FAA Flight Instructor Airplane (FIA)Performance, Weight and BalanceEasy
An airplane's POH states that takeoff ground roll decreases by 10% for each 9 knots of headwind component. The no-wind takeoff ground roll is 1,200 ft, and the reported headwind component is 9 knots. What is the corrected takeoff ground roll?
- A1,200 ft
- B960 ft
- C1,080 ft
- D1,320 ft
Show answer & explanationAnswer & explanation
Correct answer: C. 1,080 ft
A 9-knot headwind reduces distance by 10%: 1,200 ft × 0.10 = 120 ft reduction. 1,200 − 120 = 1,080 ft.
Why the other options are wrong
- A. Ignores the headwind correction entirely.
- B. Represents a 20% reduction, double the correct adjustment.
- D. Incorrectly increases distance instead of decreasing it.
Headwind Effect on Takeoff Distance
A headwind reduces groundspeed at liftoff, shortening the ground roll; POH charts typically express this as a percentage reduction per knot increment of headwind.
- Headwind shortens takeoff and landing distance
- Correction is often stated per specific knot increment (e.g., 9 kt = 10%)
- Always use the headwind COMPONENT, not full wind speed
- Tailwind has the opposite, and larger, effect
Memory trick: 'Headwind helps, tailwind terrorizes' distance.