Gyroscopes

Question 1

The two properties of a spinning gyro?

Answer 1

Rigidity and precession

Question 2

At what angle relative to the force will the gyro precess?

Answer 2

At right angles to the applied force, in the direction of gyro spin

Question 3

If the gyro wanders in the horizontal plane, it is called?

Answer 3

Drift

Question 4

If the gyro wanders in the vertical plane, it is called?

Answer 4

Topple

Question 5

Drift can either be?

Answer 5

real or apparent

Question 6

Topple can either be?

Answer 6

real or apparent

Question 7

Random mechanical forces (turbulence, asymmetric friction in the bearings and gimbals) can cause precession of a gyro, this is called?

Answer 7

Real wander

Question 8

What is apparent wander?

Answer 8

A gyro is set to a fixed point in space, not affected by earth’s rotation. The observer is obviously affected by earths rotation, so to the observer it will seem like the gyro is deviating from its fixed point. i.e wander

Question 9

A gyro is spinning around a shaft that is vertical, this a vertical or horizontal gyro?

Answer 9

The axis is vertical, so it’s a vertical oriented gyro.

Question 10

A horizontal axis gyro, at the equator aligned with E/W will have?

Answer 10

No drift

Maximum topple, 360 degrees of topple over 24 hours.

Question 11

A horizontal axis gyro, at the equator aligned with N/S will have?

Answer 11

No drift

No topple, will remain aligned with meridian over a 24 hour period.

Question 12

In the building principle of a gyroscope, the best efficiency is obtained through the concentration of the mass :

Answer 12

On the periphery and high rotation speed

Question 13

A horizontal axis gyro is at the north pole, after 6 hours what would occur to its apparent position?

Answer 13

It would appear to have drifted 90 degrees

Question 14

A horizontal axis gyro is at the equator, after 18 hours what would occur to its apparent position?

Answer 14

It would appeared to have toppled by 270 degrees

Question 15

The type of gyro a Directional indicator use?

Answer 15

Tied Gyro

Question 16

The type of gyro an Artificial Horizon use?

Answer 16

Earth Gyro

Question 17

The type of gyro a turn and slip indicator use, or turn co-ordinator, is?

Answer 17

Rate Gyro

Question 18

The tied gyro has freedom in?

Answer 18

Two planes

Question 19

The earth gyro has freedom in?

Answer 19

Two planes

Question 20

Due to the rotation of the Earth, the apparent drift of a horizontal free gyroscope at a latitude of 30°S is:

Answer 20

15 x sin(30) = 7.5

Question 21

Earth rate relevant to each hemisphere:

Earth rate formula:

Answer 21

Negative earth rate in NH

Positive in the SH

Earth rate = 15 x sin(lat) per hour

Question 22

Some gyros measure angles, e.g. 10° of pitch, 5° of bank, 30° of heading change, etc. These
are called ___________ gyros. Others measure angular rate, e.g. a turn rate of 3° per second.
These are called ___ gyros.

Answer 22

Some gyros measure angles, e.g. 10° of pitch, 5° of bank, 30° of heading change, etc. These
are called displacement gyros. Others measure angular rate, e.g. a turn rate of 3° per second.
These are called rate gyros.

Question 23

Displacement gyros have 2 gimbals and 2 degrees of freedom. Examples are the __ and the __. Rate gyros have one gimbal and one degree of freedom and are used in the ___ ___ ___ ______ and in ___ dampers.

Answer 23

Displacement gyros have 2 gimbals and 2 degrees of freedom. Examples are the Directional 
Gyro Indicator (DGI) and the Artificial Horizon. Rate gyros have one gimbal and one degree 
of freedom and are used in the Rate of Turn Indicator and in yaw dampers.

Question 24

Drift clockwise or anti-clockwise:

NH:

SH:

Answer 24

NH decrease(clockwise)

SH increase(counter-clockwise)