Systems 2

Question 1

Which aircraft systems utilise hydraulics?

Answer 1

Flying controls
Undercarriage
Brakes and steering
Ramp
Winch

Question 2

Why are back up hydraulic systems necessary?

Answer 2

Redundancy

Question 3

Name the components in the hydraulic system (diagram)

Answer 3

Filter
Accumulator
Reservoir
Actuator
Pump

Question 4

Filter Purpose

Answer 4

Debris removal

Question 5

Accumulator

Answer 5

Nitrogen charged damper

Question 6

Reservoir

Answer 6

Incompressible fluid

Question 7

Actuator

Answer 7

Hydraulic to mechanical power

Question 8

Pump

Answer 8

Rotary swash plate

Question 9

What are the advantages of hydraulics?

Answer 9

Incompressible
Capable of transmitting very high forces
Rapid and precise response to input signals
Good power to weight ratio
Simple and reliable
Not affected by electromagnetic interference

Question 10

What effect would the following have on a hydraulic system?
High pressure
Low pressure
Low contents

Answer 10

High pressure:
Gas generated making the fluid/gas mixture compressible
Low pressure:
Poor force multiplication
Low contents:

Question 11

How can aircraft undercarriage be lowered in an emergency?

Answer 11

Blow down
Hand pump

Question 12

What are aircraft brake disks made of and why?

Answer 12

Carbon composites which are able to operate at the necessary temperatures

Question 13

What prevents the undercarriage extending under high G loading?

Answer 13

Uplock

Question 14

What is the sequence of undercarriage extension?

Answer 14

Unlock - disengage
Fairing - open
Actuator - extend
Down lock - engage

Question 15

See aircraft undercarriage system lights

Question 16

What are the electrical sources?

Answer 16

Primary:
Batteries (24v)
AC Generators (200v, 3 Phase, 400Hz)
DC Generator
Auxiliary:
Auxiliary Power Unit (APU)
Ground Power Unit (GPU)
Emergency:
Batteries

Question 17

Name the highlighted components, see diagram.

Answer 17

Excited field
Excited armature
Main field
Main armature
Power distribution circuit

Question 18

Function of the following:
Transformer/Rectifier Unit
Converter
Inverter
Circuit Breakers (CBs)
RCCOs

Answer 18

Transformer/Rectifier Unit:
Convert AC to DC
Converter:
Change the frequency of AC
Inverter:
Convert DC to AC
Circuit Breakers (CBs):
Fuse
RCCOs:
Reverse current cut out, prevents the generator drawing from the battery

Question 19

What are the three types of consumer services?

Answer 19

Vital services:
Required after an emergency landing or crash
Essential services:
Required to ensure safe flight in an emergency
Non-essential services:
May be shed in an emergency

Question 20

What effect does connecting external power have on the battery contactor?

Answer 20

Deactivated

Question 21

What is the purpose of the following:
Voltage regulator
Constant speed drive unit
Integrated drive generator

Answer 21

Voltage regulator:
Sample the output voltage and adjust the current fed into the generators main exciter field coils
Constant speed drive unit:
Maintains a constant generator RPM
Integrated drive generator:
Generator with an integrated CSDU

Question 22

How are AC generators automatically balanced?

Answer 22

Synchronisation of voltage, frequency and phase angle

Question 23

What are the indicators and components associated with the CWS?

Answer 23

Primary warnings (red flashing, audio, highest priority)
Secondary warnings (amber, needs addressing but not immediately)
Advisory warnings (green, device selected on)
Master caution/attention getters (press to cancel each warning)
Master control unit (MCU)

Question 24

What does the system test switch test?

Answer 24

Operation of a test switch tests the warning system, captions, and lamps (but not the systems from which the warnings are derived)