How do flaps affect stall, approach, and landing speeds?

• A. Flaps reduce stall speed but increase drag, enabling steeper approaches; they also alter Vref and Vapp per configuration.
• B. Flaps increase stall speed and reduce drag.
• C. Flaps do not affect Vref or Vapp.
• D. Flaps only affect V1.

Answer: (A)

Extending flaps increases wing camber and surface area, boosting lift at lower speeds. That lowers the stall speed in the landing configuration, so you can fly slower without stalling. The trade-off is a large increase in drag, which means you’ll need more thrust or energy management to maintain control and a stable approach, but you can still do a steeper approach if you keep the speed down safely.

Because stall speed changes with flap setting, the reference landing speed (Vref) and the approach speed (Vapp) also change with configuration. Vref is tied to the stall speed in the landing configuration, and Vapp is Vref plus margins, so both speeds are configuration dependent. Flaps therefore affect stall speed, drag, and the speeds used for approach and landing, not just a single speed like V1.