Aircraft Wing Twist indicates the twist span of the wing. It helps in adjusting the lift distribution along the wing.
Types of Aircraft Wing Twist
- Geometric Twist
- Aerodynamic Twist
For aircraft with non-twisted wings, angle of attack is constant along the wingspan. If the angle of attack is not constant along the wing, it is known to be Geometric Twist.
There are two types of Geometric Twist –
- Washout – When the angle of attack at the tip is less than the angle of attack at root, it is known to be Washout Geometric Twist. Tip stalling needs to be minimised as it causes a high bending moment. To reduce the tip stalling, Washout Geometric Twist is used.
- Washin – When the angle of attack at the tip is greater than the angle of attack at root, it is known to be Washin Geometric Twist.
When the angle of attack at zero lift is not constant along the wing i.e. angle of attack at zero lift varies from root to tip, it is known to be the Aerodynamic Twist. Aerodynamic Twist basically affects the aerodynamic characteristics of the wing.