PPL Principals of Flight 02

Static and dynamic stability

1 / 21

What is the difference between static and dynamic stability?

2 / 21

If an aeroplane exhibits positive dynamic stability, what is correct in terms of static stability?

3 / 21

When does an aeroplane exhibit positive static stability?

4 / 21

What does positive static stability mean?

5 / 21

When does an aeroplane display neutral static stability?

6 / 21

When is neutral dynamic stability experienced?

7 / 21

What does negative static stability mean?

8 / 21

When does an aeroplane display negative static stability?

9 / 21

When would the aeroplane display negative dynamic stability?

10 / 21

What does the term 'equilibrium' mean?

11 / 21

What does the term 'equilibrium' mean practically?

12 / 21

What does the term "equilibrium of forces" practically mean in straight and level flight?

13 / 21

If the center of gravity is in front of the center of pressure of an airfoil, what moment is generated by the wing?

14 / 21

If the center of gravity is aft of the center of pressure of an airfoil, what moment is generated by the wing?

15 / 21

How can we balance a reduced pitch-up moment generated by the wings?

16 / 21

How can longitudinal equilibrium be achieved if the center of pressure coincides with the center of gravity?

17 / 21

How can the pilot reach longitudinal equilibrium other than moving a deflectable control surface?

18 / 21

How can longitudinal equilibrium be achieved if the center of pressure does not coincide with the center of gravity?

19 / 21

The AoA (angle of attack) was reduced in straight and level flight, how can we increase it back to the original AoA?

20 / 21

How can an increased pitch-up moment generated by the wing be balanced?

21 / 21

Why must the CG of the aeroplane be carefully calculated to fall between the limits?

Static and dynamic longitudinal stability

1 / 11

What is the stability around the lateral axis called?

2 / 11

What is the most important influencing factor of static longitudinal stability from the following list?

3 / 11

What does a forward center of gravity (CG) mean?

4 / 11

Which of the following statements about the center of gravity (CG) margin is correct?

5 / 11

How does the aircraft become more stable in terms of static longitudinal stability?

6 / 11

An aeroplane exhibits positive static longitudinal stability. If after having encountered a pitch up moment change, what moment does it generate?

7 / 11

An aeroplane exhibits negative static longitudinal stability If after entering an upward gust, what moment does it generate?

8 / 11

If the CG is in front of the forward limit, which of the following statements is correct?

9 / 11

What does an aft CG position mean?

10 / 11

If the CG is situated aft of the aft limit, then:

11 / 11

Why is its dangerous if the CG falls aft of the aft limit?

Lateral and Directional stability

1 / 6

What is the stability around the longitudinal axis called?

2 / 6

What is the stability around the vertical axis called?

3 / 6

If the static directional stability is too high compared to static lateral stability, the aeroplane is prone to:

4 / 6

What are the symptoms of a "spiral dive"?

5 / 6

What does a spiral dive result from?

6 / 6

How do you recover from a spiral dive?