Aerodynamics

Question 1

What are the four forces of flight

Answer 1

Lift
Weight
Thrust
Drag

Question 2

Describe Lift

Answer 2

Lift is generated by Bernoulli’s principal and Newtons 3rd Law.

Bernoulli: As air passes above and below the wing, which is acting as an airfoil, it makes low pressure zones above the wing and high pressure zones below the wing.

Newton: For every action, there is an equal and opposite reaction. When angle of attack increases, air deflects off the lower surface and is felt as lift on the higher surface.

Can be increased by increasing angle of attack and velocity.

Question 3

Describe Angle of Attack

Answer 3

The angle between the chord line and the relative wind

Question 4

Describe Critical Angle of Attack

Answer 4

Beyond the max angle of attack, causing a stall

Question 5

How do you recover from a stall?

Answer 5

You let the nose fall (decreasing AoA) to regain lift.
Add full power.
Pitch for Attitude that increases altitude and speed.
Use Rudder for wing drops.

Question 6

What are the Stages of a Spin? EIDR

Answer 6

Entry
Incipient
Developed
Recovery

Question 7

How do you recover from a spin? PARE

Answer 7

Power idle
Ailerons Neutral
Rudder full opposite of the direction of the spin
Elevator briskly forward.

Question 8

What are the 4 left turning tendencies?

Answer 8

Torque
P-Factor
Spiraling Slipstream
Gyroscopic Precession

Question 9

Define the left turning tendency caused by Torque.

Answer 9

This is caused by the rotation of the propeller and crankshaft spinning to the right, which is felt as torque from the left.

Question 10

Define the left turning tendency caused by P-Factor.

Answer 10

The descending propeller blade takes a larger ‘bite’ out of the air at higher AoA on the right side, increasing thrust from the right, turning the plane left

Question 11

Define the left turning tendency caused by Spiraling Slipstream

Answer 11

The wind created from the prop spirals around the airplane and hits the left side of the tail, causing the airplane to turn left

Question 12

Define the left turning tendency caused by Gyroscopic Precession

Answer 12

The force on the prop, which acts a gyro, is felt 90 degrees in the direction of rotation

Question 13

Describe Load Factor

Answer 13

The vertical component of lift being transferred to the horizontal component when we are in a deep bank. As we bank, we need to increase elevator to keep the vertical left and this adds pressure to the wings.
Stall speed is increased while in a bank.