Performance: 8 Latest ATPL Questions Solved

In this blog, we break down eight of the latest ATPL Performance questions reported across EASA authorities recently, using the freshest content from the Airhead Question Bank. Each question includes the correct answer, a clear explanation, and exam tips to help you score efficiently in the real exam.

This focused walkthrough covers critical Performance topics such as Constant Descent Arrivals (CDA), landing distance regulations, wet runway operations, and engine-out performance. 

📚 Questions covered in this article

• AIR-241769: Landing Distance Requirements on Wet Runways for Performance Class A Turboprop Aircraft

• AIR-241829: Cost Index — Definition and Operational Meaning in Flight Performance

• AIR-241902: Effect of Acceleration in Climb with Constant Power Setting

• AIR-241880: Landing Techniques to Minimise the Risk of Hydroplaning

• AIR-241657: Take-Off Configuration Selection for Best Climb Gradient

• AIR-242521: Landing Techniques for Wet Runway Operations During Heavy Rain

• AIR-242204: Effect of Headwind on Maximum Range Speed and Maximum Gradient Climb Speed

• AIR-241681: Centre of Gravity Position — Effects of Forward vs Aft CG on Performance

Watch the full walkthrough:  

On our Airhead YouTube channels, we publish regular question walkthroughs covering the latest reported ATPL questions — explained clearly and step by step. 

Watch full Performance walkthrough sessions on our YouTube channel and boost your exam confidence. 

In addition, the Airhead team, together with Michal (ATPL pilot), runs live and free revision sessions to help you practise the freshest questions shortly before your ATPL exam. Join us every week if you'd like to understand what the exam is really testing, avoid common traps, and answer faster — with clarity and reassurance.

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Question 1: Landing Distance on a Wet Runway 

Question ID AIR-241769: For a Performance Class A turbo-propeller powered aeroplane on a commercial flight, a 2200 m long runway at the destination aerodrome is expected to be wet. It must be ensured that the landing mass of the aeroplane allows a full stop landing on a dry runway within a landing distance of…

1. 1339 m

2. 1771 m

3. 1540 m

4. 1147 m

Correct Answer: 1339 m

Explanation: In Part-CAT, landing performance safety margins are expressed using the concept of Actual Landing Distance (ALD). The Aircraft Flight Manual (AFM) provides landing performance data under certification conditions. The ALD is defined as the distance from the screen height over the runway threshold to the point where the aircraft comes to a full stop on a dry runway.

To ensure operational safety, Part-CAT requires correction factors to be applied to the ALD. The resulting value is then compared against the Landing Distance Available (LDA).

What the examiner is really asking: Although the wording of the question may seem confusing, the examiner is asking you to work backwards: Given the available runway (LDA), what is the maximum ALD (dry runway) that may be taken from the AFM, once all regulatory factors are applied?

This is best understood by referring to the Part-CAT landing distance factor table.

Applicable factors (commercial operations)

For turboprop (Class B) aircraft:

• Dry runway factor: 70% → Regulatory factor = 1 / 0.70 = 1.43

• Wet runway correction: +15% → Multiply by 1.15

Total wet runway factor: 1.43 × 1.15 = 1.64

Calculation: Starting with the Landing Distance Available (LDA): 2,200 m

Work backwards to find the maximum allowable ALD:  2,200 ÷ 1.64 ≈ 1,341 m

This value (≈ 1,340 m) is the longest dry-runway ALD that may be taken from the AFM.

Exam Tip 

• Memorise the regulatory factors: 70% for turboprops (Class B) and 60% for jets

• The wet runway correction is always +15% (×1.15) unless the AFM explicitly provides wet-runway data.

• When wording feels awkward, ask yourself: “Am I being asked to work forward from the AFM, or backwards from the LDA?”

This mindset alone will save you time — and marks — in the exam. 

Question 2: Cost Index Definition

Question ID AIR-241829: In relation to flight performance, what does the term 'Cost Index' define?

1. A number denoting the ratio of the costs of crew and maintenance to the cost of the fuel.

2. A number denoting the ratio of the cost of fuel to speed.

3. A number denoting the cost per nautical mile.

4. A number denoting the ratio of direct operating costs to speed.

Correct Answer: A number denoting the ratio of the costs of crew and maintenance to the cost of the fuel. 

Explanation: The Cost Index (CI) represents the ratio of aircraft operating expenses (such as crew, maintenance, and time-related costs) to the cost of fuel.

Airlines calculate this ratio using internal economic models and present it as a single number on the flight plan, which the crew then enters into the FMS. The FMS uses the Cost Index to optimise speed profiles throughout the flight.

• A higher Cost Index commands higher speeds, resulting in greater fuel burn but shorter flight time.

• A lower Cost Index favours fuel efficiency, with slower speeds and longer flight time.

At a Cost Index of 0, fuel cost is the only priority, and the aircraft flies at maximum range speed (VMR).

Key Points to Remember

• Low CI (e.g. 0): Fuel-saving priority → slower speeds

• High CI (maximum): Time-saving priority → faster speeds, higher fuel burn

• Cost Index does not set a speed directly: It influences the FMS calculations for climb, cruise, and descent profiles.

Exam Tip: Long Range Cruise (LRC) is related to fuel economy but is not the same as Cost Index. If an answer mentions time vs fuel trade-off, think Cost Index. If the question refers to best range or endurance speeds, think performance speeds, not CI.

Question 3: Acceleration in Climb with Constant Power

Question ID AIR-241902: Any acceleration in climb, with a constant power setting will:

1. decreases the rate of climb and the angle of climb.

2. decreases rate of climb and increases angle of climb.

3. improves the climb gradient if the airspeed is below Vx.

4. improves the rate of climb if the airspeed is below Vy.

Correct Answer: decreases the rate of climb and the angle of climb.

To accelerate without increasing the power setting, the aircraft must lower the nose. This causes energy to be diverted from potential energy (height) to kinetic energy (speed).

This situation typically occurs at the acceleration altitude after take-off, when the aircraft pitches down to increase speed for flap retraction and climb clean-up.

Immediate Effects

• Lower pitch angle → reduced angle of climb

• Temporary reduction in rate of climb (ROC)

• Energy is transferred from climb performance to acceleration

Once the target speed is reached, climb performance may recover. However, the question refers specifically to the acceleration phase, not the steady-state climb that follows.

Exam Tip: Think acceleration altitude logic, not Vy theory. In exams, temporary effects matter — focus on what happens during acceleration, not after it.

Question 4: Minimising Hydroplaning Risk on Landing

Question ID AIR-241880: To minimise the risk of hydroplaning during landing the pilot should:

1. use maximum reverse thrust, and should start braking below the hydroplaning speed.

2. use normal landing-, braking- and reverse technique.

3. postpone the landing until the risk of hydroplaning no longer exists.

4. make a positive landing and apply maximum reverse thrust and brakes as quickly as possible.

Correct Answer: make a positive landing and apply maximum reverse thrust and brakes as quickly as possible.

Explanation: To minimise the risk of hydroplaning during landing, the pilot should aim for a firm (positive) touchdown and apply reverse thrust and braking promptly. This brings the aircraft speed below the hydroplaning speed (Vp) as quickly as possible.

A firm touchdown is essential because it:

• Breaks the surface tension of water or contaminants

• Ensures the wheels spin up quickly

• Allows the brakes to become effective sooner

With antiskid active, firm braking can be applied without wheel lock, maximising deceleration while maintaining control.

Hydroplaning speed depends on tyre pressure (p, in psi):

• Dynamic hydroplaning: Vp = 9 × √p

• Viscous hydroplaning: Vp = 7.7 × √p

Reducing speed below Vp as early as possible is key to stopping safely on a contaminated runway.

Exam Tip: “Firm touchdown” does not mean unsafe or hard landing. Soft landings increase hydroplaning risk by delaying wheel spin-up and braking effectiveness. 

Question 5: Take-off Configuration for Best Climb Gradient

Question ID AIR-241657: A jet aeroplane has three configurations available for take-off: 

• T/O 1: 1 stage of slats and flaps. 

• T/O 2: 2 stages of slats and flaps. 

• T/O 3: 2 stages of slats and 3 stages of flaps. 

The runway is NOT limiting but the given departure requires a climb gradient of 6.8 % to 6000 ft. In order to achieve the best climb gradient, which T/O configuration will be most appropriate?

1. T/O 1 because it results in greater climb speeds and a greater rate of climb than when using T/O 2.

2. T/O 2 because it results in lower climb speeds and a greater rate of climb than when using T/O 3. 

3. T/O 3 because it results in greater climb speeds and a greater rate of climb than when using T/O 1.

4. T/O 1 because it results in lower climb speeds, giving a higher angle of climb than when using T/O 2.

Correct Answer: T/O 1 because it results in greater climb speeds and a greater rate of climb than when using T/O 2.

Explanation: Since the runway is not limiting, the lowest safe flap setting should be used for take-off. This configuration produces less drag, allowing a higher climb speed and placing the aircraft closer to Vx (best angle of climb speed), which improves the climb gradient.

While flaps do increase lift, they also significantly increase drag. When runway length is available, minimising drag is the key to achieving the best climb performance.

Exam Tip

• Best climb gradient = cleanest safe configuration

• Always check whether the runway is a limiting factor before selecting take-off flap settings.

Question 6: Landing Technique on Frequently Wet Runways

Question ID AIR-242521: During the rainy season the runways are frequently wet following heavy rain showers. What landing techniques should be adopted when operating on such runways? 

1. Positive landings with prompt full application of all retardation devices and maximum brake/autobrake with anti-skid.

2. Use of reverse thrust should be kept to a minimum to avoid water spray and impingement, and anti-skid braking should be applied slowly to avoid hydroplaning.

3. Light touchdown landings with maximum airbrake and reverse thrust but minimum anti-skid braking.

4. It is vital to maintain a normal approach and landing technique but use a slower approach and landing speed compared to dry runway operations.

Correct Answer: Positive landings with prompt full application of all retardation devices and maximum brake/autobrake with anti-skid.

Explanation: On wet runways, the priority is to minimise hydroplaning risk and maximise braking effectiveness immediately after touchdown. This requires a firm (positive) landing and prompt use of all available deceleration devices.

A firm touchdown ensures rapid wheel spin-up and breaks through the water film, allowing brakes and antiskid to become effective quickly. A soft landing delays wheel contact, increases hydroplaning risk, and lengthens the landing distance.

Reverse thrust should be applied immediately, as it provides deceleration independent of wheel braking and reduces brake demand.

Autobrakes aim for a preselected deceleration rate, not the shortest stopping distance. Maximum autobrake is typically reserved for RTO. For minimum landing distance, manual braking with antiskid provides the most effective deceleration.

Exam Tip 

• Manual braking + antiskid = shortest landing distance

• Autobrake provides comfort and consistency, not maximum braking force

• “Positive landing” means firm and safe, not abusive

Question 7: Effect of Headwind on Range and Climb Gradient Speeds

 Question ID AIR-242204: Compared with still-air, the effect a headwind has on the values of the maximum range speed and the maximum gradient climb speed respectively is that:

1. the maximum range speed increases and the maximum gradient climb speed is not affected.

2. the maximum range speed decreases and the maximum gradient climb speed is not affected.

3. the maximum range speed decreases and the maximum gradient climb speed increases.

4. the maximum range speed decreases and the maximum gradient climb speed decreases.

Correct Answer: the maximum range speed increases and the maximum gradient climb speed is not affected.

Explanation: The rule of thumb is to fly faster in a headwind and slightly slower in a tailwind for maximum range. The maximum climb angle speed Vx is unaffected by wind. 

• Best climb gradient speed (Vx) is aerodynamic → wind independent

• Best endurance speed is also wind independent

• Maximum range speed does change:

  • Headwind → fly faster Tailwind → fly slower

Exam Tip: Wind affects ground range, not aerodynamic optima

Question 8: Effect of Aft Centre of Gravity

Question ID AIR-241681: Assuming the gross mass, altitude and airspeed remain unchanged, moving the Centre of Gravity from the forward safe limit to the aft safe limit:

1. increases the power required.

2. affects neither drag nor power required.

3. increases the induced drag.

4. decreases the induced drag and reduces the power required.

Correct Answer: decreases the induced drag and reduces the power required.

Explanation: Moving the centre of gravity (CG) aft reduces the nose-down pitching moment. As a result, the tailplane requires less downward force to maintain equilibrium.

With less tail downforce, the wing no longer needs to generate as much additional lift to balance that force. This leads to a reduction in total lift required, which in turn reduces induced drag.

Less induced drag means: lower power required, improved fuel efficiency, and increased range

Additionally, though not specifically asked, an aft CG will generally result in a slightly lower stall speed (Vs) due to the reduced lift requirement.

CG Comparison

Forward CG:

• Greater tail downforce required

• Higher total lift required

• Increased induced drag

• More stable, but less efficient

Aft CG:

• Reduced tail downforce

• Lower total lift requirement

• Reduced induced drag

• More efficient, but less stable

Exam Tip: CG shifts alter drag and power required, not just stability. In performance questions, think: Forward CG = more drag Aft CG = less drag, better range.

Performance (Aeroplane) Exam Overview 

To support your revision, here’s a concise overview of what to expect in the ATPL Performance exam, including format, timing, and difficulty — plus practical guidance to help you prepare effectively.

Number of Questions: 45 Exam Duration: 2 hours Difficulty: Hard 67% of papers passed

Performance is one of the most operationally relevant ATPL subjects. Recently, the focus has shifted from simply reading graphs to understanding the principles behind aircraft performance. There is significant overlap with Principles of Flight, and many ATOs teach them together to avoid duplication.

Graphs and tables are still part of the exam, but expect fewer piston-aircraft questions and more content based on modern jet transport operations.

For additional jet performance theory, the Airbus publication “Getting to Grips with Aircraft Performance” is a useful reference.

Approach this exam methodically. Clear thinking and careful graph interpretation are essential — especially when working through performance charts under time pressure.

Practise Performance questions

Explore key subtopics & core concepts of the Performance Syllabus