Stability

Question 1

Longitudinal stability is

Answer 1

The stability of an ac in the elevator sense

Question 2

In longitudinal stability if the CG is moved forward

Answer 2

Longitudinal Stability increases - bigger moment atm in the tail plane arm as there is a bigger distance covered

Question 3

In longitudinal stability the wing arm is known as the

Answer 3

Destabilising arm

Question 4

Neutral longitudinal static stability

Answer 4

CG on the neutral point

Question 5

Forward CG limit (longitudinal stability)

Answer 5

Gives max stability and guarantees minimum acceptable manoeuvrability and maximum acceptable stick forces

Question 6

Aft CG Limit

Answer 6

Gives min stability , max manoeuvrability and min acceptable stick forces

Question 7

Longitudinal static stability

Answer 7

Is the initial reaction to a change in angle of attack

Question 8

The more forward the CG

Answer 8

The less manoeuvrable the AC is and the more stable it is

Question 9

Effect of wing down wash on stability

Answer 9

Negative - Tailplane AoA increases and thus the pitching moment

Question 10

Underslung engines

Answer 10

Create a nose up pitching moment so elevator deflection should be down

Question 11

40% MAC in regards to CG position

Answer 11

Is known as the neutral point

Question 12

When IAS increases a ____ force is required and when IAS decreases a _____ force is required
(Stick force)

Answer 12

Push , pull

Question 13

A statically stable ac

Answer 13

Can show positive , neutral or negative dynamic longitudinal stability

Question 14

What factors can pilots influence in flight

Answer 14

Centre of pressure points ! Not centre of gravity

Question 15

Static stick force stability - how to recognise static stick force stability in flight

Answer 15

BeLow- pull
aboVe- pVsh

Question 16

If CG moves aft

Answer 16

Stick force stability decreases