Definition
A wing design feature in which the wings angle rearward from the fuselage rather than extending straight out perpendicular to it. Sweepback delays the onset of compressibility effects at high speeds and contributes to directional stability by causing the rearward wing to produce more lift than the forward wing during a yaw, which helps return the aircraft to coordinated flight.
Plain English
The wings are angled backward from where they meet the body of the aircraft, rather than sticking straight out to the sides. This shape helps the airplane handle high speeds better and naturally tends to keep it pointed in the right direction.
Context Anchor
Seen in aircraft design and performance discussions, especially when comparing straight-wing airplanes with swept-wing airplanes.
Derivation
From 'sweep' (a long, curved motion backward) and 'back.' The wings appear to have been swept rearward from a straight position, which describes both the look and the design intent.
Why Pilots Care
Controls drag rise and delays compressibility effects at high speeds, directly affecting cruise efficiency and handling.
Grounding Statement
Picture looking down at an airplane from above: if each wing angles backward toward the tail, the wing has sweepback.
Intuition Check
Sweepback does not mean the wing tilts upward or downward. It means the wing angles backward when viewed from above.
Example Sentence 1
The aircraft's sweepback allows it to cruise efficiently at high subsonic speeds without encountering severe compressibility effects.
Example Sentence 2
Moderate sweepback on the airliner improved stability without harming low-speed takeoff performance.