Stability

Question 1

The contribution of the wing to the static longitudinal stability of an aeroplane: depends on CG location relative to the wing ___ ____.

Answer 1

aerodynamic centre.

Question 2

Long period oscillations involves slow changes in altitude and ___.

Answer 2

speed

Question 3

The stick force gradient is the force required to change the __ ___ of the aircraft a given amount

Answer 3

load factor

Question 4

A negative contribution to the static longitudinal stability of conventional jet transport aeroplanes is provided by:

a) the fuselage
b) the tail

Answer 4

a) the fuselage

Question 5

A high limit load factor enables the manufacturer to design for a __ stick force per g.

Answer 5

lower

Question 6

The purpose of the horizontal stabilizer is to give the aeroplane sufficient longitudinal ___.

Answer 6

stabilty

Question 7

An aeroplane is longitudinally stable. When the angle of attack increases the change in total aeroplane lift acts __ of the CG.

Answer 7

aft

Question 8

If a stick force of 20 lbs is required to pull 3g from the position of trim, the stick force gradient is __ lbs/g

Answer 8

10

þetta g er “gee’s” ekki “grams”. Þú ert nú þegar með 1G og ertu að skoða m.v. 2g sem er aukningin

Question 9

Hvað gerist fyrir stick force stability og manoeuvre stability ef þú setur CG fram?

Answer 9

aukast bæði.

Question 10

Hvernig breytist stick force per G með hæð?

Answer 10

breytist ekki

Question 11

What effect does an elevator trim tab have on static longitudinal stability?

Answer 11

no effect

Question 12

What is correct:

a) A short period oscillation should always be heavily dampened
b) Aeroplanes can easily cope with slightly unstable short period oscillations

Answer 12

a) A short period oscillation should always be heavily dampened

Question 13

Hvað gerist ef þú færir CG fyrir aftan neutral point?

Answer 13

Vél verður longitudinally unstable

Question 14

An aeroplane with CG behind the CP can only maintain straight and horizontal flight when the horizontal tail loading is a) upwards b) upwards or downwards depending on elevator deflection

Answer 14

a) upwards

Question 15

Increasing the size of the fin

a) increases directional stability
b) increases lateral stability

Answer 15

a) increases directional stability

Question 16

Which statement concerning sweep back is correct?

a) sweep back is mainly intended to increase static directional stability
b) sweep back provides a positive contribution to static lateral stability

Answer 16

b) sweep back provides a positive contribution to static lateral stability

Question 17

Sweep back of a wing positively influences

a) static longitudinal stability
b) static lateral stability
c) dynamic longitudinal stability

Answer 17

b) static lateral stability

Question 18

Positive static lateral stability is the tendency of the airplane to

a) roll to the left in case of a sideslip (with the airplane nose pointing to the left of the incoming flow).
b) roll to the left in a right turn

Answer 18

a) roll to the left in case of a sideslip (with the airplane nose pointing to the left of the incoming flow).
Held að þetta eigi ekki við í venjulegum beygjum því að þetta er svolítið öfugsnúið eitthvað.

Question 19

Lateral static stability is determined by:

a) aircraft response to sideslip
b) wingspan

Answer 19

a) aircraft response to sideslip

Question 20

Static lateral stability should not be too small because

a) the aeroplane would show too strong tendency to dutch roll
b) the aeroplane would show too strong a tendency to spiral dive

Answer 20

b) the aeroplane would show too strong a tendency to spiral dive

Question 21

An example of a combined lateral and directional aperiodic motion is a:
a) spiral dive b) Dutch roll

Answer 21

a) spiral dive

Question 22

One advantage of mounting the horizontal tailplane on top of the vertical plane is to:

a) Decrease the susceptibility of a deep stall
b) improve the aerodynamic efficiency of the vertical fin

Answer 22

b) improve the aerodynamic efficiency of the vertical fin