Lesson 17 - High Lift Devices

What do trailing edge flaps change?

Wing camber (from TE)

What do leading edge flaps and slats change?

Wing camber (from LE)

What are strakes and LEX used for and what do they do?

• Low aspect ratio aircraft 

• Creates a vortex over the wing

What does boundary layer control do?

• Add or subtract flow to/from the boundary layer

• Active method of flow modification

• Complex (not used often)

What does powered lift / vectored thrust do?

• Redirect engine exhaust to augment lift

• Uses engine exhaust over flaps or direct from engine

What are the 6 different types of trailing edge flaps?

FBP SSS

• Basic

• Plain

• Slotted

• Fowler

• Split 

• Slotted fowler

What does the plain flap rotate about?

Rotates about trailing edge

Where do split flaps rotate?

Lower surface rotates

What do slotted flaps rotate about?

Rotate about TE and opens an air gap for air flow

What does a Fowler flap do?

Extends aft and rotates

Slotted Fowler Flap

Basic flap

What are the different kinds of leading edge flaps and slats?

• Fixed slot

• Leading edge slat

• Krueger flap

• Leading edge droop

Fixed Slot

Leading edge slat

Krueger flap

Leading edge droop

What does a leading edge slot do?

Allows flow through to add energy and helps to prevent separation

What does a leading edge slat do?

Variable slot, can open/close as needed

What does a leading flap do?

Adds camber to the airfoil

Do trailing edges have flaps and slats?

No, the trailing edge has flaps but not slats