16 Lift Augmentation

Question 1

Trailing Edge Flap

Answer 1

Increases CL but reduces Critical AOA.

CP moves aft so pitches the nose down.

Question 2

Split trailing edge flap

Answer 2

Split trailing edge - Increases CL and has a higher critical AOA compared to basic flap.
But produces a lot more drag.

Question 3

Fowler Flap

Answer 3

Fowler - Increases CL and the area of the wing for relatively small increase in drag.

Question 4

Slatted Fowler Flap

Answer 4

Increases CL and Surface area of the wing much the same as a fowler flap.

But also reduces form drag by increasing the speed of the air over the wing, making the boundary layer less prone to separation.

They also increase drag however by taking energy from below to give to the upper boundary.

Question 6

Krueger Flap

Answer 6

Krueger - Like variable camber it increases CL and Critical AOA.

Placed near wing root and with sharper leading edge, increases stall speed, encourages the wing to stall at the root.

Question 7

Variable Camber Flap

Answer 7

Variable Camber - increases CL and critical AOA.

The CP does not change and it provides a more rounded leading edge meaning the boundary layer is less prone to separation