To ensure adequate maneuver margins, flight spoilers must not be extended in-flight at airspeeds below the recommended approach speed plus how many knots?

• A. 5 Knots
• B. 10 Knots
• C. 15 Knots
• D. 20 Knots

Answer: (B)

Extending flight spoilers reduces lift and increases drag. When you’re in the approach regime, you rely on the wing’s lift to maintain a stable glide path and enough roll authority in gusts or during maneuvering. If spoilers are used while the airplane is still below the recommended approach speed plus a buffer, the loss of lift can push you into a marginal flight condition, risking reduced control and a smaller stall margin. The ten-knot buffer above the approach speed gives a safety margin to account for weight changes, gusts, and pilot input, ensuring you have sufficient lift and control authority before deploying spoilers. Once you’re above that threshold, spoilers can be used without compromising maneuver margins.