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Brunei DCA CPL(A) Performance study materials
Brunei DCA CPL(A) Performance study resources

Brunei DCA CPL(A) Performance practice questions

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Question 1Aeroplane performance legislation, definitions and terminology

Under Brunei DCA performance requirements, which speed is defined as the speed at which the aeroplane is assumed to have reached 35 ft above the take-off surface during a take-off?

  1. V1, the decision speed
  2. V2, the take-off safety speed Correct answer.
  3. VLOF, the lift-off speed
  4. VR, the rotation speed

Explanation

V2 is the take-off safety speed, the speed that must be attained at 35 ft above the take-off surface with one engine inoperative and maintained to at least 400 ft. It is the reference speed used to demonstrate the take-off flight path clearance.

Question 2Aeroplane performance legislation, definitions and terminology

In performance terminology, what does the term 'accelerate-stop distance available' relate to?

  1. The distance needed to accelerate from V1 to V2 with all engines operating
  2. The runway length required to accelerate to V1 and then bring the aeroplane to a full stop Correct answer.
  3. The distance covered during the initial climb to 1500 ft
  4. The length of runway remaining after the last touchdown point

Explanation

The accelerate-stop distance is the total distance from the start of the take-off run to the point where the aeroplane is brought to a complete stop after failure of the critical engine at V1. It must not exceed the accelerate-stop distance available declared for the runway.

Question 3Aeroplane performance legislation, definitions and terminology

Which of the following best describes the 'take-off distance required' for a multi-engine aeroplane?

  1. The distance from brake release to lift-off with all engines operating
  2. The distance covered between VR and V2
  3. The distance from the start of the take-off run to the point where V1 is reached
  4. The horizontal distance from the start of the take-off run to the point where the aeroplane reaches 35 ft, with one engine inoperative Correct answer.

Explanation

The take-off distance required is measured from the start of the take-off run to the point where the aeroplane attains 35 ft above the take-off surface, assuming the critical engine fails at V1. It must not exceed the take-off distance available.

Question 4Aeroplane performance legislation, definitions and terminology

What is the meaning of 'unbalanced field length' in take-off performance?

  1. A field where the runway slopes upward significantly
  2. A field where the landing distance exceeds the take-off distance
  3. A field where the take-off is limited by obstacle clearance rather than runway length
  4. A field where V1 is chosen so that the accelerate-stop distance and take-off distance are both equal to the available length Correct answer.

Explanation

An unbalanced field exists when V1 is selected so that the accelerate-stop distance equals the take-off distance, both being equal to the field length available. This gives the maximum permissible V1 for a given runway and is used when field length is limiting.

Question 5Aeroplane performance legislation, definitions and terminology

Which term describes the maximum mass at which the aeroplane can climb from the take-off surface to 1500 ft with one engine inoperative?

  1. Maximum landing mass
  2. Maximum mass for the take-off flight path Correct answer.
  3. Maximum take-off mass
  4. Maximum zero-fuel mass

Explanation

The maximum mass for the take-off flight path is the limiting mass at which the required climb gradient can be achieved with the critical engine inoperative from 35 ft to 1500 ft. It is one of several limiting masses that together determine the actual take-off mass.

Question 6Aeroplane performance legislation, definitions and terminology

What does 'VMCG' represent in aeroplane performance?

  1. The minimum control speed in the air with the critical engine inoperative
  2. The speed at which the aeroplane can climb on one engine
  3. The maximum speed for retracting the landing gear
  4. The minimum control speed on the ground with the critical engine inoperative Correct answer.

Explanation

VMCG is the minimum control speed on the ground, the lowest speed at which directional control can be maintained with the critical engine inoperative and the other at take-off power. It is determined without relying on the nose-wheel steering.

Question 7Aeroplane performance legislation, definitions and terminology

In landing performance, what is the 'landing distance required'?

  1. The distance from 50 ft above the landing surface to a full stop Correct answer.
  2. The distance from 1500 ft to touchdown
  3. The distance from the threshold to the touchdown point
  4. The distance covered during the landing roll only

Explanation

The landing distance required is measured from the point where the aeroplane is 50 ft above the landing surface, through touchdown, to a complete stop. It must not exceed the landing distance available, and a safety factor is applied for the actual conditions.

Question 8Aeroplane performance legislation, definitions and terminology

Which of the following describes the 'net take-off flight path'?

  1. The gross flight path reduced by a specified gradient decrement to account for pilot technique and turbulence Correct answer.
  2. The path required to clear all obstacles by 35 ft
  3. The actual flight path achieved with all engines operating
  4. The flight path flown after the landing gear is retracted

Explanation

The net take-off flight path is the gross flight path reduced by a specified gradient decrement, typically 0.8 percent for two-engine aeroplanes and 0.9 percent for three-engine aeroplanes. This net path must clear all obstacles by the required margin.

Question 9Aeroplane performance legislation, definitions and terminology

What is the significance of the 'screen height' in take-off performance?

  1. It is the height of obstacles surrounding the aerodrome
  2. It is the altitude at which the aeroplane levels off after take-off
  3. It is the height of the landing gear above the runway
  4. It is the reference height of 35 ft above the take-off surface at the end of the take-off distance Correct answer.

Explanation

The screen height is the reference height, 35 ft for take-off, at which the take-off distance ends and the flight path begins. It allows for the transition from the ground run to a stabilised climb.

Question 10Aeroplane performance legislation, definitions and terminology

Which of the following best defines 'maximum zero-fuel mass'?

  1. The maximum mass of the aeroplane excluding usable fuel Correct answer.
  2. The maximum mass of the aeroplane with fuel tanks empty
  3. The maximum mass at which the aeroplane can land
  4. The maximum mass at which the aeroplane can take off

Explanation

Maximum zero-fuel mass is the maximum mass of the aeroplane with all usable fuel exhausted, leaving only unusable fuel and other specified items. It limits the payload that can be carried for a given fuel load.

Question 11Aeroplane performance legislation, definitions and terminology

In the context of performance legislation, what is meant by 'contaminated runway'?

  1. A runway with a displaced threshold
  2. A runway with a downhill slope
  3. A runway with a rough surface texture
  4. A runway with standing water, slush, snow or ice that affects braking Correct answer.

Explanation

A contaminated runway is one where a significant layer of standing water, slush, snow, ice or other contaminant is present and reduces braking action or affects acceleration. Performance data must be adjusted accordingly.

Question 12Aeroplane performance legislation, definitions and terminology

Which of the following describes the 'balanced field length'?

  1. The runway length required for a one-engine climb
  2. The runway length required for landing
  3. The runway length where take-off distance equals accelerate-stop distance Correct answer.
  4. The runway length required for a normal take-off with all engines

Explanation

Balanced field length is the runway length at which the take-off distance and the accelerate-stop distance are equal, corresponding to a specific V1. It represents the most efficient use of the available runway.

Question 13Aeroplane performance legislation, definitions and terminology

What is the meaning of 'VLE' in aeroplane performance?

  1. The minimum control speed in the air
  2. The maximum speed with the landing gear extended Correct answer.
  3. The maximum speed at which the landing gear can be retracted
  4. The speed for best angle of climb

Explanation

VLE is the maximum speed at which the aeroplane may be flown with the landing gear extended. It is a structural and aerodynamic limitation that must be respected in performance planning.

Question 14Aeroplane performance legislation, definitions and terminology

Which of the following best describes 'obstacle clearance' in the net take-off flight path?

  1. The vertical distance between the net flight path and the obstacle Correct answer.
  2. The distance from the start of the take-off run to the obstacle
  3. The horizontal distance between the runway and the obstacle
  4. The height of the obstacle above sea level

Explanation

Obstacle clearance is the vertical margin between the net take-off flight path and the highest obstacle along the departure path. The net path must clear all obstacles by a specified margin to ensure safe departure.

Question 15Aeroplane performance legislation, definitions and terminology

What does 'VREF' represent in landing performance?

  1. The speed for best glide
  2. The landing reference speed at the threshold Correct answer.
  3. The minimum control speed on the ground
  4. The maximum speed for flap extension

Explanation

VREF is the landing reference speed, the speed at the threshold used for landing performance calculations. It is typically 1.3 times the stalling speed in the landing configuration.

Question 16Aeroplane performance legislation, definitions and terminology

Which of the following describes the 'take-off flight path' requirement for a two-engine aeroplane?

  1. It must reach 400 ft before the end of the runway
  2. It must clear all obstacles by a specified margin and reach 1500 ft above the take-off surface Correct answer.
  3. It must be flown at V2 until 1500 ft
  4. It must clear all obstacles by at least 35 ft

Explanation

The take-off flight path must clear all obstacles along the route by the required margin and continue to 1500 ft above the take-off surface. The net flight path is used for this obstacle clearance analysis.

Question 17Aeroplane performance legislation, definitions and terminology

In performance planning, what is the effect of a tailwind on the take-off distance?

  1. It reduces the accelerate-stop distance
  2. It decreases the take-off distance required
  3. It has no effect on the take-off distance
  4. It increases the take-off distance required Correct answer.

Explanation

A tailwind increases the ground speed for a given airspeed, so the aeroplane covers more ground during the take-off run, increasing the take-off distance required. Performance data must be corrected for wind.

Question 18Aeroplane performance legislation, definitions and terminology

Which of the following best describes the term 'pressure altitude'?

  1. The height above the terrain
  2. The altitude indicated when the altimeter is set to 1013.25 hPa Correct answer.
  3. The altitude indicated when the altimeter is set to QNH
  4. The altitude above the aerodrome

Explanation

Pressure altitude is the altitude indicated when the altimeter subscale is set to the standard pressure of 1013.25 hPa. It is used as the basis for performance charts because engine and aerodynamic performance depend on pressure.

Question 19Aeroplane performance legislation, definitions and terminology

What is the meaning of 'density altitude'?

  1. The altitude indicated by the radio altimeter
  2. The altitude of the aerodrome above sea level
  3. The pressure altitude corrected for temperature deviation from standard Correct answer.
  4. The altitude at which the aeroplane reaches V2

Explanation

Density altitude is the pressure altitude corrected for non-standard temperature. It reflects the density of the air and directly affects engine power and lift, making it a key input to performance charts.

Question 20Aeroplane performance legislation, definitions and terminology

Which of the following best describes the 'maximum landing mass'?

  1. The maximum mass with fuel tanks empty
  2. The maximum mass for the take-off flight path
  3. The maximum mass at which the aeroplane may land Correct answer.
  4. The maximum mass at which the aeroplane may take off

Explanation

Maximum landing mass is the structural limit for the aeroplane at touchdown. It may be higher than the maximum zero-fuel mass but lower than the maximum take-off mass.

Question 21Atmospheric physics and the International Standard Atmosphere

In the International Standard Atmosphere, what is the sea-level temperature?

  1. 15 degrees Celsius Correct answer.
  2. 20 degrees Celsius
  3. 0 degrees Celsius
  4. 10 degrees Celsius

Explanation

The ISA is defined with a mean sea-level temperature of 15 degrees Celsius, together with a sea-level pressure of 1013.25 hPa. These reference values anchor all subsequent lapse-rate calculations used in aircraft performance.

Question 22Atmospheric physics and the International Standard Atmosphere

What is the standard sea-level pressure used in the International Standard Atmosphere?

  1. 1013.25 hPa Correct answer.
  2. 1020 hPa
  3. 950 hPa
  4. 1000 hPa

Explanation

The ISA defines mean sea-level pressure as 1013.25 hectopascals, equivalent to 29.92 inches of mercury. This value is the datum from which pressure altitude and all pressure-ratio performance calculations are derived.

Question 23Atmospheric physics and the International Standard Atmosphere

In the lower atmosphere up to 11 km, the ISA temperature lapse rate is approximately:

  1. 2 degrees Celsius per 1000 ft
  2. 1.98 degrees Celsius per 1000 ft Correct answer.
  3. 6.5 degrees Celsius per 1000 ft
  4. 3 degrees Celsius per 1000 ft

Explanation

The ISA troposphere uses a lapse rate of about 1.98 degrees Celsius per 1000 ft, which is 6.5 degrees Celsius per kilometre. This constant decrease continues up to the tropopause at 11 km.

Question 24Atmospheric physics and the International Standard Atmosphere

At what altitude does the ISA tropopause occur, and what happens to temperature above it?

  1. 8 km, temperature continues to fall
  2. 11 km, temperature rises immediately
  3. 20 km, temperature remains constant
  4. 11 km, temperature remains constant to 20 km Correct answer.

Explanation

The ISA tropopause is placed at 11 km (about 36,090 ft). Above it, in the isothermal layer, temperature stays constant at minus 56.5 degrees Celsius up to 20 km.

Question 25Atmospheric physics and the International Standard Atmosphere

Which statement best describes the relationship between density altitude and aircraft performance?

  1. Higher density altitude improves engine power and lift
  2. Higher density altitude degrades engine power, lift and propeller thrust Correct answer.
  3. Density altitude has no effect on performance
  4. Density altitude affects only pressurisation systems

Explanation

Density altitude expresses air density in terms of the altitude at which that density occurs in the standard atmosphere. As density altitude rises, air density falls, reducing engine power, lift and propeller thrust, and increasing take-off and landing distances.

Question 26Atmospheric physics and the International Standard Atmosphere

Pressure altitude is defined as the altitude indicated when the altimeter subscale is set to:

  1. 1013.25 hPa Correct answer.
  2. The aerodrome elevation
  3. The standard temperature value
  4. The local QNH

Explanation

Pressure altitude is the height above the 1013.25 hPa pressure surface, obtained by setting the altimeter to standard pressure. It is the basis for flight levels and for performance charts referenced to the standard atmosphere.

Question 27Atmospheric physics and the International Standard Atmosphere

An aircraft is at an aerodrome where the QNH is 1013 hPa and the temperature is 30 degrees Celsius. Compared with the ISA, the air density at that aerodrome is:

  1. Lower than ISA, giving worse performance Correct answer.
  2. Exactly the same as ISA
  3. Higher, but only for jet engines
  4. Higher than ISA, giving better performance

Explanation

With QNH equal to standard pressure, pressure altitude equals elevation, but the temperature is well above the ISA value for that elevation. Warmer-than-standard air is less dense, so density altitude exceeds pressure altitude and performance is degraded.

Question 28Atmospheric physics and the International Standard Atmosphere

An aerodrome at 2000 ft elevation reports QNH 1013 hPa and a temperature of 15 degrees Celsius. Its density altitude is approximately:

  1. 2000 ft Correct answer.
  2. 500 ft
  3. 1000 ft
  4. 4000 ft

Explanation

QNH equal to 1013 hPa makes pressure altitude equal elevation, and 15 degrees Celsius happens to equal the ISA temperature at 2000 ft (15 minus about 4 degrees). Since temperature and pressure both match ISA, density altitude equals pressure altitude, about 2000 ft.

Question 29Atmospheric physics and the International Standard Atmosphere

As an aircraft climbs in the standard atmosphere, how do pressure, temperature and density behave in the troposphere?

  1. Only pressure decreases
  2. Pressure and density decrease while temperature stays constant
  3. Pressure decreases, temperature decreases, density increases
  4. All three decrease with height Correct answer.

Explanation

In the troposphere of the ISA, pressure, temperature and density all decrease as height increases. Pressure falls because there is less overlying air, temperature falls at the lapse rate, and density falls as a consequence of both.

Question 30Atmospheric physics and the International Standard Atmosphere

Why does the tropopause occur at a lower altitude over the poles than over the equator?

  1. Polar pressure is higher at all levels
  2. The poles are closer to the Earth's axis
  3. Polar air is colder and denser, so the troposphere is shallower Correct answer.
  4. The ISA defines a single tropopause everywhere

Explanation

Tropospheric depth depends on surface heating and convective mixing. Cold, dense polar air produces weaker convection, so the tropopause sits lower, around 8 km, while warm equatorial air pushes it to about 16 km.

Question 31Atmospheric physics and the International Standard Atmosphere

What does the term 'humidity effect' mean for aircraft performance on a hot day?

  1. Water vapour makes air less dense, further reducing performance Correct answer.
  2. Water vapour makes air more dense, improving performance
  3. Humidity cancels the temperature effect
  4. Humidity affects only radio performance

Explanation

Water vapour is lighter than the dry air it displaces, so moist air is less dense than dry air at the same pressure and temperature. On an already hot day, high humidity therefore adds to the density-altitude penalty.

Question 32Atmospheric physics and the International Standard Atmosphere

Which combination produces the highest density altitude for a given aerodrome elevation?

  1. High pressure, high temperature, dry air
  2. High pressure, low temperature, low humidity
  3. Low pressure, high temperature, high humidity Correct answer.
  4. Standard pressure, standard temperature, dry air

Explanation

Density altitude rises when pressure is low and when temperature and humidity are high, because each of these reduces air density. The worst case for performance is therefore low pressure combined with hot, humid air.

Question 33Atmospheric physics and the International Standard Atmosphere

What is the ISA sea-level density value used in performance calculations?

  1. 1.000 kg per cubic metre
  2. 1.225 kg per cubic metre Correct answer.
  3. 0.905 kg per cubic metre
  4. 1.500 kg per cubic metre

Explanation

The ISA defines sea-level density as 1.225 kilograms per cubic metre at 15 degrees Celsius and 1013.25 hPa. Density ratios in performance charts are referenced to this value.

Question 34Atmospheric physics and the International Standard Atmosphere

An aircraft departs an aerodrome at 5000 ft pressure altitude where the temperature is ISA plus 20 degrees Celsius. Compared with ISA conditions, the true airspeed for a given indicated airspeed will be:

  1. Higher, because the air is denser
  2. Lower, because the air is denser
  3. Higher, because the air is less dense Correct answer.
  4. Unchanged, because IAS and TAS are always equal

Explanation

True airspeed exceeds indicated airspeed as air density falls, because the same dynamic pressure corresponds to a greater true speed in thinner air. A temperature 20 degrees above ISA lowers density further, increasing the TAS for a given IAS.

Question 35Atmospheric physics and the International Standard Atmosphere

How does the ISA model temperature between 20 km and 32 km?

  1. It decreases at the standard lapse rate
  2. It increases with height Correct answer.
  3. It decreases at twice the standard lapse rate
  4. It remains constant

Explanation

Above the isothermal layer ending at 20 km, the ISA specifies a temperature increase with height up to about 32 km. This warming region lies in the lower stratosphere, where ozone absorption raises temperature.

Question 36Atmospheric physics and the International Standard Atmosphere

Two aerodromes have the same elevation, but one reports QNH 1003 hPa and the other 1023 hPa. Which statement is correct?

  1. Both have identical density altitude
  2. The low-pressure aerodrome has the higher density altitude Correct answer.
  3. Pressure does not affect density altitude
  4. The high-pressure aerodrome has the higher density altitude

Explanation

Lower QNH means the 1013.25 hPa surface lies above the aerodrome, so pressure altitude exceeds elevation. Higher pressure altitude at the same temperature means higher density altitude and reduced performance.

Question 37Atmospheric physics and the International Standard Atmosphere

An aerodrome elevation is 3000 ft and the QNH is 1023 hPa. What is the approximate pressure altitude?

  1. 3270 ft Correct answer.
  2. 2730 ft
  3. 330 ft
  4. 3000 ft

Explanation

Each hectopascal above 1013 hPa corresponds to about 27 ft of pressure altitude. Ten hectopascals above standard adds roughly 270 ft, so pressure altitude is about 3000 plus 270, or 3270 ft.

Question 38Atmospheric physics and the International Standard Atmosphere

An aircraft flies at a constant indicated altitude from a warm air mass into a cold air mass, with the altimeter subscale unchanged. What happens to its true altitude?

  1. It decreases below the indicated altitude Correct answer.
  2. It increases above the indicated altitude
  3. It stays equal to the indicated altitude
  4. It increases only if pressure also rises

Explanation

An altimeter assumes ISA temperature. In colder air the pressure levels are compressed closer to the ground, so the aircraft is lower than the altimeter suggests. Flying from warm to cold air therefore reduces true altitude while indicated altitude stays constant.

Question 39Atmospheric physics and the International Standard Atmosphere

At 15,000 ft in the ISA, which statement about the density ratio is correct?

  1. It equals one because density is constant
  2. It is equal to the pressure ratio
  3. It is lower than the pressure ratio at the same level Correct answer.
  4. It is higher than the pressure ratio

Explanation

Density falls faster than pressure with height because temperature also decreases. The density ratio is therefore smaller than the pressure ratio at any tropospheric level above sea level, which is why density altitude exceeds pressure altitude in standard conditions.

Question 40Atmospheric physics and the International Standard Atmosphere

An aerodrome at 4000 ft elevation has QNH 1000 hPa and a temperature of ISA plus 15 degrees Celsius. Which factor contributes most to the resulting high density altitude?

  1. The high temperature alone
  2. Neither, because elevation dominates
  3. The combination of low pressure and high temperature Correct answer.
  4. The low pressure alone

Explanation

Both a low QNH and an above-ISA temperature act to reduce density, and their effects accumulate. The pressure deficit adds roughly 350 ft of pressure altitude, while the temperature excess adds several hundred feet more, so the combination gives the highest density altitude.

Question 41Take-off performance: field length, obstacle and climb-limited cases

In take-off performance planning, the take-off distance required (TODR) is measured from the start of the take-off roll to the point where the aeroplane:

  1. achieves V1 with the critical engine failed
  2. becomes airborne and the wheels leave the ground
  3. reaches 50 ft above the runway surface with all engines operating Correct answer.
  4. reaches 35 ft above the runway surface with all engines operating

Explanation

The take-off distance required ends at the point where the aeroplane has climbed to 50 ft above the take-off surface with all engines operating. Reaching 35 ft corresponds to the landing distance definition, not take-off. The screen height of 50 ft is the standard reference used in performance planning.

Question 42Take-off performance: field length, obstacle and climb-limited cases

The take-off run required (TORR) is the horizontal distance from the start of the take-off roll to the point where the aeroplane:

  1. becomes airborne with all engines operating Correct answer.
  2. reaches V2 with one engine failed
  3. reaches 50 ft above the runway
  4. passes the end of the clearway

Explanation

The take-off run is the ground distance consumed from brake release until the aeroplane becomes airborne. It does not include the airborne segment up to 50 ft, which belongs to take-off distance. Clearway is associated with the overall take-off distance available, not the run.

Question 43Take-off performance: field length, obstacle and climb-limited cases

Which statement correctly describes the take-off distance available (TODA) on a runway with a clearway?

  1. It equals the take-off run available plus the full clearway length Correct answer.
  2. It equals the take-off run available plus half the clearway length
  3. It equals the runway length only, since clearway cannot be used
  4. It equals the take-off run available plus twice the clearway length

Explanation

TODA is the take-off run available plus the length of any clearway, provided the clearway does not exceed half the take-off run available. The full clearway length is added, subject to that limit. The runway length alone is only the take-off run available.

Question 44Take-off performance: field length, obstacle and climb-limited cases

What is the principal purpose of a stopway at the end of a runway?

  1. To provide additional take-off run for heavy departures
  2. To allow the aeroplane to accelerate before brake release
  3. To support an aeroplane during a rejected take-off without structural damage Correct answer.
  4. To permit the aeroplane to climb to 50 ft after liftoff

Explanation

A stopway is a cleared, prepared area beyond the runway end intended to stop an aeroplane during an abandoned take-off. It must be able to support the aeroplane without causing structural damage. It is not used for acceleration, climb, or normal take-off run.

Question 45Take-off performance: field length, obstacle and climb-limited cases

For a dry runway, the take-off distance required must not exceed the take-off distance available by more than:

  1. zero; the required distance must fit within the available distance Correct answer.
  2. 5 per cent of the available distance
  3. 10 per cent of the available distance
  4. 15 per cent of the available distance

Explanation

On a dry runway the scheduled take-off distance required, including any required factoring, must not exceed the take-off distance available. There is no discretionary percentage overshoot permitted. The whole required distance must be contained within the available distance.

Question 46Take-off performance: field length, obstacle and climb-limited cases

When the take-off is limited by obstacle clearance, which speed should be attained by 35 ft above the runway surface with all engines operating?

  1. VR
  2. V1
  3. VLO
  4. V2 Correct answer.

Explanation

The take-off flight path begins at 35 ft with the aeroplane at V2, the take-off safety speed. V2 provides the scheduled climb gradient used for obstacle analysis. V1 and VR are ground-phase speeds, and VLO relates to landing gear operation.

Question 47Take-off performance: field length, obstacle and climb-limited cases

In the one-engine-inoperative take-off flight path, the net gradient used for obstacle clearance is obtained by:

  1. using the gross gradient without reduction
  2. subtracting 0.8 per cent from the gross gradient
  3. adding 0.9 per cent to the gross gradient
  4. subtracting 0.9 per cent from the gross gradient Correct answer.

Explanation

For two-engine aeroplanes the net take-off flight path is the gross gradient reduced by 0.9 per cent. This reduction accounts for pilot technique and turbulence. Obstacle clearance is then checked against the net path.

Question 48Take-off performance: field length, obstacle and climb-limited cases

Which factor increases the take-off ground run for a given aeroplane mass?

  1. A tailwind component Correct answer.
  2. A headwind component
  3. A lower outside air temperature
  4. A lower aerodrome pressure altitude

Explanation

A tailwind reduces the airspeed achieved for a given groundspeed, so more runway is needed to reach the required speeds. Higher temperature, higher pressure altitude and headwinds all have the opposite effect on the ground run. Tailwind therefore lengthens the take-off run.

Question 49Take-off performance: field length, obstacle and climb-limited cases

An aerodrome has a take-off run available of 1800 m and a clearway of 150 m. What is the take-off distance available?

  1. 1875 m
  2. 1650 m
  3. 1950 m Correct answer.
  4. 1800 m

Explanation

TODA equals TORA plus the clearway length, so 1800 m plus 150 m gives 1950 m. The clearway is within the permitted limit of half the TORA. The other values misapply or omit the clearway.

Question 50Take-off performance: field length, obstacle and climb-limited cases

With a take-off mass of 60 000 kg, the AFM gives a take-off distance required of 2100 m at the ambient conditions. The TODA is 2400 m. What is the maximum additional obstacle-limited mass reduction likely required?

  1. The full difference between TODA and TODR must be converted to mass
  2. Only the amount needed so that the net flight path clears all obstacles Correct answer.
  3. None, since TODR is below TODA
  4. A reduction is always required regardless of obstacles

Explanation

Field length is satisfied because TODR is less than TODA, but obstacle clearance must still be checked. Mass is reduced only to the extent needed for the net take-off flight path to clear all obstacles by the required margin. No automatic reduction follows merely from the distance margin.