CPL Flight Performance and Planning 3 — Questions and Answers
Question 1: What is the significance of V1 (takeoff decision speed) during a multi-engine takeoff?
- The speed at which the aircraft becomes airborne
- The maximum speed at which the pilot can abort the takeoff and stop within the available runway (Correct answer)
- The rotation speed for normal takeoffs
- The speed at which gear must be retracted
Correct answer: The maximum speed at which the pilot can abort the takeoff and stop within the available runway
V1 is the critical engine failure recognition speed; at or above V1, the pilot must continue the takeoff because stopping within the remaining runway is no longer assured.
Question 2: For FAR Part 135 operations, what is the IFR alternate airport fuel requirement?
- Fuel to destination plus 30 minutes at cruise
- Fuel to destination plus fuel to alternate plus 45 minutes at cruise (Correct answer)
- Fuel to destination plus 2 hours at cruise
- Fuel to alternate plus 30 minutes only
Correct answer: Fuel to destination plus fuel to alternate plus 45 minutes at cruise
FAR 135.209 requires fuel to fly to the destination, then to the alternate, plus 45 minutes of cruise flight at normal fuel consumption.
Question 3: What is the 'accelerate-stop distance' (ASD)?
- The distance required to accelerate to V2 and climb to 35 feet
- The total distance needed to accelerate to V1, experience an engine failure, and stop completely (Correct answer)
- The runway distance used from brake release to liftoff
- The distance from liftoff to reaching obstacle clearance altitude
Correct answer: The total distance needed to accelerate to V1, experience an engine failure, and stop completely
Accelerate-stop distance is the total runway required to accelerate to V1, recognize an engine failure, and brake to a full stop.
Question 4: A pilot is planning a flight at 10,000 ft MSL and the outside air temperature is +10°C. Standard temperature at 10,000 ft is -5°C. What is the density altitude?
- 10,000 ft
- Approximately 12,700 ft (Correct answer)
- Approximately 7,300 ft
- Approximately 10,900 ft
Correct answer: Approximately 12,700 ft
With OAT 15°C above standard, density altitude is approximately 10,000 + (15 × 120) = ~11,800–12,700 ft depending on correction formula used.
Question 5: What is meant by 'balanced field length'?
- A runway where the length equals width
- The condition where accelerate-stop distance equals accelerate-go distance (Correct answer)
- A runway with equal upslope and downslope sections
- The runway length required for a normal takeoff at gross weight
Correct answer: The condition where accelerate-stop distance equals accelerate-go distance
Balanced field length is achieved when the accelerate-stop distance equals the takeoff distance following an engine failure at V1, optimizing use of the available runway.
Question 6: How does a downhill runway slope affect takeoff performance?
- Increases ground roll distance
- Decreases ground roll distance (Correct answer)
- Has no effect on ground roll
- Reduces liftoff airspeed
Correct answer: Decreases ground roll distance
A downhill slope allows the aircraft to accelerate faster due to the gravitational component aiding forward motion, reducing the ground roll required.
Question 7: What is the purpose of the 'obstacle clearance limit' in takeoff planning?
- To establish the minimum runway required for departure
- To ensure the aircraft can clear all obstacles in the departure path with a required gradient (Correct answer)
- To define the maximum allowable takeoff weight for the aircraft type
- To calculate the climb gradient needed for IFR departure procedures
Correct answer: To ensure the aircraft can clear all obstacles in the departure path with a required gradient
Obstacle clearance limits ensure that following an engine failure at V1, the aircraft can clear all obstacles along the departure flight path with the required safety gradient.
CPL Flight Performance and Planning 3
What is the significance of V1 (takeoff decision speed) during a multi-engine takeoff?