Lower the slit flap. On the one hand, a gap is formed between the leading edge of the flap and the trailing edge of the wing. Speeding up, increasing energy, delaying the separation of air flow, and increasing the lift coefficient; on the other hand, lowering the opening flaps increases the wing camber, which also has the effect of increasing the height. The lift coefficient can generally increase by 85% to 95%, but the critical angle of attack does not decrease much. Slotted flaps usually have 1 to 3 slits.