slot

i. Fixed openings near the leading edge of the wing. At higher angles of attack, air from below the wing is guided through the slots and discharged over the upper surface, tangential to the wing surface, thereby re-energizing the boundary layer allowing a higher critical angle of attack. Slots are located ahead of ailerons and thus help maintain aileron control at lower speeds and at high angles of attack.

ii. The gap between the wing and the hinged trailing-edge surface (flap, aileron) through which air flows attached across the movable upper surface.

Air from the lower surface of the wing passes through it on to the upper surface of the aileron.

iii. A block of time allocated to an airport user to perform an aircraft operation (takeoff and landing) or for using a specific facility.

iv. The physical aperture of a slot aerial. See slot aerial.