Definition
A wing planform in which the chord (the distance from the leading edge to the trailing edge) decreases gradually from the wing root to the wing tip, producing a wing that is wider where it joins the fuselage and narrower at the tip, but without an extreme reduction in width.
Plain English
A wing that is wider where it meets the fuselage and gets gradually narrower toward the tip, but not dramatically so. It sits between a fully rectangular wing and a sharply pointed one.
Context Anchor
Seen when studying wing shapes and how the outline of a wing affects lift, drag, structure, and stall behavior.
Derivation
‘Taper’ comes from the Old English ‘tapor,’ meaning to grow narrower toward one end — like a candle. ‘Moderate’ simply means not extreme. So a moderate taper wing narrows toward the tip, but only gradually.
Why Pilots Care
Provides a good compromise between efficient lift distribution, manageable stall behavior, and reasonable structural weight.
Grounding Statement
Picture a wing that is broad near the airplane body and slowly narrows as it reaches the tip.
Intuition Check
Moderate does not mean the wing is only somewhat important. It means the amount of narrowing is limited. Taper does not mean the wing is thinner from top to bottom. Here it means the wing gets narrower when viewed from above.
Example Sentence 1
Many general aviation trainers use a moderate taper wing because it balances efficiency with gentle stall behavior.
Example Sentence 2
Designers selected a moderate taper wing to reduce induced drag while keeping roll response comfortable for student pilots.