Why does the back of the wing on a commercial airliner extend out during landing procedures? What effect does it have on the aircraft?

Question

Why does the back of the wing on a commercial airliner extend out during landing procedures? What effect does it have on the aircraft?

In: Engineering

Answer 1

Those are called flaps. Flaps increase the lift produced by the plane’s wings at low speeds, which means the plane can take off and land at lower speeds (thus using less runway). Without flaps, at such low speeds, the plane might be too close to or even below its stall speed (meaning the plane stops flying and starts falling).