MEA109 Part C

Question 1

True or false - Pure iron is unsuitable for use on aircraft.

Answer 1

True

Question 2

Why is carbon added to pure iron

Answer 2

to increase it strength

Question 3

What are the 2 components of alloy steel?

Answer 3

Carbon steel and other metal

Question 4

Low carbon steel

Answer 4

0.1% - 0.3% carbon content

Safety wire

Question 5

Medium carbon steel

Answer 5

0.3% - 0.5% carbon content

Rod ends, light forgings

Question 6

High carbon steel

Answer 6

0.50% - 1.05% carbon content

Flat springs, coil springs

Question 7

What type of steel is used extensively in the manufacture of aircraft bolts & nuts?

Answer 7

nickel steel

Question 8

Anti-friction ball & roller bearings are made from _______ steel due to its improved hardness & excellent wear resistant properties.

Answer 8

chromium steel

Question 9

List 2 mechanical properties of chrome nickel steel that makes it suitable for use in manufacture of control cables

Answer 9

high strength

corrosion resistant

Question 10

What are the 2 other names for chrome nickel steel

Answer 10

stainless steel

CRES - corrosionn resistant stee;

Question 11

True or false – Fasteners suited for high temperature applications are usually made from inconel.

Answer 11

True

Question 12

What type of steel is used in the manufacture of spanners?

Answer 12

chrome vanadium

Question 13

Give 2 examples of aircraft components made from chrome molybdenum steel alloy.

Answer 13

landing gear structure

engine mounts

Question 14

What type of metal is widely used in the construction of aircraft structures?

Answer 14

aluminium alloy

Question 15

What is meant by the term “aluminium alloy”

Answer 15

pure aluminium mixed with another metal

Question 16

1XXX
2XXX
5XXX
7XXX

Answer 16

Pure aluminium
copper
magnesium
zinc

Question 17

What is the reason that 1XXX series aluminium is not used in the construction of aircraft structures?

Answer 17

Its not strong enough

Question 18

True of false – 1XXX series has excellent corrosion resistance

Answer 18

True

Question 19

For aircraft structures, what are the most commonly used aluminium alloys in the 2XXX series?

Answer 19

2017 and 2024 aluminium alloy

Question 20

ALCLAD is a type of sheet metal that has ______ (material) rolled over an aluminium alloy core to approximately __% thickness on ___ (both or each) side(s).

Answer 20

ALCLAD is a type of sheet metal that has pure aluminium rolled over an aluminium alloy core to approximately 5% thickness on each side(s).

Question 21

Malleability

Answer 21

able to be pressed, pounded or rolled into various shapes without being damaged

Question 22

Ductility

Answer 22

ability to be drawn, bent or twisted into various shapes without being damaged

Question 23

Hardness

Answer 23

ability to resist abrasion, penetration, cutting action or permanent distortion

Question 24

Brittleness

Answer 24

tendency to break or crack without change in shape

Question 25

Toughness

Answer 25

able to resist shearing or tearing

Question 26

Shear

Answer 26

the force of an slicing or cutting an object

Question 27

compression

Answer 27

the force of crushing an object

Question 28

torsion

Answer 28

the stress of an object when it is being twisted

Question 29

Tension

Answer 29

pulling an object apart

Question 30

What can be achieved by heat treating metals?

Answer 30

To change the mechanical properties so the metal will be more useful

Question 31

Heat treatment - Hardening

Answer 31

Hardness increases more brittle Rapid cooling in quenching medium such as oil, water,

Question 32

Heat treatment -Annealing

Answer 32

Produces soft, ductile metal Relieves internal stresses Very slow cool down in furnace

Question 33

Heat treatment -Tempering

Answer 33

Relieves internal stresses Reduces Brittleness Cooldown in still air (outside furnace)

Question 34

Heat treatment -Normalisng

Answer 34

Removes internal stresses set up by hear treating, casting, forming, machining

Question 35

True or false: The letter “T” designation is used to indicate the hardness condition of heat treated aluminium alloys.

Answer 35

True

Question 36

True of false – Natural ageing process occurs after the soaking step during heat treatment of aluminium alloys.

Answer 36

False

Question 37

What is meant by the term “natural ageing”?

Answer 37

developing maximum strength

Question 38

Certain aluminium alloys are solution heat treated then followed by a natural ageing process. These alloys are allowed to naturally age (harden) at room temperature over a period of ____ to develop their full properties after heat treatment

Answer 38

4 days

Question 39

What heat treatment process would be necessary to avoid cracking of an alloy due to prolonged cold working?

Answer 39

annealing

Question 40

Brinell Hardness Tester

Answer 40

Forces a hardened spherical ball to indent the metal surface After test is done, diameter of impression is measured with a calibrated microscope

Question 41

Rockwell hardness tester

Answer 41

Forces a conical penetrator to indent the material at a specified load Test hardness numbers are based on difference between depth of penetration at major and minor loads

Question 42

List 2 problems with the use of cellulose acetate plastics.

Answer 42

Tendency to shrink | Slight yellow tint

Question 43

List 2 benefits of acrylic plastics over cellulose acetate plastics.

Answer 43

Practically colourless stiffer than cellulose acetate

Question 44

What is the effect of further addition of heat on thermosetting plastics once they have been fully cured?

Answer 44

Further addition of heat on thermosetting plastics can cause deformation or structural weakening

Question 45

What is the definition for a composite material

Answer 45

A material that consists of two or more different meterials

Question 46

What are the 2 components that make a strong composite part?

Answer 46

fibre, surrounded and held in place by a resin

Question 47

What is the trade name for aramid?

Answer 47

kevlar

Question 48

A laminated structure with a core centre is called a _____ structure

Answer 48

A sandwich structure is a laminated structure with a core centre

Question 49

What document lists the PPE required to worn when working with composite materials & resins?

Answer 49

SDS

Question 50

Hydraulic system pressure: 1500 psi to 3000psi

Answer 50

CRES - Corrosion resistant steel

Question 51

Hydraulic system pressure: Pressure up to 1500psi

Answer 51

Aluminium alloy

Question 52

Hydraulic system pressure: Pressure above 3000psi

Answer 52

Titanium

Question 53

True or false - The sizes for rigid tubing are measured from the inside diameter of the tubing

Answer 53

False: Measured from outside

Question 54

Marking decals - Rigid tubing: Blue & yellow background

Answer 54

Hydraulic

Question 55

Marking decals - Rigid tubing: Grey background

Answer 55

De-icing

Question 56

Marking decals - Rigid tubing: Red background

Answer 56

Fuel

Question 57

Marking decals - Rigid tubing: Green background

Answer 57

Breathing Oxygen

Question 58

What type of rigid tube fitting is used on fluid systems with: High system pressure

Answer 58

Flareless fitting

Question 59

What type of rigid tube fitting is used on fluid systems with: Very low pressure

Answer 59

Beaded type fitting

Question 60

Flexible hoses are most suitable for what type of applications?

Answer 60

To connect moving parts with stationary parts in locations which are prone to vibration or require a great amount of flexibility.

Question 61

Name the 3 items that make up a flexible hose line.

Answer 61

Butyl, Buna - N, Neoprene

Question 62

What is the purpose of a continuous stripe on the outer cover on some flexible hoses?

Answer 62

The lay line shows that the hose has been installed without twisting. The line has to be straight.

Question 63

True or false - The sizes for flexible hoses are measured from the outside diameter of the tubing.

Answer 63

False: Measured from inside

Question 64

True or False -The swaged end fittings on flexible hoses can be reused

Answer 64

False: cannot be reused

Question 65

What is the colour coding for standard hose fitting made of steel & aluminium alloy?

Answer 65

AN Steel fitting: Black | AN Aluminium fitting: Blue

Question 66

What is the purpose of fluid line blanks?

Answer 66

to prevent the ingress of any contaminants