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AAI JE ATC practice questions

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Question 1Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

In air traffic control phraseology, what does the instruction "LINE UP AND WAIT" authorise an aircraft to do?

  1. Hold short of the runway at the CAT I holding position
  2. Backtrack the runway to the holding point
  3. Enter the runway and hold in position, but not begin the take-off roll Correct answer.
  4. Begin the take-off roll immediately without further clearance

Explanation

Line up and wait permits the aircraft to enter the runway and position itself for departure while awaiting take-off clearance. It explicitly does not authorise commencing the take-off roll, which requires a separate take-off clearance.

Question 2Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

An aircraft is cleared to "descend to FL 150". Which statement correctly describes the clearance limit?

  1. The clearance applies only after the aircraft passes the next waypoint
  2. The aircraft must not descend below FL 150 without a further clearance Correct answer.
  3. The aircraft must level at FL 150 for at least five minutes before continuing
  4. The aircraft may descend below FL 150 if the crew considers it necessary

Explanation

A clearance to a level is a limit: the aircraft may descend to that level but must not go below it until further cleared. Descent below the cleared level without a new clearance is a level bust.

Question 3Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

What is the primary purpose of secondary surveillance radar (SSR) in an air navigation service?

  1. To obtain identity and pressure altitude by interrogating the aircraft transponder Correct answer.
  2. To detect aircraft by skin-paint reflection from the fuselage
  3. To measure aircraft ground speed by Doppler shift alone
  4. To provide terrain mapping for the controller's display

Explanation

SSR relies on a transponder reply to interrogations, giving identity (Mode A/squawk) and pressure altitude (Mode C) in addition to range and azimuth. Primary radar instead depends on skin-paint reflections.

Question 4Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

In the ICAO wake turbulence categories, an aircraft with a maximum certificated take-off mass of 136 000 kg falls into which category?

  1. Medium
  2. Light
  3. Heavy Correct answer.
  4. Super

Explanation

The Heavy category covers aircraft with a maximum certificated take-off mass of 136 000 kg or more, up to but excluding the 560 000 kg A380-type threshold. A 136 000 kg aircraft therefore sits exactly at the Heavy boundary.

Question 5Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

What does a QNH altimeter setting cause an altimeter to indicate when the aircraft is on the ground at the reference station?

  1. Height above the aerodrome
  2. True altitude above mean sea level at all times
  3. Elevation of the aerodrome Correct answer.
  4. Flight level referenced to 1013.2 hPa

Explanation

With QNH set, the altimeter reads aerodrome elevation when the aircraft is on the ground at that station. It approximates altitude above mean sea level in flight but is not a true altitude because of temperature and pressure errors.

Question 6Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

On an aerodrome, which marking identifies a displaced threshold?

  1. A row of white arrowheads across the runway width Correct answer.
  2. A series of white longitudinal stripes at the runway end
  3. A red and white checkerboard at the runway centre
  4. A yellow chevron pattern on the shoulders

Explanation

A displaced threshold is marked by a row of white arrowheads (piano keys pointing toward the threshold) across the runway, with the area before it unavailable for landing. The runway end itself is normally marked by threshold stripes.

Question 7Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

What is the function of the ATC transponder code 7700?

  1. Radio communication failure
  2. General emergency Correct answer.
  3. Unlawful interference
  4. Lost communication with the ground station

Explanation

Code 7700 is the general emergency squawk, alerting ATC that the aircraft is in distress. Codes 7600 and 7500 are reserved for radio failure and unlawful interference respectively.

Question 8Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

In a standard instrument departure, what does a "climb gradient" expressed as a percentage represent?

  1. The ratio of vertical speed to ground speed
  2. The angle between the flight path and the horizon in degrees
  3. The rate of climb required to reach cruise level by a fixed point
  4. The ratio of vertical distance gained to horizontal distance travelled Correct answer.

Explanation

A climb gradient in percent is the vertical distance gained divided by the horizontal distance travelled, multiplied by 100. It differs from a climb angle in degrees and from a rate of climb, which depends on ground speed.

Question 9Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

An aircraft is instructed to hold at a VOR over a fix with a right-hand holding pattern. Inbound to the fix on the 090° radial, what is the outbound heading of the holding pattern?

  1. 270° Correct answer.
  2. 180°
  3. 360°
  4. 090°

Explanation

Inbound on the 090° radial means tracking toward the station on a heading of 270°. A right-hand pattern turns the aircraft to the right, so the outbound leg is flown on the reciprocal of 270°, which is 090° radial outbound, i.e. heading 090° outbound from the fix, giving the outbound heading of 270° when corrected.

Question 10Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

Two aircraft are on converging courses at the same level. Which rule applies under the standard right-of-way conventions?

  1. Both aircraft turn right simultaneously
  2. The aircraft on the left gives way to the aircraft on the right Correct answer.
  3. The aircraft with the higher category gives way
  4. The faster aircraft gives way to the slower aircraft

Explanation

When two aircraft converge at approximately the same level, the aircraft that has the other on its right must give way. This is the standard right-of-way rule for converging traffic.

Question 11Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

A controller issues a clearance with the instruction "DESCEND AT 1500 FEET PER MINUTE OR GREATER". What does this instruction require?

  1. A descent to be completed within a fixed time
  2. A descent only when the aircraft is above FL 150
  3. A minimum rate of descent of 1500 ft/min until further advised Correct answer.
  4. A maximum rate of descent of 1500 ft/min

Explanation

The phrase specifies a minimum rate of descent: the aircraft must descend at 1500 ft/min or more. It is used when a rapid descent is needed for separation or traffic management.

Question 12Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

An aircraft is cleared for an ILS approach to runway 27. The localizer provides guidance in which plane?

  1. Distance to the threshold
  2. Glidepath angle information
  3. Vertical guidance to the touchdown point
  4. Lateral guidance to the runway centreline Correct answer.

Explanation

The localizer transmits lateral guidance aligned with the runway centreline, allowing the aircraft to track the extended centreline. Vertical guidance is provided by the glidepath component.

Question 13Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

What is the purpose of a radar separation minimum of 5 NM between two aircraft in the same airspace?

  1. To ensure wake turbulence avoidance only
  2. To allow controllers to reduce separation in terminal areas
  3. To guarantee vertical separation of 1000 ft
  4. To provide a standard lateral or longitudinal separation buffer under surveillance Correct answer.

Explanation

A 5 NM radar separation minimum provides a standard buffer between identified aircraft under surveillance in the relevant airspace. It is a horizontal separation standard, distinct from vertical separation and from wake turbulence spacing.

Question 14Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

In the absence of a specific clearance, what does a transponder code of 2000 indicate in many airspace environments?

  1. The aircraft is conducting a test flight
  2. The aircraft is in an emergency
  3. The aircraft is a military flight
  4. The aircraft has not received a specific code assignment Correct answer.

Explanation

Code 2000 is commonly used to indicate that an aircraft has not been assigned a specific discrete code, often in areas where code allocation is not required. It is distinct from emergency and special-purpose codes.

Question 15Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

What does the term "ATIS" refer to in air traffic services?

  1. A continuous broadcast of recorded aerodrome and meteorological information Correct answer.
  2. An approach lighting system
  3. A discrete code allocation system
  4. A radar handover procedure between adjacent sectors

Explanation

ATIS is a continuous, recorded broadcast providing current aerodrome information such as weather, runway in use, and operational data. Pilots use it to reduce voice communication workload.

Question 16Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

An aircraft reports "established on the localizer" during an ILS approach. What does this confirm?

  1. The aircraft is cleared to land
  2. The aircraft is aligned with the runway centreline laterally Correct answer.
  3. The aircraft is tracking the glidepath
  4. The aircraft has passed the outer marker

Explanation

Being established on the localizer confirms lateral alignment with the runway centreline. It does not confirm glidepath interception, marker passage, or landing clearance.

Question 17Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

In a standard holding pattern, what is the standard inbound leg timing for an aircraft holding at or below 14 000 ft?

  1. Three minutes
  2. Two minutes
  3. One minute Correct answer.
  4. One and a half minutes

Explanation

The standard inbound leg timing is one minute at or below 14 000 ft, with adjustments made for wind. Above 14 000 ft the timing is typically one and a half minutes.

Question 18Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

A runway is described as having a "displaced threshold". What operational consequence does this have for landing aircraft?

  1. The touchdown zone moves beyond the runway end
  2. The take-off run available is also reduced
  3. The runway cannot be used for landing at all
  4. The landing distance available is reduced compared with the full runway length Correct answer.

Explanation

A displaced threshold reduces the landing distance available because the portion before the displaced threshold cannot be used for touchdown. The full runway length may still be available for take-off in some cases.

Question 19Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

What is the principal function of a primary surveillance radar (PSR) in en-route air traffic control?

  1. To detect and display aircraft returns without requiring cooperation from the aircraft Correct answer.
  2. To provide meteorological data only
  3. To relay voice communications
  4. To interrogate transponders for identity

Explanation

PSR detects aircraft by skin-paint reflection of radar energy, so it works without any transponder cooperation. It provides position information but not identity or altitude.

Question 20Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

An aircraft is cleared to cross a runway and then instructed to hold short of the next runway. What is the controller's responsibility regarding the first runway crossing?

  1. To confirm the aircraft has stopped before the first runway
  2. To ensure the aircraft has fully crossed before issuing any further clearance Correct answer.
  3. To verify the aircraft's transponder code
  4. To provide wake turbulence separation only

Explanation

The controller must ensure the aircraft has fully vacated the first runway before issuing a clearance that could conflict with it. Runway incursion prevention requires positive confirmation of crossing completion.

Question 21Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

In reduced vertical separation minimum (RVSM) airspace, what is the standard vertical separation between aircraft at FL 290 and above?

  1. 2000 ft
  2. 3000 ft
  3. 500 ft
  4. 1000 ft Correct answer.

Explanation

RVSM permits 1000 ft vertical separation between aircraft at FL 290 and above, down from the earlier 2000 ft standard. Aircraft must be RVSM-approved to operate in this airspace.

Question 22Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

A controller observes two aircraft on the same radar track with 3 NM separation in airspace where the minimum is 5 NM. What is the most appropriate immediate action?

  1. Issue a safety alert and take action to restore the required separation Correct answer.
  2. Transfer control to the adjacent sector
  3. Reduce the separation minimum to 3 NM
  4. Wait for the aircraft to increase separation naturally

Explanation

When separation is below the minimum, the controller must issue a safety alert and take immediate action to restore the required separation. Waiting or transferring control risks a loss of separation.

Question 23Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

An aircraft on an ILS approach reports "glidepath intercept" but the controller observes it below the published glidepath. What is the most likely consequence and appropriate action?

  1. The aircraft may descend below the obstacle clearance surface; issue a safety alert and consider a go-around Correct answer.
  2. The transponder will lose altitude reporting
  3. The localizer will fail; switch to a visual approach
  4. The aircraft will land long; no action is required

Explanation

Being below the glidepath reduces obstacle clearance and may bring the aircraft below the protected surface. The controller should issue a safety alert and be prepared to instruct a go-around.

Question 24Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

In a holding pattern with a strong tailwind on the inbound leg, what adjustment should the pilot make to remain within the protected airspace?

  1. Increase the outbound leg time to compensate for the tailwind
  2. Fly the outbound leg at a higher speed
  3. Decrease the outbound leg time and adjust the inbound timing Correct answer.
  4. Ignore wind and fly standard timings

Explanation

With a tailwind on the inbound leg, the aircraft covers ground faster, so the outbound leg time should be reduced to keep the pattern within protected airspace. Inbound timing is adjusted to account for wind drift.

Question 25Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

Why does a secondary surveillance radar system require a pressure altitude reference of 1013.2 hPa for Mode C reporting?

  1. To provide terrain clearance information to the controller
  2. To enable the transponder to compute true altitude
  3. To allow altitude comparison between aircraft regardless of local pressure Correct answer.
  4. To satisfy meteorological reporting requirements

Explanation

Mode C altitude is referenced to the standard pressure 1013.2 hPa so that all aircraft report on a common scale, allowing controllers to compare and separate traffic without local pressure variations.

Question 26Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

In air traffic control, what does the abbreviation SSR stand for?

  1. Secondary Surveillance Radar Correct answer.
  2. Sector Surveillance Range
  3. Surface Search Radar
  4. Standard Separation Requirement

Explanation

SSR refers to Secondary Surveillance Radar, a cooperative system in which ground interrogators trigger replies from aircraft transponders. Unlike primary radar, it depends on the aircraft transponder rather than passive skin reflection, which is why it can provide identification and pressure altitude.

Question 27Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

What does the term "squawk ident" instruct a pilot to do?

  1. Report the aircraft's altitude verbally to the controller
  2. Select the emergency code 7700 on the transponder
  3. Change the transponder to standby mode
  4. Activate the transponder IDENT feature to highlight the aircraft on the controller's display Correct answer.

Explanation

The IDENT feature causes a distinctive identification pulse in the transponder reply, which highlights the aircraft return on the controller's situation display. It is used to confirm which radar return corresponds to a specific flight. It does not change the assigned code or the aircraft's altitude reporting.

Question 28Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

Which unit is normally used to express horizontal radar separation between aircraft in en-route airspace?

  1. Nautical miles Correct answer.
  2. Kilometres per hour
  3. Flight levels
  4. Feet

Explanation

Horizontal radar separation is expressed in nautical miles because distance on navigation displays and charts is measured in nautical miles. Vertical separation is expressed in feet or flight levels, and speed in knots or kilometres per hour. Mixing these units would make separation standards ambiguous.

Question 29Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

What is the primary purpose of an ATC clearance?

  1. To guarantee the aircraft will not be delayed
  2. To authorise an aircraft to proceed under specified traffic conditions Correct answer.
  3. To provide the aircraft with the controller's personal flight plan
  4. To transfer responsibility for navigation to the ground station

Explanation

A clearance authorises an aircraft to proceed under conditions specified by the controller, and it is issued for the purpose of providing separation. It is not a guarantee against delay or a transfer of navigation responsibility, which remains with the pilot. The pilot must still comply with instructions and report any inability to do so.

Question 30Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

What does a pilot's readback of an ATC clearance primarily serve to do?

  1. Indicate that the aircraft has started its descent
  2. Confirm that the pilot has correctly understood the instruction Correct answer.
  3. Allow the controller to log the flight's fuel state
  4. Replace the need for further radio communication

Explanation

Readback allows the controller to verify that the crew has correctly received and understood the clearance, catching errors before they affect separation. It is a safety barrier rather than a formality, and controllers must listen for and correct discrepancies. It does not remove the need for subsequent communications.

Question 31Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

In radiotelephony, what does the phrase "say again" mean?

  1. Stand by for further instructions
  2. Cancel your last clearance
  3. Repeat your last transmission Correct answer.
  4. Change to another frequency

Explanation

"Say again" is the standard radiotelephony phrase requesting repetition of all or part of a transmission. It is distinct from "stand by", which means wait, and from "disregard", which cancels a previous transmission. Clear phraseology reduces the risk of misunderstanding on congested frequencies.

Question 32Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

What is the function of a clearance delivery position at a controlled aerodrome?

  1. To issue take-off and landing clearances on the runway
  2. To sequence arrivals onto the final approach path
  3. To provide pre-departure clearances before the aircraft reaches the holding point Correct answer.
  4. To manage ground vehicle movements on the apron

Explanation

Clearance delivery issues route and departure clearances before taxi, reducing workload on ground and tower positions. Take-off and landing clearances remain with the tower controller. Separating these functions improves efficiency at busy aerodromes.

Question 33Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

What does the abbreviation QNH represent in aviation altimetry?

  1. The pressure setting that makes the altimeter read zero at the aerodrome
  2. The altimeter setting that makes the altimeter indicate elevation above mean sea level at the aerodrome Correct answer.
  3. The standard pressure setting used above the transition level
  4. The density altitude at the runway threshold

Explanation

QNH is the pressure setting which, when set on the altimeter subscale, causes the altimeter to indicate elevation above mean sea level at the aerodrome. QFE, by contrast, causes the altimeter to read zero on the aerodrome. QNE corresponds to the standard setting of 1013.2 hPa used above the transition level.

Question 34Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

An aircraft is cleared to descend to 4000 ft with the instruction "report leaving 6000 ft". What does the controller expect the pilot to do?

  1. Report the aircraft's current altitude immediately
  2. Report when the aircraft passes 6000 ft in the descent Correct answer.
  3. Report when the aircraft reaches 4000 ft
  4. Report every 1000 ft during the descent

Explanation

The instruction requires the pilot to transmit a report at the moment the aircraft leaves the specified level of 6000 ft. This gives the controller timely confirmation of the vertical movement. The final cleared level of 4000 ft is separately acknowledged in the readback.

Question 35Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

Two aircraft are established in level flight at the same altitude on routes that cross. What does the controller need to ensure before allowing them to proceed?

  1. That both aircraft have the same transponder code
  2. That both aircraft are on the same radio frequency
  3. That vertical or horizontal separation is maintained at all times Correct answer.
  4. That both aircraft have filed identical flight plans

Explanation

The core responsibility is to ensure that separation, either vertical or horizontal, is maintained throughout the period the aircraft could conflict. Transponder codes, frequencies, and flight plans do not themselves provide separation. Without an established separation standard, the conflict is unresolved.

Question 36Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

A controller needs to pass a long route clearance to a departing aircraft. Which technique best reduces the chance of readback error?

  1. Ask the pilot to copy the clearance after take-off
  2. Omit the route and pass only the initial heading
  3. Pass the clearance in full at a fast rate to save frequency time
  4. Break the clearance into manageable segments and confirm the readback of each Correct answer.

Explanation

Segmenting a clearance allows the pilot to record and read back each part, reducing the chance that a long transmission is misheard or partially missed. Fast delivery of a long clearance increases the risk of error. Full route details should be passed before departure where possible.

Question 37Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

What does the term "estimated time of arrival" (ETA) mean when provided by a flight crew to ATC?

  1. The time the flight plan was filed
  2. The time the aircraft is expected to arrive over a specified point or aerodrome Correct answer.
  3. The time the aircraft will next contact the controller
  4. The time the aircraft will commence its descent

Explanation

ETA is the crew's estimate of the time the aircraft will arrive over a designated point or aerodrome. Controllers use it for planning sequencing and comparing with actual progress. It is distinct from the actual time over the point, which is reported when it occurs.

Question 38Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

An aircraft is instructed to "hold short of runway 09" after landing on runway 27. What does this instruction require?

  1. Continue taxiing across runway 09 without stopping
  2. Return to the runway threshold for a further landing
  3. Vacate the runway onto the nearest taxiway
  4. Stop before entering or crossing runway 09 and await further clearance Correct answer.

Explanation

A hold short instruction requires the aircraft to stop before the specified runway holding position and not proceed until further clearance is given. It protects the runway from unauthorised entry. The crew must read back the instruction and maintain the hold until released.

Question 39Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

A controller observes an aircraft deviating from its assigned heading. What is the most appropriate initial action?

  1. Contact the aircraft to verify its heading and provide correction if needed Correct answer.
  2. Assume the pilot is correcting and take no action
  3. Immediately issue a traffic alert to all aircraft on the frequency
  4. File a report before contacting the aircraft

Explanation

The controller should first establish whether the aircraft is actually off heading and why, then issue the appropriate correction. Assuming correction may allow a developing conflict to go unnoticed. Reporting follows after the situation is resolved and understood.

Question 40Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

What is the purpose of a low-level wind shear alert system at an aerodrome?

  1. To provide the aerodrome QNH for altimeter setting
  2. To measure the braking action on the runway surface
  3. To detect hazardous wind shear near the runway and warn pilots and controllers Correct answer.
  4. To record the number of aircraft movements per hour

Explanation

A low-level wind shear alert system uses sensors around the aerodrome to detect wind shear and provides warnings that can be passed to pilots. Wind shear can cause sudden airspeed changes close to the ground, particularly during approach and departure. Braking action and altimeter settings are separate functions.

Question 41Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

An aircraft on approach reports "going around". What does this indicate to the tower controller?

  1. The aircraft has landed and is vacating the runway
  2. The aircraft has lost radio communication
  3. The aircraft is abandoning the approach and will climb away Correct answer.
  4. The aircraft is requesting a lower approach speed

Explanation

A go-around report indicates that the aircraft is discontinuing its approach and climbing away, often because of an unstable approach or an obstruction on the runway. The controller must then provide instructions and separation for the missed approach. It is not a landing confirmation or a speed request.

Question 42Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

What does the term "blind transmission" mean in air traffic communications?

  1. A transmission made by a ground station only
  2. A transmission encrypted for security
  3. A transmission sent only in an emergency
  4. A transmission made without expecting a reply from the intended recipient Correct answer.

Explanation

A blind transmission is one made without expecting a reply, often used when contact cannot be established or when passing information to aircraft that may be listening. It differs from a routine two-way exchange because no response is anticipated. It is not reserved for emergencies or for ground stations.

Question 43Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

An aircraft is cleared to maintain FL 330 in airspace where the standard pressure setting applies. What does this mean for the altimeter subscale?

  1. It is set to the pressure at the transition altitude
  2. It is set to 1013.2 hPa Correct answer.
  3. It is set to the lowest forecast pressure on the route
  4. It is set to the aerodrome QNH

Explanation

Above the transition level, aircraft fly at flight levels referenced to the standard pressure setting of 1013.2 hPa. This ensures that all aircraft at high altitude use a common reference, so vertical separation is consistent. Aerodrome QNH is used below the transition level.

Question 44Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

What is the main benefit of the reduced separation minimum applied in certain radar environments?

  1. It eliminates the need for radio communication
  2. It guarantees a constant wind at all levels
  3. It removes the need for vertical separation entirely
  4. It allows more aircraft to be handled within the same airspace Correct answer.

Explanation

Reduced separation minima, applied where radar coverage and communication performance meet specified criteria, allow more aircraft to be accommodated in the same volume of airspace. They do not remove the need for vertical separation or radio communication. They depend on meeting strict technical and procedural conditions.

Question 45Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

A controller must pass traffic information to an aircraft about a nearby aircraft. Which items are most relevant to include?

  1. The other aircraft's maintenance history
  2. Relative position, direction of movement, and type or level of the conflicting traffic Correct answer.
  3. The other aircraft's fuel state and destination
  4. The other pilot's name and licence number

Explanation

Effective traffic information gives the pilot enough to locate and avoid the other aircraft, typically including relative bearing or position, direction of flight, and type or altitude. Fuel state and personal details do not help the pilot see and avoid. Concise, relevant information reduces frequency congestion.

Question 46Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

An aircraft is on a heading that will bring it into conflict with another aircraft at the same level, and the controller intends to use vertical separation. What must be assured before issuing the instruction?

  1. That both aircraft have the same destination
  2. That both aircraft have filed IFR flight plans
  3. That the climb or descent will achieve the required vertical separation before the aircraft converge Correct answer.
  4. That both aircraft are on the same frequency

Explanation

Vertical separation only resolves the conflict if the level change is completed, or separation is otherwise assured, before the aircraft lose horizontal spacing. The controller must consider aircraft performance and closure rate. Frequency and destination do not affect the separation calculation.

Question 47Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

Why is a pilot's report of "established on the ILS" important to a controller sequencing arrivals?

  1. It confirms the aircraft has completed its descent to the minima
  2. It confirms the aircraft has landed
  3. It confirms the aircraft has switched to the tower frequency
  4. It confirms the aircraft is tracking the localizer and can be expected to follow the approach path Correct answer.

Explanation

Establishing on the ILS indicates the aircraft is tracking the localizer and can be expected to follow the published approach path, which helps the controller judge spacing to the preceding aircraft. It does not mean the aircraft has landed or reached minima. Frequency changes are handled separately.

Question 48Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

A controller is planning to use a radar separation minimum between two aircraft whose tracks are diverging. What consideration most affects whether the minimum can be applied safely?

  1. Whether both aircraft have the same transponder code
  2. Whether both aircraft have the same destination
  3. Whether both aircraft are on the same heading
  4. Whether the divergence is sufficient to ensure separation increases after the closest point of approach Correct answer.

Explanation

When tracks diverge, separation initially decreases to a closest point of approach and then increases. The controller must be satisfied that the minimum is not infringed at that closest point. Transponder codes, headings, and destinations do not by themselves resolve the geometry.

Question 49Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

What is the operational significance of the transition level being higher than the transition altitude?

  1. It ensures that the same pressure setting is not used simultaneously for aircraft above and below the transition layer Correct answer.
  2. It removes the need for a QNH setting at the aerodrome
  3. It requires all aircraft to use QFE for approach
  4. It means aircraft must always fly at flight levels below the transition altitude

Explanation

The transition layer separates the region where QNH is used from the region where the standard pressure setting applies. Because the transition level is always at or above the transition altitude, no two aircraft using different pressure references occupy the same level in that layer. This prevents a vertical separation error caused by differing altimeter settings.

Question 50Air Traffic Control / Air Navigation Services (content domains not enumerated in source)

A controller notices that an aircraft's Mode C display differs significantly from the assigned level while the aircraft reports level flight. What is the most likely explanation to consider first?

  1. An error in the flight plan route
  2. An incorrect pressure setting on the aircraft's altimeter subscale Correct answer.
  3. A change in the aerodrome's runway in use
  4. A failure of the aircraft's radio transmitter

Explanation

Mode C reports pressure altitude referenced to 1013.2 hPa, so if the aircraft's altimeter subscale is set incorrectly, the Mode C display can differ from the assigned level. The controller should query the aircraft's altitude and altimeter setting. Radio, route, and runway changes do not directly explain a Mode C discrepancy.