Cleaning and corrosion control

Question 1

Is there any requirement for cleaning an aircraft prior to an annual or 100 inspection?

Answer 1

Yes, in accordance with FAR part 43 appendix D

Question 2

Discuss the general precautions that should be observed when washing an airplane

Answer 2

Avoid or protect areas which may be damaged or contaminated, such as pitot tubes and static tubes hinges, sealed areas and bearings

Question 3

What are some of the more common light duty cleaning agents?

Answer 3

Soap or detergent and water

Question 4

What materials are commonly used as heavy duty cleaners

Answer 4

Solvents, and emulsions

Question 5

What are the preferred cleaners for plastic surfaces such as windshields?

Answer 5

Mild soap in water or manufacture, approved, cleaners

Question 6

What type of cleaning agents should be used to remove grease oil or fuel from aircraft tires?

Answer 6

Soap and water

Question 7

Give examples of the factors that cause or influence corrosion

Answer 7

Environmental conditions, dissimilar metals, type of metal

Question 8

Name the different types of corrosion that can be found on an aircraft

Answer 8

Fretting, exfoliation, filiform, pitting surface intergranular

Question 9

What is the cause of filiform corrosion

Answer 9

Improper or incomplete, caring of a wash primer prior to painting

Question 10

What is a visible signs of filiform corrosion?

Answer 10

Blistered paint surfaces

Question 11

What are the two primary factors that may cause development of stress corrosion

Answer 11

It corrosive environment and sustained tensile stress

Question 12

What are the areas of an aircraft that are prone to corrosion?

Answer 12

Battery compartments, bag bin, galleys, landing gear, wing flap, lavatories, end, any areas that can and trap water

Question 13

What is another name for corrosion caused by contacted dissimilar metals

Answer 13

Galvanic corrosion

Question 14

The lifting and flaking of a metal surface due to the buildup of corrosion products as a result of severe intergranular corrosion is an indication of what form of corrosion

Answer 14

Exfoliation

Question 15

What are the visible signs of fretting corrosion?

Answer 15

The corrosion residue has a dark, smoky appearance streaming back from rivet heads

Question 16

What type of corrosion causes a smoking rivet?

Answer 16

Fretting corrosion

Question 17

What is the most common type of corrosion?

Answer 17

Surface corrosion

Question 18

What form or corrosion is an attack along the grain boundaries of an alloy that is usually caused by improper heat treatment

Answer 18

Intergranular corrosion

Question 19

What type of corrosion can be found in battery compartment?

Answer 19

Direct, chemical, attack or chemical corrosion

Question 20

Where is stress corrosion most likely to occur on an aircraft

Answer 20

In any metal component that is continually under a tensile stress, the metal around holes in casting that are fitted with pressed and bushings are suspectible to stress corrosion

Question 21

Where is intergranular corrosion most likely to occur on an aircraft

Answer 21

A long grain boundaries of aluminum alloys that have been improperly he treated. Extruded aluminum alloy suspectible to intergranular corrosion.

Question 22

Why are piano type hinges prime spots for corrosion?

Answer 22

The steel pin an aluminum hinge material are dissimilar metals in the hinge design tends to trap, moisture and contaminants

Question 23

What is the best way to protect piano hinges from

Answer 23

Keep them clean and properly lubricated

Question 24

What are corrosion preventative measures for aircraft?

Answer 24

Cleaning, lubrication treatment, sealing, inspection

Question 25

Describe the tools that should be used to remove corrosion from anodized aluminum surfaces

Answer 25

Nylon scrub pads such a scotch Brite bristle brushes, aluminum wool aluminum wire brush

Question 26

Describe the tools that should be used to remove corrosion from titanium

Answer 26

Stainless steel wool or brushes, scotch, bright, abrasive blast with glass beads

Question 27

What is the purpose of Alodine

Answer 27

Alodine is a chemical process that deposits, a protective film on aluminum alloys the film improves, corrosion resistance, and paint adhesion

Question 28

For what reason should you avoid cleaning anodized aluminum services with aluminum metal polish?

Answer 28

Aluminum metal polish should not be used on anodize aluminum surfaces because it will remove the anodized coating

Question 29

Why should aircraft fabrics in plastics be cleaned only with recommended cleaners

Answer 29

Recommended cleaners cause the least amount of deterioration or damage

Question 30

Describe the effects of using steel brushes or steel wool to remove corrosion from aluminum surfaces

Answer 30

Steel brushes or steel wool must not be cleaned Aluminum because the steel particles can be embedded in the aluminum and cause corrosion

Question 31

How was the inside of a structural steel tubing protected from corrosion?

Answer 31

The tubing is filled with hot linseed oil and then drained

Question 32

What are the two types of surface treatments used on aluminum surfaces

Answer 32

Anodizing in anodizing

Question 33

What can be used to repair the anodize surface on an aluminum alloy part?

Answer 33

Chemical conversion coding, such as Alodine

Question 34

What solvent is recommended for removing grease from aircraft fabric prior to doping it

Answer 34

(MEK) methyl ethyl ketone or lacquer thinner

Question 35

What is used to neutralize the electrolyte from a lead acid battery that has been spilled on an aircraft structure

Answer 35

Is solution of boric acid and water or vinegar