The Artificial Horizon

Question 1

What type of gyro does the AH use?

Answer 1

Earth gyro

Question 2

In what axis is the AH gyro?

Answer 2

Vertical axis gyro

Question 3

When considering the artificial horizon, the freedom of rotation about the lateral axis, inner gimbal, is how much?

Answer 3

55 degrees either side of the horizon

Question 4

When the aircraft initiates bank, what are the movements of the inner and outer gimbals?

Answer 4

No movement, the inner and outer gimbals remain fixed to the true horizontal/vertical. Only the instrument case, the angle of bank scale and the miniature aircraft rotate about the aircraft’s longitudinal axis.

Question 5

Movement of the outer gimbal indicates?

Answer 5

Roll

Question 6

Movement of the inner gimbal indicates?

Answer 6

Pitch

Question 7

Pendulous error during acceleration will result in a false?

Answer 7

Right bank indication

Question 8

Pendulous error during deceleration will result in a false?

Answer 8

Left bank indication

Question 9

Erection error during deceleration will result in a false?

Answer 9

Descent indication

Question 10

RPM of the electrical artificial horizon?

Answer 10

22 000rpm

Question 11

The electrical artificial horizon is held to the true vertical by?

Answer 11

torque motors controlled by mercury levelling switches

Question 12

During a 360 degree turn, at what point will turning error be maximum?

Answer 12

At 180 degrees into the turn, thereafter reducing to zero

Question 13

The RPM of a suction AH?

Answer 13

15 000 RPM

Question 14

AH turning errors:

Turning through 90°:

Turning through 180°:

Turning through 270°:

Turning through 360°:

Answer 14

AH turning errors:

Turning through 90°: Under reads bank angle; Pitch error – indicating a climb

Turning through 180°: Bank angle correct; Pitch error – indicating a climb (maximum pitch up error)

Turning through 270°: Over reads bank angle; Pitch error – indicating a climb

Turning through 360°: Bank angle correct; Pitch correct

Question 15

The layout of the vanes viewed from above, and the direction rotation of the gyro?

Answer 15

Top and bottom vanes are to the right, left vane at the top and right vanes and the bottom.

Anti-clockwise

Question 15

Erection error during acceleration will indicate:

Answer 15

A false climb

Question 16

Air-driven AH gyro: kept in the vertical by

Electrical AH gyro: kept in the vertical by

Answer 16

pendulous vanes/air jets

two mercury switches sending signals to torque motors

Question 17

The attitude display consists of a miniature aircraft shape or ‘gull-wing’ (tail view) painted or
engraved centrally on the inside of the glass face of the instrument, and therefore fixed to the instrument case and the -

Behind this representation of the aircraft is the horizon bar, linked to the gyro in such a way that the bar is gyro-stabilized parallel to the -

Answer 17

actual aircraft

True horizon

Question 18

With older designs, typical limits are ± __° in pitch and ___° each way in roll.

In modern instruments there is _______ freedom in roll and up to __° (plus or minus) in pitch

Answer 18

With older
designs, typical limits are ± 60° in pitch and 110° each way in roll.

In modern instruments
there is complete freedom in roll and up to 85° (plus or minus) in pitch

Question 19

During normal coordinated turns, what error due to precession should you observe when rolling out to straight and level flight from a 180° steep turn to the right?

A
The miniature aircraft would show a slight descent and wings level attitude

B
A straight and level coordinated flight indication

C
The miniature aircraft would show a slight turn indication to the left

Answer 19

C

The miniature aircraft would show a slight turn indication to the left

Question 20

The characteristics of the gyroscope used in a gyromagnetic compass system are:

A
one degree of freedom, whose axis is maintained in the direction of the local vertical by an erecting system

B
two degrees of freedom, whose axis is maintained in the direction of the local vertical by an erecting system

C
two degrees of freedom, whose horizontal axis corresponding to the reference direction is maintained in the horizontal plane by an erecting system

D
one degree of freedom, whose horizontal axis is maintained in the horizontal plane by an erecting system

Answer 20

C
two degrees of freedom, whose horizontal axis corresponding to the reference direction is maintained in the horizontal plane by an erecting system

Question 21

The heading read on the dial of a directional gyro is subject to errors, one of which is due to the movement of the aircraft. This error…

A
is dependent on the ground speed of the aircraft, its true track and the latitude of the flight

B
is at its greatest value when the aircraft follows a meridional track

C
shows itself by an apparent rotation of the horizontal axis of the gyroscope which seems to turn at 15° per hour to the right in the northern hemisphere

D
is, in spite of this, insignificant and may be neglected

Answer 21

A

is dependent on the ground speed of the aircraft, its true track and the latitude of the flight

Question 22

The heading read on the dial of a directional gyro is subject to errors, one of which is due to the movement of the aircraft. This error…

A
is dependent on the ground speed of the aircraft, its true track and the latitude of the flight

B
is at its greatest value when the aircraft follows a meridional track

C
shows itself by an apparent rotation of the horizontal axis of the gyroscope which seems to turn at 15° per hour to the right in the northern hemisphere

D
is, in spite of this, insignificant and may be neglected

Answer 22

A

is dependent on the ground speed of the aircraft, its true track and the latitude of the flight

Question 23

The flux valve of a gyromagnetic compass:

1 - feeds the error detector

2 - feeds the direct indicating compass

3 - gives the earth’s magnetic field direction

The combination regrouping all of the correct statements is:

A
1, 3

B
2, 3

C
3

D
1, 2

Answer 23

A
1, 3

Remember FEAT