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Flashcards in Gyro Theory Deck (19):
1

Factors effecting gyro rigidity

Mass

Speed of rotation

Distribution of mass - furthest from the axis of rotation the more rigid

2

Gimbals

Allow the gyro to take up and hold its own orientation when the gimbals are moved around

3

Degree of freedom

Each axis on the gimbal excluding the spin axis

E.g 1 gimbal is added = introduced 1 additional rotation axis = 1 degree of freedom

4

If 2 gimbals are used

2 degrees of freedom introduced

Gyro can be moved around 3 planes without disturbing the gyro

5

2 planes of rotation

1 gimbal

1 degree of freedom

6

3 planes of rotation

2 gimbals

2 degrees of freedom

7

Gyro instruments

Direction indicator
Attitude indicator
Turn indicator

8

Gimbal lock

2 or more gimbals become aligned with each other which reduces the planes of rotation and the degrees of freedom

Common during acrobatics

9

Categories of gyro scope wander

Real

Apparent

10

Topple

The motion of axis in the vertical plane

Only occurs if the spinning axis is completely vertical

Dealt with by erection systems

11

Drift

Movement in the horizontal plane

Concern in navigation

12

Earths rotation speed at the poles

The earth rotates eastwards at 600kts and 15.04 degrees/hr

13

Vertical gyro at the equator

The observer will witness a topple by 90degrees every 6 hrs by either ER or TW

Max topple, no drift

Vertical will become horizontal

14

TW

Transport wander, to do with the movement of the gyro when the a/c travels across the earths surface

15

What will happen to the gyro when flying due north up a meridian from the equator

To an observer a vertical gyro will appear to topple backwards and become horizontal at the pole

It will also progressively drift

16

At the poles

Vertical gyros appear not to drift or topple

Horizontal gyros appear to drift

17

At the equator

Vertical gyros appear to topple

An east aligned horizontal gyro appears to topple backwards to the vertical

A north aligned horizontal gyro will neither topple or drift if it remains on the equator

18

Real wander

Happens in all gyros

Caused by bearing friction

19

The Latitude nut

Used to compensate for the ER at the a/c’s operational latitude

Small nut is adjusted which inputs a real wander effect to correct its position