Aerodynamics - motion and control

Question 1

Explain the three types of motion and the axes involved

Answer 1

Pitch - movement about the lateral axis (from wing end to wing end)
Roll - movement about the longitudinal axis, rolling left = left wing drops, rolling right = right wing drops
Yaw - movement about the normal axis

Question 2

What are the three primary flying controls

Answer 2

Elevator - initiates or prevents motion in the pitching plane
Ailerons - initiate of prevent motion in the rolling plane
Rudder - initiates or prevents motion in the yawing plane

Question 3

Engine torque

Answer 3

The tendency of the aircraft to rotate about its own crankshaft opposite to propeller rotation. This results in a roll to the left.

Question 4

What does the slipstream effect produce?

Answer 4

Produces a yaw.

Question 5

Aerofoils

Answer 5

Structures such as wings which are designed to generate lift from the passing airflow.

Question 6

Angle of attack

Answer 6

Angle formed between the relative airflow and the chord line of the wing.

Question 7

Relative airflow

Answer 7

An aircraft moving through the air experiences an apparent wind which always comes from the front, a result of the forward movement of the aircraft.

Question 8

Bank angle effect on load factor.

Answer 8

As bank angle increases load factor increases.

- 0 degree angle of bank is 1 (load factors produced)
- 30 degree angle of bank is 1.15
- 60 degree angle of bank is 2

Question 9

How to recover from large bank angle

Answer 9

Apply as much as full nose-down elevator.
Apply appropriate nose-down stabilizer trim.
Roll (adjust bank angle) to obtain a nose-down pitch rate.

Question 10

How is a spiral dive caused?

Answer 10

Spiral dive is a consequence of the yaw-roll relationship and can occur when an aircraft is allowed to roll with no further control inputs by the pilot. The sideslip resulting from the inclined lift produces a yaw in the direction of bank.

Question 11

How do you recover from a spiral dive?

Answer 11

Reduce power, gently level the wings and ease the nose up to the level flight attitude, reapply power.

Question 12

What is the difference between a spin and a spiral dive?

Answer 12

A spin differs from a spiral dive as neither wing is stalled during a spiral dive.

Question 13

Result of flap extension

Answer 13

Flap extension allows the use of smaller angles of attack at any given airspeed.