Which flap setting is utilized for shorter than normal landing distances and assists in braking through runway surface contaminants?

The choice of using 50% flaps for shorter than normal landing distances is based on the aerodynamic benefits they provide during landing. When the flaps are extended to this setting, it increases lift while also allowing for a slower approach speed. This configuration helps the aircraft to maintain better control and stability as it descends towards the runway.

Furthermore, deploying flaps assists in achieving a steeper angle of descent without exceeding safe airspeed limits, which can be particularly beneficial when dealing with contaminants on the runway surface, such as ice, snow, or rain. The increased lift and drag from the flaps enable the aircraft to land more decisively and apply brakes more effectively, enhancing overall stopping performance.

In contrast, using 0% flaps would not provide the additional lift needed for a shorter landing distance, and would likely result in a longer landing roll due to less drag and a higher approach speed. A setting of 100% flaps, while it does create more drag and lift, may be excessive in some conditions and could lead to operational complexities during the landing process. The term "approach speed" is not a flap setting but rather the speed at which the aircraft is flown during the final approach, making it an inappropriate choice when discussing flap