AMT: Airframe Oral & Practical Exam Guide-Questions with Correct
Answers/Verified
What is a rejuvenator? - ✔✔A slow-drying finishing material that has potent solvents and
plasticizers that soften a dried surface film and restore resilience to the film.
Does rejuvenator restore strength to the fabric? - ✔✔No, it only restores resilience to the
finish.
Why is the first coat of dope brushed onto the fabric? - ✔✔To ensure thorough penetration
and encapsulation of all the fibers.
What is the general reason for runs and sags in a finish that is being sprayed onto a flat
surface? - ✔✔Too much dope is being applied. The film is too thick.
What is the most common cause for dope roping? - ✔✔The dope was improperly thinned or
it was too cold.
What causes pinholes in a dope finish? - ✔✔Excessive atomizing air pressure on the spray
gun.
Why should the first coat of dope be thinned? - ✔✔To ensure thorough penetration and
encapsulation of all of the fibers.
Why is aluminum pigmented dope used on a fabric-covered aircraft? - ✔✔To protect the
clear dope and the fabric from the harmful effects of the sun.
What safety precaution must be observed when sweeping a paint room that has dried dope
or lacquer overspray on the floor? - ✔✔The floor must be wet down with water before it is
swept. Static electricity from dry sweeping can cause a fire.
,Why should a fabric-covered surface be electrically grounded when dry-sanding it? -
✔✔Dry-sanding can create enough static electricity on the surface that it can cause a spark
and ignite the dope fumes inside the structure.
What instructions must be followed when covering and finishing an aircraft with materials
specified in a Supplemental Type Certificate (STC)? - ✔✔The instructions that are a part of
the STC.
What finishing materials must be used when recovering an aircraft using an STC? - ✔✔The
finishing materials specified by the STC.
How thick should a coat of wash primer be that is used on an aluminum alloy structure? -
✔✔It should be thin enough that it does not hide the surface of the metal.
When mixing epoxy paint, should the converter be added to the resin or the resin to the
converter? - ✔✔The converter should always be added to the resin, never the resin to the
converter.
What are three types of primer that may be used when painting an aircraft? - ✔✔Zinc
chromate primer, wash primer, and epoxy primer.
What type of thinner is used with zinc chromate primer? - ✔✔Toluol or toluene.
What type of primer is used when the maximum protection of the metal is required? -
✔✔Epoxy primer.
What should be done to a corroded aluminum alloy surface after the corrosion has been
removed by mechanical methods? - ✔✔The surface should be treated with a chemical
conversion coating before the topcoats are applied.
What may be done to the surface to prevent filiform corrosion beneath the topcoat? -
✔✔Be sure that the primer is properly and completely cured.
,How is the finish removed from a fiberglass aircraft component that is being repaired? -
✔✔The finish must be sanded off. Paint remover can soften the resin of which the
component is made.
How can a vinyl film decal be removed from an aluminum alloy surface? - ✔✔Place a cloth
saturated with cyclohexanone or MEK over the decal until it is softened, and scrape it off of
the surface with a plastic scraper.
What is a cause of poor adhesion between the topcoat and the fill coats on a fabric surface?
- ✔✔Too much aluminum powder in the aluminum pigmented dope.
What is a cause of a rough finish on a freshly sprayed surface? - ✔✔Too high atomizing air
pressure on the spray gun.
What causes sags and runs on a surface that has just been sprayed? - ✔✔Too much finishing
material being applied in one coat.
What causes orange peel, or spray mottle, in a finish? - ✔✔Incorrect paint viscosity or
improper setting of the spray gun.
What causes pinholes in a finish? - ✔✔Excessive atomizing air on the spray gun.
What causes blushing in a dope finish? - ✔✔Too high humidity.
What causes fisheyes in the finish? - ✔✔Localized surface contamination.
For maximum strength of a formed sheet metal fitting, should the bend be made along or
across the grain of the metal? - ✔✔Across the grain.
What determines the minimum bend radius that can be used when forming a sheet metal
structural fitting? - ✔✔The alloy, the metal thickness, and its hardness.
, What is meant by the neutral axis in a sheet of metal? - ✔✔A plane within the metal that
neither stretches nor shrinks when the metal is being bent.
What is a mold line in the development of a flat pattern for a formed metal part? - ✔✔An
extension of the flat sides beyond the radius.
What is the bend tangent line? - ✔✔A line in a flat pattern layout at which the bend starts.
What is meant by setback? - ✔✔The distance the jaws of a brake must be set back from the
mold line to form a bend.
What is meant by bend allowance? - ✔✔The actual amount of metal in a bend. It is the
distance between the bend tangent lines in a flat pattern layout.
What is a sight line? - ✔✔A line drawn on a flat pattern layout within the bend allowance
that is one bend radius from the bend tangent line. When the sight line is directly below the
nose of the radius bar on the brake, the bend will start at the bend tangent line.
What type of device is a Cleco fastener? - ✔✔A patented fastener that is inserted in the rivit
holes and used to hold the two pieces of sheet metal together until they can be riveted.
What is the main function of throatless shears in an aircraft sheet metal shop? -
✔✔Throatless shears are used to cut mild carbon steel up to 10-gage, and stainless steel up
to 12-gage. They can be used to cut irregular curves in the metal.
What kind of metal forming is done by a slip roll former? - ✔✔Simple curves with a large
radius.
What kind of metal forming is done by bumping? - ✔✔Compound curves in sheet metal.
When forming a curved angle, what must be done to the flanges? - ✔✔The flanges must be
stretched for a convex curve and shrunk for a concave curve.
Answers/Verified
What is a rejuvenator? - ✔✔A slow-drying finishing material that has potent solvents and
plasticizers that soften a dried surface film and restore resilience to the film.
Does rejuvenator restore strength to the fabric? - ✔✔No, it only restores resilience to the
finish.
Why is the first coat of dope brushed onto the fabric? - ✔✔To ensure thorough penetration
and encapsulation of all the fibers.
What is the general reason for runs and sags in a finish that is being sprayed onto a flat
surface? - ✔✔Too much dope is being applied. The film is too thick.
What is the most common cause for dope roping? - ✔✔The dope was improperly thinned or
it was too cold.
What causes pinholes in a dope finish? - ✔✔Excessive atomizing air pressure on the spray
gun.
Why should the first coat of dope be thinned? - ✔✔To ensure thorough penetration and
encapsulation of all of the fibers.
Why is aluminum pigmented dope used on a fabric-covered aircraft? - ✔✔To protect the
clear dope and the fabric from the harmful effects of the sun.
What safety precaution must be observed when sweeping a paint room that has dried dope
or lacquer overspray on the floor? - ✔✔The floor must be wet down with water before it is
swept. Static electricity from dry sweeping can cause a fire.
,Why should a fabric-covered surface be electrically grounded when dry-sanding it? -
✔✔Dry-sanding can create enough static electricity on the surface that it can cause a spark
and ignite the dope fumes inside the structure.
What instructions must be followed when covering and finishing an aircraft with materials
specified in a Supplemental Type Certificate (STC)? - ✔✔The instructions that are a part of
the STC.
What finishing materials must be used when recovering an aircraft using an STC? - ✔✔The
finishing materials specified by the STC.
How thick should a coat of wash primer be that is used on an aluminum alloy structure? -
✔✔It should be thin enough that it does not hide the surface of the metal.
When mixing epoxy paint, should the converter be added to the resin or the resin to the
converter? - ✔✔The converter should always be added to the resin, never the resin to the
converter.
What are three types of primer that may be used when painting an aircraft? - ✔✔Zinc
chromate primer, wash primer, and epoxy primer.
What type of thinner is used with zinc chromate primer? - ✔✔Toluol or toluene.
What type of primer is used when the maximum protection of the metal is required? -
✔✔Epoxy primer.
What should be done to a corroded aluminum alloy surface after the corrosion has been
removed by mechanical methods? - ✔✔The surface should be treated with a chemical
conversion coating before the topcoats are applied.
What may be done to the surface to prevent filiform corrosion beneath the topcoat? -
✔✔Be sure that the primer is properly and completely cured.
,How is the finish removed from a fiberglass aircraft component that is being repaired? -
✔✔The finish must be sanded off. Paint remover can soften the resin of which the
component is made.
How can a vinyl film decal be removed from an aluminum alloy surface? - ✔✔Place a cloth
saturated with cyclohexanone or MEK over the decal until it is softened, and scrape it off of
the surface with a plastic scraper.
What is a cause of poor adhesion between the topcoat and the fill coats on a fabric surface?
- ✔✔Too much aluminum powder in the aluminum pigmented dope.
What is a cause of a rough finish on a freshly sprayed surface? - ✔✔Too high atomizing air
pressure on the spray gun.
What causes sags and runs on a surface that has just been sprayed? - ✔✔Too much finishing
material being applied in one coat.
What causes orange peel, or spray mottle, in a finish? - ✔✔Incorrect paint viscosity or
improper setting of the spray gun.
What causes pinholes in a finish? - ✔✔Excessive atomizing air on the spray gun.
What causes blushing in a dope finish? - ✔✔Too high humidity.
What causes fisheyes in the finish? - ✔✔Localized surface contamination.
For maximum strength of a formed sheet metal fitting, should the bend be made along or
across the grain of the metal? - ✔✔Across the grain.
What determines the minimum bend radius that can be used when forming a sheet metal
structural fitting? - ✔✔The alloy, the metal thickness, and its hardness.
, What is meant by the neutral axis in a sheet of metal? - ✔✔A plane within the metal that
neither stretches nor shrinks when the metal is being bent.
What is a mold line in the development of a flat pattern for a formed metal part? - ✔✔An
extension of the flat sides beyond the radius.
What is the bend tangent line? - ✔✔A line in a flat pattern layout at which the bend starts.
What is meant by setback? - ✔✔The distance the jaws of a brake must be set back from the
mold line to form a bend.
What is meant by bend allowance? - ✔✔The actual amount of metal in a bend. It is the
distance between the bend tangent lines in a flat pattern layout.
What is a sight line? - ✔✔A line drawn on a flat pattern layout within the bend allowance
that is one bend radius from the bend tangent line. When the sight line is directly below the
nose of the radius bar on the brake, the bend will start at the bend tangent line.
What type of device is a Cleco fastener? - ✔✔A patented fastener that is inserted in the rivit
holes and used to hold the two pieces of sheet metal together until they can be riveted.
What is the main function of throatless shears in an aircraft sheet metal shop? -
✔✔Throatless shears are used to cut mild carbon steel up to 10-gage, and stainless steel up
to 12-gage. They can be used to cut irregular curves in the metal.
What kind of metal forming is done by a slip roll former? - ✔✔Simple curves with a large
radius.
What kind of metal forming is done by bumping? - ✔✔Compound curves in sheet metal.
When forming a curved angle, what must be done to the flanges? - ✔✔The flanges must be
stretched for a convex curve and shrunk for a concave curve.
