR flights
  2. A flight plan may be filed after landing
  3. A flight plan must be filed and activated before entry Correct answer.
  4. No flight plan is required if the flight remains VFR

Explanation

Flights entering or leaving Japanese territory must file a flight plan in advance and activate it at the boundary. This allows the authorities to maintain traffic and border awareness. Post-flight filing defeats the purpose of the requirement.

Question 23Air Law and JCAA Procedures

What is the standard emergency frequency monitored for distress communications in Japanese airspace?

  1. 243.0 MHz
  2. 123.45 MHz
  3. 118.0 MHz
  4. 121.5 MHz Correct answer.

Explanation

121.5 MHz is the international VHF emergency frequency monitored for distress and urgency communications. 243.0 MHz is the corresponding military UHF frequency. 123.45 MHz is used for air-to-air communications, not distress.

Question 24Air Law and JCAA Procedures

A pilot becomes aware of fatigue before a planned flight. Under JCAA regulations, what is the correct decision?

  1. Fly if the aircraft is equipped with an autopilot
  2. Do not act as a flight crew member while unfit due to fatigue Correct answer.
  3. Fly only if accompanied by another pilot
  4. Fly if the flight is short and the weather is good

Explanation

Flight crew members must not perform duties while unfit due to fatigue, illness, medication or alcohol. Fatigue impairs judgement and reaction time in ways the pilot may not detect. The flight should be postponed or another crew member substituted.

Question 25Air Law and JCAA Procedures

What is the requirement for a pilot regarding alcohol consumption before acting as a flight crew member in Japan?

  1. No alcohol within 8 hours of duty and a blood alcohol content below 0.3 mg/ml Correct answer.
  2. No alcohol within 24 hours of duty regardless of quantity
  3. Alcohol is permitted if the pilot feels unaffected
  4. Only a breath test result below 0.5 mg/l is required

Explanation

Japanese rules prohibit alcohol consumption within 8 hours of duty and require blood alcohol content below 0.3 mg/ml at the time of duty. Both the time limit and the concentration limit must be satisfied. The limits apply to all flight crew.

Question 26Air Law and JCAA Procedures

Under Japanese aviation regulations, what is the validity period of a Class 1 aviation medical certificate issued to a private pilot under the age of 40?

  1. Two years from the date of examination
  2. One year from the date of examination
  3. Three years from the date of examination Correct answer.
  4. Five years from the date of examination

Explanation

JCAA medical certification rules set the validity of a Class 1 certificate by age band: for a holder under 40 years of age the certificate remains valid for three years, and for a holder aged 40 or over the validity shortens to one year. The validity is counted from the date of the medical examination, not the date the licence is issued.

Question 27Air Law and JCAA Procedures

A pilot holds a Japanese private pilot licence for aeroplanes and wishes to act as pilot-in-command carrying passengers at night. Which additional qualification is required?

  1. A total of 200 hours of cross-country flight time
  2. A night flight training endorsement recorded in the pilot logbook Correct answer.
  3. A Class 1 medical certificate in place of the Class 2
  4. An instrument rating issued by the JCAA

Explanation

A private pilot may not carry passengers at night until night flight training has been completed and the endorsement is entered, confirming the pilot has met the JCAA night experience and training requirements. The endorsement is recorded in the pilot's logbook and is separate from an instrument rating.

Question 28Air Law and JCAA Procedures

What is the standard squawk code that a pilot must select when experiencing a radio communication failure in Japanese airspace?

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

Explanation

The three special SSR codes are standardised internationally: 7500 for unlawful interference, 7600 for radio communication failure, and 7700 for a general emergency. A pilot who loses two-way radio communication sets 7600 so that ATC and other aircraft can identify the situation.

Question 29Air Law and JCAA Procedures

An aircraft is being flown VFR in controlled airspace and encounters deteriorating weather. Which statement correctly describes the pilot's obligation under the JCAA rules on VFR flight?

  1. The pilot may descend below the VMC minima if the surface is in sight
  2. The pilot must obtain an IFR clearance or leave controlled airspace before the VMC minima are lost Correct answer.
  3. The pilot must request a special VFR clearance and continue at the same level
  4. The pilot may continue VFR as long as the aircraft remains clear of cloud

Explanation

A VFR flight must remain within the prescribed visibility and cloud separation minima at all times. If conditions deteriorate so that VMC can no longer be maintained, the pilot must either obtain an IFR clearance (if suitably rated and equipped) or leave controlled airspace before the minima are lost.

Question 30Air Law and JCAA Procedures

What is the meaning of a continuous green light signal directed at an aircraft on the ground?

  1. Cleared to taxi Correct answer.
  2. Stop
  3. Return to starting point on the aerodrome
  4. Cleared for take-off

Explanation

In the standard light-signal table, a steady green light directed at an aircraft on the ground means it is cleared to taxi, while the same signal to an aircraft in flight means cleared to land. The signals are used when radio communication is unavailable.

Question 31Air Law and JCAA Procedures

Which document must a pilot-in-command ensure is on board an aircraft before flight, in addition to the certificate of airworthiness and the pilot's licence?

  1. The airworthiness review staff training record
  2. The aircraft flight manual and the certificate of registration Correct answer.
  3. The operator's marketing brochure
  4. The maintenance organisation's internal audit report

Explanation

The documents that must be carried on board include the certificate of registration, the certificate of airworthiness, the aircraft flight manual (or equivalent document), and the licences of the flight crew. These establish the aircraft's identity, airworthiness and operating limitations.

Question 32Air Law and JCAA Procedures

A pilot on a VFR flight in class C airspace wishes to change altitude. What is the correct procedure?

  1. Change altitude after squawking 7000 and turning off the transponder
  2. Change altitude after advising other traffic on the common frequency
  3. Change altitude only after obtaining an ATC clearance Correct answer.
  4. Change altitude freely because VFR flights are not separated from IFR

Explanation

In class C airspace all flights are subject to ATC clearance, and a VFR flight may not change level without a specific clearance. The controller provides separation between IFR and VFR traffic, so an unannounced level change would compromise that separation.

Question 33Air Law and JCAA Procedures

What does a white cross marking displayed in a signal square at an aerodrome indicate to a pilot?

  1. The runway in use has changed Correct answer.
  2. Glider flying is in progress
  3. The aerodrome is closed to all traffic
  4. Take-off and landing are to be conducted on the runway only

Explanation

A white cross in the signal square indicates that the runway in use has been changed and that take-off and landing should be carried out in the new direction. Pilots should confirm the current runway in use by radio or by observing the landing direction indicator.

Question 34Air Law and JCAA Procedures

An aircraft is approaching to land and observes a horizontal white bar alongside a red bar in the visual approach slope indicator. What does this indicate?

  1. The aircraft is above the approach slope Correct answer.
  2. The aircraft is below the approach slope
  3. The aircraft is on the correct approach slope
  4. The approach slope indicator is unserviceable

Explanation

In a two-bar VASI system, white over red means the aircraft is above the approach slope, red over white means below, and red over red means on the correct slope. The pilot should adjust the rate of descent to regain the correct glide path.

Question 35Air Law and JCAA Procedures

What is the purpose of the JCAA's requirement for a flight plan to be submitted before a flight into controlled airspace under IFR?

  1. To calculate the landing fees in advance
  2. To allow ATC to provide separation and search and rescue coordination Correct answer.
  3. To register the flight with the aerodrome operator
  4. To satisfy the aircraft insurance policy

Explanation

A flight plan gives ATC the information needed to provide separation and to initiate search and rescue if the aircraft fails to arrive. It also allows the flow of traffic to be coordinated before departure.

Question 36Air Law and JCAA Procedures

A pilot is planning a flight and the destination aerodrome has no published instrument approach and the weather is forecast to be marginal. Which action best reflects the JCAA requirement for fuel planning?

  1. Carry fuel sufficient to reach the destination and no more
  2. Carry fuel for the route, an alternate, and the required reserve Correct answer.
  3. Carry fuel for the planned route only, plus 10 minutes
  4. Carry fuel for the route plus the holding time at destination

Explanation

Fuel planning must include fuel to the destination, fuel to a suitable alternate where one is required, and the prescribed reserve. When weather is marginal, the alternate and reserve become critical because a diversion may be necessary.

Question 37Air Law and JCAA Procedures

An aircraft is involved in an accident that causes serious injury to a person on board. Which reporting obligation applies to the pilot-in-command under JCAA rules?

  1. Report the accident to the JCAA without delay by the quickest available means Correct answer.
  2. Report the accident only in the annual return at the end of the year
  3. Report the accident only if the aircraft is damaged beyond repair
  4. Report the accident only if another aircraft is involved

Explanation

An accident involving serious injury or substantial damage must be notified to the JCAA immediately by the quickest available means, followed by a written report. Prompt notification allows the authorities to begin investigation and to take safety action.

Question 38Air Law and JCAA Procedures

What does the abbreviation 'AFTN' refer to in the context of Japanese civil aviation communications?

  1. The aerodrome fire training network
  2. The automatic flight terrain notification system
  3. The air traffic flow notification system
  4. The aeronautical fixed telecommunication network used for flight and safety messages Correct answer.

Explanation

AFTN is the aeronautical fixed telecommunication network, a worldwide ground-based network used to exchange flight plans, meteorological data and other operational messages between aviation units. It is distinct from air-ground radio communication.

Question 39Air Law and JCAA Procedures

A pilot receives an ATC instruction that cannot be complied with safely. What is the correct response?

  1. Advise ATC immediately that the instruction cannot be complied with and state the reason Correct answer.
  2. Read back the instruction and comply as cleared
  3. Ignore the instruction and continue on the current clearance
  4. Comply first and report the problem after landing

Explanation

If a clearance or instruction cannot be accepted or complied with, the pilot must inform ATC immediately and explain the reason, so that the controller can issue an alternative. Silently ignoring an instruction or complying when it is unsafe both endanger separation.

Question 40Air Law and JCAA Procedures

Under JCAA rules, what is the maximum permitted blood alcohol concentration for a person acting as a flight crew member?

  1. 0.00 percent Correct answer.
  2. 0.03 percent
  3. 0.08 percent
  4. 0.05 percent

Explanation

Japanese aviation law prohibits flight crew from performing duties with any alcohol in the body; the limit is effectively zero, and flight crew must not act if they have consumed alcohol within the prescribed period before flight. This is stricter than many other jurisdictions.

Question 41Aircraft General Knowledge

In a four-stroke aircraft piston engine, which stroke immediately follows the power (combustion) stroke?

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

Explanation

The four-stroke cycle runs induction, compression, power, then exhaust. After the burning mixture has driven the piston down on the power stroke, the exhaust valve opens and the piston rises to push the spent gases out. The next cycle then begins with a fresh intake stroke.

Question 42Aircraft General Knowledge

What is the primary function of the carburettor heat control in a piston engine?

  1. To warm the engine oil during start in cold weather
  2. To raise the fuel temperature before it reaches the injectors
  3. To supply warmed air to the induction system to prevent or clear carburettor icing Correct answer.
  4. To heat the cabin air supply for occupant comfort

Explanation

Carburettor heat ducts air over an exhaust-heated muff around the carburettor. This raises the air temperature and melts or prevents ice forming at the venturi and throttle butterfly, where cooling and fuel vaporisation can freeze moisture. It is an anti-icing control, not a cabin or oil heater.

Question 43Aircraft General Knowledge

A pilot notices that during a climb the oil temperature rises steadily while oil pressure remains normal. Which action is the most appropriate first response?

  1. Continue the climb unchanged; oil temperature always stabilises on its own
  2. Switch off the engine immediately to prevent damage
  3. Increase the climb rate to improve cooling through the cowl
  4. Reduce the climb angle or level off briefly to increase airflow and lower the temperature Correct answer.

Explanation

A prolonged steep climb at low airspeed reduces cooling airflow through the cowling, so oil temperature climbs. Reducing the climb angle or levelling off restores airflow and lets the temperature fall back into the green arc. Normal pressure indicates the oil system is still functioning, so shutting down is not warranted.

Question 44Aircraft General Knowledge

Why does a fixed-pitch propeller have a lower efficiency at high true airspeed?

  1. The blade angle is fixed, so the angle of attack of the blades becomes too small at high speed Correct answer.
  2. The propeller diameter increases with speed
  3. The blades stall at high rotational speed
  4. The engine cannot produce enough power at high altitude

Explanation

A fixed-pitch propeller is optimised for one combination of speed and rpm. As true airspeed rises, the relative airflow meets the blade at a smaller angle of attack, so thrust and efficiency fall. A constant-speed propeller can increase blade angle to keep the angle of attack near optimum.

Question 45Aircraft General Knowledge

Which statement correctly describes the purpose of the magneto in an aircraft ignition system?

  1. It regulates the charging rate of the battery
  2. It generates its own high-tension current to fire the spark plugs independently of the aircraft battery Correct answer.
  3. It converts AC from the alternator into DC for the electrical bus
  4. It provides the low-voltage signal to the starter solenoid

Explanation

A magneto is a self-contained generator driven by the engine that produces high voltage for the spark plugs. Because it does not depend on the aircraft battery, ignition continues even if the electrical system fails. This independence is why magnetos are used rather than battery-fed coil ignition.

Question 46Aircraft General Knowledge

Before flight, a pilot selects each magneto in turn during the run-up check and observes the rpm drop. What is the purpose of this check?

  1. To verify the alternator is charging the battery
  2. To set the idle mixture for the take-off
  3. To test the operation of the vacuum pump
  4. To confirm both magnetos and their associated spark plug circuits are functioning correctly Correct answer.

Explanation

Switching to each magneto alone should produce a small, similar rpm drop because only one set of plugs is then firing. A large drop, no drop, or rough running indicates a faulty magneto, plug or lead. Comparing the two drops confirms both ignition circuits are serviceable.

Question 47Aircraft General Knowledge

In a normally aspirated piston engine, what happens to maximum available power as altitude increases?

  1. It remains constant because the throttle is fully open
  2. It decreases because the density of the inducted air falls Correct answer.
  3. It decreases only above the tropopause
  4. It increases because the air is colder at altitude

Explanation

Power depends on the mass of air and fuel drawn into the cylinders. As altitude rises, air density falls, so each intake stroke takes in less oxygen and less fuel can be burned. Maximum power therefore decreases steadily with altitude until a turbocharger or supercharger is used.

Question 48Aircraft General Knowledge

What does the manifold pressure gauge indicate on a normally aspirated engine?

  1. The absolute pressure of the air/fuel mixture in the induction manifold Correct answer.
  2. The pressure inside the cylinders during combustion
  3. The pressure of the oil leaving the pump
  4. The differential pressure across the fuel filter

Explanation

The manifold pressure gauge reads absolute pressure in the induction system, usually in inches of mercury. With the engine stopped it reads ambient pressure, and it falls below ambient as the throttle closes and the engine pumps air out of the manifold. It is a direct indicator of power being developed.

Question 49Aircraft General Knowledge

During a descent with the throttle closed, the manifold pressure gauge in a normally aspirated engine will read:

  1. Above ambient pressure, because of ram air effect
  2. Exactly ambient pressure at all times
  3. Below ambient pressure, because the engine is pumping air out of the manifold Correct answer.
  4. Zero whenever the engine is running

Explanation

With the throttle closed the engine acts as a pump, drawing air out of the manifold faster than it can enter. The result is a manifold pressure well below ambient, which is why the gauge is used to avoid over-stressing the engine when the throttle is reopened.

Question 50Aircraft General Knowledge

What is the main purpose of the engine air filter (airbox filter) on a light aircraft?

  1. To separate water from the fuel supply
  2. To prevent dust and foreign matter entering the induction system and wearing the engine Correct answer.
  3. To cool the induction air before it reaches the cylinders
  4. To silence the exhaust noise

Explanation

The filter traps dust, sand and other particles that would otherwise be drawn into the cylinders and cause abrasive wear. Many installations include an alternate air door that bypasses a blocked filter so the engine can still breathe. Filtration protects the engine, it does not cool or silence it.