Maintenance Practices M7.14 Sheet Metal

Question 1

How do you know which direction the grain is running on sheet metal

Answer 1

Same direction as the writing is stamped

Question 2

When bending metal what must be remembered

Answer 2

Bend 90° to the grain

Question 3

What stresses is sheet metal subject to when being bent

Answer 3

Tensile and compression forces

Question 4

Where does the neutral axis run on a metal that is being bent

Answer 4

The centre

Question 5

How is sheet metal stored

Answer 5

In a frame with appropriate paperwork

Question 6

What is important to remember about the Neutral line

Answer 6

It is in neither compression or tension

Question 7

What is important to remember about K factor

Answer 7

For every 90° bend K factor = 1

Question 8

What is the mood point

Answer 8

Where the mold lines intersect

Question 9

What is subtracted from EACH flat

Answer 9

Set back

Question 10

What are bends inspected for after bending

Answer 10

Cracks

Question 11

What is the bend sight line

Answer 11

1 bend radius from the bend tangent line

Question 12

When bending ally what must you remember

Answer 12

Might have to go slightly over due to spring back

Question 13

What is max juggle

Answer 13

2-3 thickness maximum

Question 14

What is a room temp cure

Answer 14

18-25°c 48 hours to 7 days

Question 15

When increasing bonding temp to 50-70°c how quick can cure time be

Answer 15

2-4 hours

Question 16

What is hot bonding controlled with

Answer 16

Thermocouples

Question 17

Does it take a longer time or shorter time for a cure to carry out in warm temp

Answer 17

Shorter time when warmer

Question 18

What is a disadvantage of using a heat lamp

Answer 18

Can cause high surface temps

Question 19

What are autoclaves

Answer 19

Big ovens giving ideal bonding

Question 20

What is a disadvantage of heat blankets

Answer 20

Can’t be used on complicated shapes

Question 21

What is the two wipe method

Answer 21

A solvent wipe and then a dry wipe before bonding

Question 22

What is used for detecting sub surface flaws

Answer 22

Ultrasound

Question 23

How are chains identified

Answer 23

Pitch, width between plates and roller diameter

Question 24

How is a change in direction in chains achieved

Answer 24

A bi planer block

Question 25

What are chain standards governed by

Answer 25

BS228

Question 26

What should be done if a chain is disassembled

Answer 26

It should be proof loaded once reassembled

Question 27

When should a chain be replaced with relation to wear

Answer 27

If wear is over 2%

Question 28

When not being used how are chains stored

Answer 28

In grease proof paper

Question 29

How would you know if push pull tubes are in safety

Answer 29

Witness hole

Question 30

What is the purpose of backlash

Answer 30

Prevents gears from jamming and room for lubrication

Question 31

What are the 2 different clearance fits

Answer 31

Running and free running

Question 32

What is the standard of ISO system limits and fits

Answer 32

BS4500

Question 33

If a repair is done to a control surface what must be done afterwards

Answer 33

It will need rebalancing

Question 34

What is the definition of sealant

Answer 34

Confines liquids and gasses in given areas to prevent them from entering other areas

Question 35

What are injection seals for

Answer 35

Holes

Question 36

What is a seal plane

Answer 36

A structural boundary where fuel cannot pass

Question 37

How are fuel tanks sealed

Answer 37

3 phase system

Question 38

When scraping sealant and choosing a scraper what must be remembered

Answer 38

Scraper should not be any harder than 2024 T3

Question 39

What altitude do lightning strikes normally occur

Answer 39

Between 5-15k feet during take off and decent

Question 40

How much can a single bolt of lightning be

Answer 40

1 million volts

Question 41

What are 2 types of lightning strike damage

Answer 41

Direct and indirect

Question 42

What is HIRF

Answer 42

High Frequency Radiated Field

Question 43

What type of aircraft are more likely to get hot with lightning strikes

Answer 43

Short haul

Question 44

If an overweight landing occurs what must be done

Answer 44

An overweight landing

Question 45

How is severe turbulence identified

Answer 45

Turbulence which causes large abrupt changes in altitude and attitude

Question 46

What’s the alternative way of cutting a cable

Answer 46

Anvil, hammer and chisel

Question 47

What must not be used to cut a cable

Answer 47

Oxy acetalyne torch

Question 48

No more than what for a suage tool

Answer 48

4 role sequences

Question 49

How to make sure a cable tension tester is operating correctly

Answer 49

Hold for 5 secs and no slips

Question 50

Which side of the turnbuckle had a left hand thread

Answer 50

The one with a groove

Question 51

How do you make sure a turnbuckle is in safety

Answer 51

Witness mark or hole