Definition
High-lift attachments mounted on the leading edge (front edge) of the wing — such as slats, slots, leading edge flaps, and Krueger flaps — that increase the lift produced at low airspeeds and high angles of attack, allowing the airplane to fly slower without stalling.
Plain English
Movable or fixed parts on the front edge of the wing that help the wing keep flying at slow speeds, especially during takeoff and landing.
Context Anchor
Seen in discussions of takeoffs, landings, slow flight, stalls, and airplane wing design.
Derivation
Leading edge' is the front edge of the wing — the edge that 'leads' into the oncoming air. 'Devices' simply means the mechanical parts attached there. The name describes their location.
Why Pilots Care
They enable safe operation at lower speeds, shorten required runway lengths, and reduce stall speed without compromising cruise performance.
Grounding Statement
When the airplane is slow, leading edge devices help the wing keep smooth airflow over it instead of losing lift too early.
Intuition Check
Do not read “leading edge” as meaning “advanced” or “cutting-edge.” Here it means the physical front edge of the wing, where the air meets the wing first.
Example Sentence 1
As the airspeed slowed on approach, the leading edge devices extended automatically to help maintain lift.
Example Sentence 2
On final approach the airplane's leading edge devices remained extended to maintain aileron effectiveness as airspeed decreased.