Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Engines > Chapter 3 > Flashcards

Chapter 3 Flashcards

1
Q

The function of a fuel system and what it’s necessary for

A

Combustion
Starting
Acceleration
Stable running under all conditions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are fuel requirements

A

Ease of flow in all operating conditions
Quick and easy starting of the engine
Complete combustions under all conditions
High calorific value
Non corrosive
No harmful products to flame tube/ turbines
Minimum fire hazard
Provide lubrication

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Name fuel system corrosive properties

A

Water content
Sulphur compounds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Additives given to fuel

A

Reduce contamination levels and micro-biological growth
Minimise corrosion
Enhance lubrication

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is FSII , what does it do

A

Inhabits the fuel system against icing
Inhibits against fungal system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Name fuel types

A

AVTUR
AVGAS

( always refer to the AMM for correct fuel )

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the three main sources of fire hazard

A

Fuel spillage , ignition of vapour by sparks
Fuel spillage on a hot surface
Existence of flammable or explosive mixture

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Fuel pump types

A

Piston type pump
Spur gear

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What varies the output of the spur type pump

A

The angle of the swashplace

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Explain key points of a Half-ball valve or spill valve

A

Changes the awash plate angle and piston stroke
Increases decreases engine RPM
Varies servo output and so servo pressure
Up and down movement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Explain key points of a Spur gear type pump

A

Lighter simpler less expensive
Flow is between gear tech and outer casting
Pressure is built by restriction down stream of the pump
PRV is fitted to maintain system pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is centrifugal governor , what does it consist of

A

Used to manage fuel supply

Engine driven shaft
Flyweights
Datum spring
Throttle valve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Governor operation

A

At rest - no drive , weights held under spring pressure, fuel valve fully open

Running up - drive increases , weight moves out of centrifugal force , valve started to close , fuel flow starts to restrict

Governed speed - speed increases the weights moves further out against the spring until centrifugal force is balanced by spring tension

Load changes - load on drive increases , speed decrease and weights will move in under the force of the spring , fuel valve open wider and admit more fuel , engine accelerates back to the governed speed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Name fuel system components

A

LP filter
Fine filter
HP pump
Fcu &throttle
PRV
FCU 60 psi
Solenoid valve & NRV
Torch igniter
HP cock
Rotary atomiser
Free turbine governor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is an LP Filter and Fine Filter

A

LP- provides protection for metered fuel
Fine - protects pump from debris

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is an HP Pump

A

Increases fuel pressure against debris

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is an FCU 60 psi

A

Feed fuel to torch igniter during the start cycle , whilst fuel pressure is below 60 psi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is a solenoid valve & NRV

A

Allows fuel to the torch inviter during the start cycle , then P2 air purges the Torch igniter after the start is terminated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What does Fadec stand for

A

Full Authority Digital Engine Control

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What does a FADEC system do

A

The opportunity to greatly reduce the complexity of hydro-mechanical and pneumatic engine systems

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Benefits of FADEC systems

A
  • reduced weight

-automation brings reduced pilot workload

  • optimised control giving more efficiency
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What does FADEC systems typically consist of

A

ECU
Hydro mechanical unit
Various sensors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

How is FADEC made more reliable

A

Having two channels

Channels A&B

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What to do for Fuel System Maintenance , and what should be done before

A

Safety and maintenance notes and SDS must be read

Scrupulous cleanliness

Fit blanks to all open pipes and unions to avoid ingress of contamination

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What has to be checked/ fixed on Fuel systems
Throttle adjustment Filters Rigid pipelines Flexible pipelines Leak checks Fuel flow tests
26
What to check when working on throttle adjustment
Rigged so no restriction to fuel , make sure datum’s are correct
27
What to check when replacing filters
Replace IAW relevant Aircraft Maintenance manual Examine for damage
28
What to check when replacing filters
Replace IAW relevant Aircraft Maintenance manual Examine for damage
29
What to check on pipelines flexible and rigid
Rigid : Prevent fracture and vibrations Secure Flexible : Sure not twisted Examined for cleanliness and damage Seals should be lubricated if necessary Union nuts must be correctly locked
30
What to check on pipelines flexible and rigid
Rigid : Prevent fracture and vibrations Secure Flexible : Sure not twisted Examined for cleanliness and damage Seals should be lubricated if necessary Union nuts must be correctly locked
31
When must be checked with leak checks
Fuel pipe or filter disturbed Must be run at normal pressure
32
When are fuel flow tests not carried out
On Engines When called for in the maintenance Manual or whenever the system has been disturbed the check as at the airframe fuel system connection to the engine
33
What is the internal air system definition
As the airflow that does not directly contribute to the engine thrust
34
Function of the air system
To preform safe and efficient operation of the engine
35
Functions of Internal air systems
Sealing bearings, chambers and labyrinth seals Ventilation for torch igniters Anti icing Air pressure to the ECU Pressure balance of HP and power turbines Internal cooling
36
External functions of air systems
Cabin air con Sand filter Winch motor operation Cooling accessories
37
Internal cooling what parts use the air
Main shaft and main bearings ( cooled by compressor air ) Seals ( prevents oil loss) Pressure balancing ( reduce loading ) Combustion chamber components( protects wall from flame and cools outer wall ) Turbine assembly ( reduce temperature)
38
Cockpits indications when anti icing is switched on
A slight rise in JPT ( jet pipe temp) Slight drop in engine rpm
39
What system do turbo prop and turbo shaft engines tend to use
Electrical ice protection systems
40
Names systems that monitor basic GTE ( gas turbine engine)
Engine temp Oli pressure and oil temp Engine RPM Torque EPR Fuel Flow Vibration
41
Jet pipe temperature uses which systems and is it independent from the other Systems
Independent system Signals from thermocouples or pyrometers
42
Describe a thermocouples
Inside probes Two wires of dissimilar metals joined by metal guard tube As heat is applied a small electrical current is generated Signal transmitted to junction box and amplified and displayed in the cockpit as degrees C
43
44
Describe Pyrometers
Optical device that views the turbine blades Connected to a infra red detector via fibre optic cable Enables rapid , accurate measurements of temp Requires bleed air to keep lens clean
45
Pyrometers uses what to measure Thermocouples use what to measure
Pyrometers - resistance Thermocouples - potential energy
46
How is engine engine RPM measured
Tachometer generator Mounted on accessory gear box Generates an electrical signal Indicates speed as a percentage figure of normal RPM
47
What is Engine Pressure Ratio
Indicated the thrust performance Typically measure the ratio turbine discharge pressure and compressor inlet pressure
48
What is fuel flow indication
Rate of fuel consumption Done by fuel flow transmitter
49
How is vibrations measure
By piezoelectric accelerometer Contains a material that produces an electric current when squeezed by the force produced by vibration
50
What is the modern Tech used for instruments indications
Liquid crystal Display tech
51
Fire system requirements
Detect immediately Suppressed asap Prevent spreading
52
What divided the engine bays to help prevent the spread of fire , what is it made from
Bulkheads Stainless steel Or titanium
53
Describe Detection of fire
Not give false information Uses fire wire
54
How does FireWire operate
The resistance of the filling material will decrease as the temperature increases , causing a circuit between the outer casing and central electrode
55
Describe structure of FireWire
Outer body ( stainless steal ) Filling material ( glass and aluminium oxide ) Central electrode
56
Installation of FireWire
Easily installed Continuous loop Venerable to damage due to vibration System still works with breaks
57
Cockpit indications for Fire
Flashing red lights Audible warnings Alarm bells
58
What can destroy FireWire , why
Moisture destroys the negative temperature co-efficient
59
How to test Fire Detection
Simulate an Overheat Condition This is a test facility and does not operate the system
60
Where is suppression located
Outside the fire risk zone
61
Describe operation of a 2shot system
1. Audible alert 2. Flashing attention getter 3. Fire caption warning panel 4. Light in the fire extinguisher operation handle/ switch 5. A light in the relevant fuel shut off or H.P cock
62
Operation by the pilot of fire resistance
1. Close engine control lever 2. Press appropriate extinguisher button 3. Low pressure warning light illuminates 4. If Fire light doesn’t turn of after 15s operate cross feed system 5. Repress button 1
63
What must you ensure before working on Fire detection system & suppression
Electrical power is switched off and disconnect the cartridge leads
64
Maintenance of Fire resistance and suppression
Checking pressure of extinguishing Weighing fire bottles
65
Extinguisher removal
1. Ensure electrically isolated 2. Ensure electrically disconnected 3. Avs remove explosive cartridge 4. Extinguisher and cartridges to be stored separately 5. Cartridges to be stored in ammo compound
66
Name Engine controls
HP Cock Throttle Centrifugal Governor
67
Name three types of control cables
Bowden Teleflex Bowdenflex
68
What is a Bowden control
Lightly loaded components Operates in pull mode only Needs a spring for return
69
What is a teleflex control
Inner cable with wire helix wrapped around it Covered by and outer conduit Two way in operation System is lubricated
70
What is a Bowdenflex
Flat rod running on bearings Two way operation Can withstand heat Not lubricated
71
Maintenance factors on GTE mechanical controls
Control runs - restriction free Control runs- correctly rigged Rigged- carried out IAW aircraft pubs Stops - wear on control stops , caused by milling Freedom of movement - freely easily move Leak checks
72
73
What are independent checks
Following any maintenance activity on control systems Done by authorised person Nothing to do with task
74

Engines (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions