# What is swept wing ? How does wing sweep affects aircraft performance ?

What is swept wing ? How does wing sweep affects aircraft performance ?

Asked on 14th July 2020 in

A swept wing is a wing that has an angle backward or forward. Most of the initial aircraft had a straight wing. There are many advantages of swept wing over a straight wing. By sweeping of wing, a wing sees an effectively smaller value of airflow velocity or Mach number. By sweeping the wings of a subsonic aircraft the drag divergence is delayed.

Swept wing with normal and tangential stream velocity components

If $$\Lambda$$ is the sweep angle of the swept wing than critical Mach number for an airfoil is less than actual critical Mach number for a swept wing which is less than critical Mach number for an airfoil/$$\cos\Lambda$$. Wing sweep increases the critical Mach number of the airfoil. However, wing sweep reduces the lift. There is a decrease in the coefficient of lift.

For a supersonic aircraft in a supersonic flight, wing sweep decreases the wave drag. A thin wing with a large angle of sweepback has the smallest wave drag.

Swept wing