Definition
Movable surfaces or systems on a wing — most commonly flaps and slats — that temporarily increase the wing's lift at low airspeeds. They work by changing the wing's shape, its area, or the airflow over it, allowing the airplane to fly safely at slower speeds during takeoff and landing.
Plain English
Parts of the wing that can be extended to help the airplane keep flying at slower speeds, especially when taking off or landing.
Context Anchor
Seen in stall discussions, takeoff and landing procedures, and any checklist or system description involving flaps, slats, or other wing devices used for low-speed flight.
Derivation
Plainly named for what they do: produce 'high lift' on demand. The label is a category — a bucket that holds flaps, slats, leading-edge cuffs, and similar devices — rather than a single part.
Why Pilots Care
They allow slower approach and takeoff speeds, shorter runway distances, and better control near the stall boundary.
Intuition Check
Do not read “high-lift” as meaning the airplane will automatically climb better. It means the wing is being helped to produce more lift, often so the airplane can fly safely at a slower speed.
Example Sentence 1
Before turning final, the pilot extended the flaps — the airplane's high-lift devices — to slow the approach speed and steepen the descent.
Example Sentence 2
High-lift devices are retracted after takeoff once the airplane has gained sufficient speed and altitude.