SS&C-2

Question 1

What are the assumptions made regarding geometry and inertia?

Answer 1

1. Rigid body
2. Constant mass distribution –> Inertial properties are therefore constant.

Lect. 24, S2

Question 2

What are the assumptions made regarding the motion of the aircraft?

Answer 2

1. The CG translates in space due to the net forces acting on the CG
2. The body rotates about the CG to due applied net moments.

Lect. 24, S2

Question 3

What assumption is made regarding static stability analysis in terms of the equations of motion?

Answer 3

The aircraft is a non-accelerating body.

Lect. 24, S2

Question 4

What are the two primary objectives of Longitudinal static stability?

Answer 4

1. The aircraft must possess characteristics that allow it to be trimmed.
2. Positive static stability.

Lect. 24, S3

Question 5

If the aircraft is trimmed, moments about the ___ are ____.

Answer 5

CG
zero

Lect. 24, S3

Question 6

How do downwash and viscous flow affect the wings?

Answer 6

Downwash changes the velocity angle.
Viscous flow slows down the airflow over the wings and reduces the effective lift.

Lect. 24, S5

Question 7

True or False

For static stability, C_M_alpha must be less than zero.

Answer 7

True

Lect. 24, S15

Question 8

True or False

For static stability, C_M_CL must be greater than zero.

Answer 8

False. C_M_CL must be less than zero.

Lect. 24, S15

Question 9

True or False

For static stability, C_M_0 must be greater than zero.

Answer 9

True

Lect. 24, S15

Question 10

A high wing is _______, while a low wing is _______.

Answer 10

Stabilizing
De-stabilizing

Lect. 24, S20