CLEANING AND CORROSION CONTROL
ORAL. EXAM QUESTIONS AND
ANSWERS | 2026 UPDATE | 100%
CORRECT.
Is there a requirement for cleaning an aircraft prior to an annual or 100-hour inspection? -
ANS Yes, in accordance with FAR Part 43, Appendix D.
What precautions should be observed when washing an airplane? - ANS Avoid or protect
areas that may be damaged or contaminated such as pitot tubes, static ports, hinges, sealed
areas, and bearings.
What are some common light duty cleaning agents? - ANS Soap or detergents and water.
Which materials are commonly used as heavy duty cleaners? - ANS Solvents and emulsions.
What are the preferred cleaners for plastic surfaces such as windshields? - ANS Mild soap and
water or manufacturer-approved cleaners.
What type of cleaning agents should be used to remove grease, oil, or fuel from aircraft tires? -
ANS Soap and water.
What factors cause or influence corrosion? - ANS Environmental conditions, dissimilar
metals, type of metal, presence of electrolytes or contaminants, and condition of protective
coatings.
@COPYRIGHT ALL RIGHTS RESERVED PAGE 1 OF 7
, What are the different types of corrosion that can be found on an aircraft? - ANS Surface,
intergranular, filiform, dissimilar metal, galvanic, oxidation, fitting, stress, fretting, and
exfoliation.
What causes filiform corrosion? - ANS Improper or incomplete curing of a wash primer prior
to painting and failure to completely wash off acidic surface contamination.
What are the visible signs of filiform corrosion? - ANS Blistered paint surfaces or
worm/thread-like tracks or patterns under the paint.
What are the two primary factors that may cause development of stress corrosion? - ANS A
corrosive environment and sustained tensile stress.
Where can a person find warnings and information on toxicity or flammability of chemicals used
in surface treatment? - ANS The Safety Data Sheet (SDS).
What is the height of registration marks to be displayed on rotorcraft manufactured after 1984?
- ANS They must be at least 12 inches high.
When is it acceptable for a U.S. registered aircraft to be operated without the registration and
nationality marks? - ANS When operated for exhibition, such as in a motion picture,
television production, or an air show.
What areas of an aircraft are prone to corrosion? - ANS Exhaust trail areas, engine
compartments, vent openings, battery compartments, bilge areas, lavatories, wheel wells,
landing gear, wing flap recesses, under galleys, piano hinges, and any areas that entrap water.
What is another name for corrosion caused by contact of dissimilar metals? - ANS Galvanic
corrosion.
@COPYRIGHT ALL RIGHTS RESERVED PAGE 2 OF 7
ORAL. EXAM QUESTIONS AND
ANSWERS | 2026 UPDATE | 100%
CORRECT.
Is there a requirement for cleaning an aircraft prior to an annual or 100-hour inspection? -
ANS Yes, in accordance with FAR Part 43, Appendix D.
What precautions should be observed when washing an airplane? - ANS Avoid or protect
areas that may be damaged or contaminated such as pitot tubes, static ports, hinges, sealed
areas, and bearings.
What are some common light duty cleaning agents? - ANS Soap or detergents and water.
Which materials are commonly used as heavy duty cleaners? - ANS Solvents and emulsions.
What are the preferred cleaners for plastic surfaces such as windshields? - ANS Mild soap and
water or manufacturer-approved cleaners.
What type of cleaning agents should be used to remove grease, oil, or fuel from aircraft tires? -
ANS Soap and water.
What factors cause or influence corrosion? - ANS Environmental conditions, dissimilar
metals, type of metal, presence of electrolytes or contaminants, and condition of protective
coatings.
@COPYRIGHT ALL RIGHTS RESERVED PAGE 1 OF 7
, What are the different types of corrosion that can be found on an aircraft? - ANS Surface,
intergranular, filiform, dissimilar metal, galvanic, oxidation, fitting, stress, fretting, and
exfoliation.
What causes filiform corrosion? - ANS Improper or incomplete curing of a wash primer prior
to painting and failure to completely wash off acidic surface contamination.
What are the visible signs of filiform corrosion? - ANS Blistered paint surfaces or
worm/thread-like tracks or patterns under the paint.
What are the two primary factors that may cause development of stress corrosion? - ANS A
corrosive environment and sustained tensile stress.
Where can a person find warnings and information on toxicity or flammability of chemicals used
in surface treatment? - ANS The Safety Data Sheet (SDS).
What is the height of registration marks to be displayed on rotorcraft manufactured after 1984?
- ANS They must be at least 12 inches high.
When is it acceptable for a U.S. registered aircraft to be operated without the registration and
nationality marks? - ANS When operated for exhibition, such as in a motion picture,
television production, or an air show.
What areas of an aircraft are prone to corrosion? - ANS Exhaust trail areas, engine
compartments, vent openings, battery compartments, bilge areas, lavatories, wheel wells,
landing gear, wing flap recesses, under galleys, piano hinges, and any areas that entrap water.
What is another name for corrosion caused by contact of dissimilar metals? - ANS Galvanic
corrosion.
@COPYRIGHT ALL RIGHTS RESERVED PAGE 2 OF 7
