The Vacuum System and Gyroscopic Instruments

Question 1

How are most vaaccum systems powered?

Answer 1

Engine-driven suction pump

Question 2

How is the suction pump powered?

Answer 2

By the engine

Question 3

The suction pump powers what system?

Answer 3

Vacuum system

Question 4

What does a suction pump do?

Answer 4

Creates a vacuum in gyroscopic instruments

Question 5

How does a suction pump create a vacuum?

Answer 5

Evacuates the cases of instruments

Question 6

What creates a vacuum in gyros?

Answer 6

Suction pumps

Question 7

What is the first component in a vacuum system?

Answer 7

Air filter

Question 8

Where is the suction pump located in the vacuum system?

Answer 8

At the end

Question 9

What is located at the end of a vacuum system?

Answer 9

Suction pump

Question 10

What item immediately precedes the suction pump?

Answer 10

Vacuum relief valve

Question 11

What is the typical required suction?

Answer 11

3 to 5 inches of mercury

Question 12

What is the most common cause of a low suction gauge reading?

Answer 12

Blocked air filter

Question 13

What is the most common cause of a zero suction gauge reading??

Answer 13

Suction pump failure

Question 14

How are excessive vacuum pressures prevented?

Answer 14

Vacuum relief valve

Question 15

How does a venturi tube provide suction?

Answer 15

The low static pressure area in the venturi will cause higher pressure air in the instruments to flow to the tube

Question 16

An area of low static pressure drawing airflow from instruments describes what system?

Answer 16

Venturi tube vacuum system

Question 17

What is rigidity in space?

Answer 17

The ability for a rotating mass to maintain the same absolute direction in space

Question 18

The ability for a rotating mass to maintain the same absolute direction in space describes what?

Answer 18

Rigidity in space

Question 19

Gyroscopes have what crucial property?

Answer 19

Rigidiy in space

Question 20

As an aircraft moves ‘around’ a gyro, what happens to the gyro?

Answer 20

It remains stable in space

Question 21

What 3 factors affect the degree of rigidity in space of a gyroscope?

Answer 21

Mass of the rotor
Speed of rotation
Radius of mass

Question 22

What do these symptoms affect:
Mass of the rotor
Speed of rotation
Radius of mass

Answer 22

Rigidity in space

Question 23

What is the most optimal gryoscope in terms of directional rigidity?

Answer 23

Large mass concentrated at the rim rotating at high speed

Question 24

What is the secondary property of a gyroscope?

Answer 24

Precession

Question 25

The change in direction of a gyroscope if a force is applied to it is in what manner?

Answer 25

90 degrees further on to the direction of rotation

Question 26

Precession describes what kind of movement?

Answer 26

90 degrees further on to the direction of rotation

Question 27

When will a gryo under-read?

Answer 27

If rotation reduces

Question 28

If a gyro under-reads, what has happened to it?

Answer 28

Its rotation has reduced

Question 29

Precession's angle relationship to direction of applied force?

Answer 29

90 degrees

Question 30

What causes a slow drift in gyros?

Answer 30

Precession

Question 31

Precession is associated with what instrument phenomenon?

Answer 31

Gyro drift

Question 32

What risk may be associated with a vacuum pressure pump, as opposed to a vacuum suction pump?

Answer 32

A pressure pump would also pump contaminants such as oil into the gyroscopic instruments

Question 33

What kind of gyros do the turn indicator/coordinator use?

Answer 33

Rate gyros

Question 34

Rotation speed gives the gyro what property to resist tilting or turning?

Answer 34

Inertia

Question 35

What does inertia mean for a spinning gyro?

Answer 35

It can resist tilting or turning

Question 36

What allows gyros to hold their position while the instruments rotate around it?

Answer 36

Inertia

Question 37

Precession iis essentially the combination of what two forces?

Answer 37

Perpendicular to direction of force + direction of rotation

Question 38

What gyro instruments are vacuum powered?

Answer 38

Attitude Indicator and DI

Question 39

What gyro instruments are electrically powered?

Answer 39

Turn indicator/coordinator

Question 40

What does the Turn indicator/coordinator NOT show?

Answer 40

Bank angle

Question 41

What does the Turn indicator/coordinator show?

Answer 41

Rate of turn

Question 42

What will a turn coordinator show in addition to what a turn indicator shows?

Answer 42

Rate of bank

Question 43

A turn coordinator's 30-degrees angled gimbal means it provides reaction to what?

Answer 43

Rate of bank as well as just bank

Question 44

What returns the gimbal to the central position in a turn indicator?

Answer 44

Spring

Question 45

What does a spring do in a turn indicator?

Answer 45

Resists gimbal rotation

Question 46

What happens to a turn indicator when the aircraft stops turning?

Answer 46

Spring tension returns the gyro to its original position

Question 47

What kind of gyro is used in the attitude indicator?

Answer 47

Earth gyro

Question 48

An earth gyro is used for what instrument?

Answer 48

Attitude indicator

Question 49

What spin axis does an earth gyro have?

Answer 49

Vertical

Question 50

What spin axis does a rate gyro have?

Answer 50

Horizontal

Question 51

The pivoting components in a gyro are given what term?

Answer 51

Gimbals

Question 52

What do gimbals do in a gyro?

Answer 52

Pivot

Question 53

What term is given to the mechanical errors in DIs that will cause it to drift off accurate alignment with magnetic north?

Answer 53

Mechanical drift

Question 54

Mechanical drift in DIs are caused by what?

Answer 54

Friction

Question 55

Friction causes what in DIs?

Answer 55

Mechanical drift

Question 56

What term is given to the error in DIs that cause drift due to the aircraft's movement through space relative to north?

Answer 56

Apparent drift