POF - Lift

The upward movement of air at the LEADING edge is known as:

• The total reaction

• Upwash

• Downwash

• Leftwash

The point at the leading edge where air comes to a complete stop is know as:

• The stop point

• The stationary point

• The stagnation point

• The zero speed point

For a general purpose aerofoil the AoA for zero lift is:

• 4° AoA

• 0° AoA

• -4° AoA

• -6° AoA

At the zero lift angle:

• Negative lift is produced

• A small amount of lift is produced

• The aircraft will stall

• No net lift is produced

For a general purpose aerofoil what is the critical angle and what happens if it is exceeded

• 16°, the aircraft will stall

• 18°, the aircraft will fly backwards

• 16°, the amount of life will continue to increase

• 18°, the aircraft will stall

Which of the these pressure envelopes represents an aerofoil at the critical angle (16°)

• A

• B

• C

• D

Centre of Pressure:

• Is the point where weight acts through

• Is the point where upwash acts through

• Is the point downwash acts through

• Is the point lift acts through

What happens to the total reaction with an increase in AoA

• Decreases and tilts forwards

• Increases and tilts forwards

• Decreases and tilts backwards

• Increases and tilts backwards

Which attributes would be considered an ideal aerofoil?

Select all that apply

• High Max CL

• Low Minimum Cd

• Low Lift/Drag ratio

• Large and stable movement of CoP

• Sufficient Depth

Lift is:

• The component of the total reaction acting inline with the RAF

• The component of drag caused by friciton

• The component of the total reaction acting inline with the RAF in the direction of motion

• The component of the total reaction acting 90° to the RAF through the CoP