A&P Aviation Mechanic General Oral Questions and
Answers 2022/2023 with complete solution
What are two reasons weight and balance control are important in an aircraft?
Safety of flight and most efficient operation of an aircraft.
Where is the center of gravity for most airplanes located in relation to the center
of lift?
The CG is normally ahead of the center of lift.
What is meant by the datum that is used for weight and balance computations?
It is a readily identified reference chosen by the aircraft manufacturer from which all
longitudinal locations on the aircraft are referenced.
What is meant by moment in the computation of weight and balance?
A force that tends to cause rotation. It is the product of the weight of an object in pounds
and the distance of the object from the datum in inches.
What is meant by the arm of an item installed in an aircraft?
The distance, in inches, between the center of gravity of the item and the datum.
Where do you find the arm of an item installed on an aircraft?
The Type Certificate Data Sheets for the aircraft.
What is meant by a moment index?
A moment divided by a constant such as 10, 100, or 1,000.
What is meant by the center of gravity range?
The distance in inches between the forward allowable center of gravity and the rearward
allowable center of gravity.
What is the significance of the empty weight center of gravity range of an
aircraft?
If the empty weight center of gravity falls within the EWCG range, the aircraft cannot be
legally loaded in such a way that it's loaded center of gravity will fall outside of the
allowable loaded CG range. Not all aircraft have an EWCG range.
Why is the empty weight center of gravity range not given in the Type Certificate
Data Sheets for some aircraft?
The empty weight center of gravity range is given only for aircraft that cannot be legally
loaded in such a way that the loaded center of gravity will fall outside of the allowable
limits.
What is meant by the mean aerodynamic chord(MAC)?
The chord of an imaginary airfoil that has the same aerodynamic characteristics of an
actual airfoil.
What is a loading envelope?
The enclosed area on a graph of an airplane's loaded weight and CG location. If lines
drawn from the weight and CG cross within this envelope the airplane is properly
loaded.
What is meant by permanent ballast for an aircraft?
Weight that is permanently installed in an aircraft to bring the empty weight center of
gravity into allowable limits.
Where must a record be kept of the current empty weight and the current center
of gravity of an aircraft?
,In the aircraft flight manual or weight and balance records required by 14 CFR §
23.1583.
Of what material are most low-pressure rigid fluid lines made?
1100-1/2 hard or 3003-1/2 hard aluminum alloy tubing.
Is the size of a rigid fluid line determined by its inside or its outside diameter?
Outside diameter.
When routing a fluid line parallel to an electrical wire bundle, which should be on
top?
Electrical wire bundle.
How can you distinguish an AN fluid line fitting from an AC fitting?
AN fitting has a shoulder between the end of the flare cone and the first thread. AC
fitting the threads extend all the way to the flare cone.
How tight should an MS flareless fitting be tightened?
Tighten the fitting by hand until it is snug, and then turn it with the wrench for 1/6-turn to
1/3-turn. Never turn it more the 1/3-turn.
What damage can be caused by overtightening an MS flareless fitting?
Overtightening drives the cutting edge of the sleeve deep into the tube and weakens it.
What kind of rigid tubing can be flared with a double flare?
5052-O and 6061-T aluminum alloy tubing in sizes from 1/8-inch to 3/8-inch OD.
Of what material should rigid fluid lines be made that carry high-pressure(3,000
psi or greater) hydraulic fluid?
Annealed or 1/4-hard corrosion-resistant steel.
What is the difference between the flare angle for aircraft and automotive fittings?
Aircraft fittings have 37º flare angle and automotive fittings use 45º.
What should be done to the end of a tube that is to be flared?
The cut end should be polished to remove any sharp edges that could cause the tubing
to crack.
What is the function of the lay line(the identification stripe) that runs the length of
a flexible hose?
To show if the line was twisted during installation.
Where are quick-disconnect fluid line couplings normally used in an aircraft
hydraulic system?
In the lines that connect the engine-driven pump into the hydraulic system.
Is the size of a flexible hose determined by its inside or its outside diameter?
Inside Diameter.
What is the minimum amount of slack that must be left when a flexible horse is
installed in an aircraft hydraulic system?
The hose should be at least 5% longer than the distance between fittings.
What is the principal advantage of Teflon hose for use in an aircraft hydraulic
system?
Teflon hose retains its high strength under conditions of high temperature.
How much pressure is used to proof-test a flexible hose assembly?
Varies but generally about two times operating pressure.
What is the proper type of nondestructive inspection to use for locating surface
cracks in an aluminum alloy casting or forging?
Zyglo or dye penetrant.
, What inspection method would be most appropriate for checking a nonferrous
metal part for intergranular corrosion?
Eddy Current inspection.
What inspection method would be most appropriate for checking the internal
structure of an airplane wing for corrosion?
X-Ray Inspection.
How does filiform corrosion usually appear on an aircraft structure?
As thread-like lines of puffiness under a film of polyurethane or other dense finish
system topcoats.
What inspection method would be most appropriate for checking a steel landing
gear component for stress cracks?
Magnetic Particle inspection.
What type of inspection is best suited for detecting a fault within a piece of
nonferrous metal?
Ultrasonic inspection.
Explain the procedure to use when making a dye penetrant inspection of a part.
Clean the part, apply the penetrant, and allow it to soak for recommended dwell time.
Remove the penetrant from the surface and apply the developer.
Why is it important that all parts be thoroughly cleaned before they are inspected
by the dye penetrant method?
Any grease or dirt in a fault will keep the penetrant from seeping into the fault.
Explain the procedure to use when performing a magnetic particle inspection of a
part.
Clean the part, magnetize it as directed by the service manual,flow the indicating
medium over the surface, and inspect under a blacklight. When the inspection is
complete, thoroughly demagnetize the part.
Why is it necessary to magnetize a part both circularly and longitudinally when
inspecting a steel part by the magnetic particle method?
To detect faults that extend across as well as lengthwise within the part.
Does circular magnetization detect parts that are across or lengthwise to the
part?
Lengthwise.
Why is it important that all engine parts which have been inspected by magnetic
particle method be completely demagnetized?
They will attract steel particles that are produced by engine wear and will cause damage
to bearing surfaces.
What is the principle of eddy current inspection?
A current is induced into the metal being tested by a test probe. The amount of induced
current is determined by the conductivity, mass, and permeability of the material, and
the presence of and faults or voids.
Why is it important that a piece of aluminum alloy be quenched immediately after
it is removed from the heat-treating oven?
To prevent intergranular corrosion.
What is meant by normalizing a piece of steel it has been welded or machined?
Normalizing will remove stresses locked into the material.
Explain the way a steel structure is normalized after it has been welded.
Answers 2022/2023 with complete solution
What are two reasons weight and balance control are important in an aircraft?
Safety of flight and most efficient operation of an aircraft.
Where is the center of gravity for most airplanes located in relation to the center
of lift?
The CG is normally ahead of the center of lift.
What is meant by the datum that is used for weight and balance computations?
It is a readily identified reference chosen by the aircraft manufacturer from which all
longitudinal locations on the aircraft are referenced.
What is meant by moment in the computation of weight and balance?
A force that tends to cause rotation. It is the product of the weight of an object in pounds
and the distance of the object from the datum in inches.
What is meant by the arm of an item installed in an aircraft?
The distance, in inches, between the center of gravity of the item and the datum.
Where do you find the arm of an item installed on an aircraft?
The Type Certificate Data Sheets for the aircraft.
What is meant by a moment index?
A moment divided by a constant such as 10, 100, or 1,000.
What is meant by the center of gravity range?
The distance in inches between the forward allowable center of gravity and the rearward
allowable center of gravity.
What is the significance of the empty weight center of gravity range of an
aircraft?
If the empty weight center of gravity falls within the EWCG range, the aircraft cannot be
legally loaded in such a way that it's loaded center of gravity will fall outside of the
allowable loaded CG range. Not all aircraft have an EWCG range.
Why is the empty weight center of gravity range not given in the Type Certificate
Data Sheets for some aircraft?
The empty weight center of gravity range is given only for aircraft that cannot be legally
loaded in such a way that the loaded center of gravity will fall outside of the allowable
limits.
What is meant by the mean aerodynamic chord(MAC)?
The chord of an imaginary airfoil that has the same aerodynamic characteristics of an
actual airfoil.
What is a loading envelope?
The enclosed area on a graph of an airplane's loaded weight and CG location. If lines
drawn from the weight and CG cross within this envelope the airplane is properly
loaded.
What is meant by permanent ballast for an aircraft?
Weight that is permanently installed in an aircraft to bring the empty weight center of
gravity into allowable limits.
Where must a record be kept of the current empty weight and the current center
of gravity of an aircraft?
,In the aircraft flight manual or weight and balance records required by 14 CFR §
23.1583.
Of what material are most low-pressure rigid fluid lines made?
1100-1/2 hard or 3003-1/2 hard aluminum alloy tubing.
Is the size of a rigid fluid line determined by its inside or its outside diameter?
Outside diameter.
When routing a fluid line parallel to an electrical wire bundle, which should be on
top?
Electrical wire bundle.
How can you distinguish an AN fluid line fitting from an AC fitting?
AN fitting has a shoulder between the end of the flare cone and the first thread. AC
fitting the threads extend all the way to the flare cone.
How tight should an MS flareless fitting be tightened?
Tighten the fitting by hand until it is snug, and then turn it with the wrench for 1/6-turn to
1/3-turn. Never turn it more the 1/3-turn.
What damage can be caused by overtightening an MS flareless fitting?
Overtightening drives the cutting edge of the sleeve deep into the tube and weakens it.
What kind of rigid tubing can be flared with a double flare?
5052-O and 6061-T aluminum alloy tubing in sizes from 1/8-inch to 3/8-inch OD.
Of what material should rigid fluid lines be made that carry high-pressure(3,000
psi or greater) hydraulic fluid?
Annealed or 1/4-hard corrosion-resistant steel.
What is the difference between the flare angle for aircraft and automotive fittings?
Aircraft fittings have 37º flare angle and automotive fittings use 45º.
What should be done to the end of a tube that is to be flared?
The cut end should be polished to remove any sharp edges that could cause the tubing
to crack.
What is the function of the lay line(the identification stripe) that runs the length of
a flexible hose?
To show if the line was twisted during installation.
Where are quick-disconnect fluid line couplings normally used in an aircraft
hydraulic system?
In the lines that connect the engine-driven pump into the hydraulic system.
Is the size of a flexible hose determined by its inside or its outside diameter?
Inside Diameter.
What is the minimum amount of slack that must be left when a flexible horse is
installed in an aircraft hydraulic system?
The hose should be at least 5% longer than the distance between fittings.
What is the principal advantage of Teflon hose for use in an aircraft hydraulic
system?
Teflon hose retains its high strength under conditions of high temperature.
How much pressure is used to proof-test a flexible hose assembly?
Varies but generally about two times operating pressure.
What is the proper type of nondestructive inspection to use for locating surface
cracks in an aluminum alloy casting or forging?
Zyglo or dye penetrant.
, What inspection method would be most appropriate for checking a nonferrous
metal part for intergranular corrosion?
Eddy Current inspection.
What inspection method would be most appropriate for checking the internal
structure of an airplane wing for corrosion?
X-Ray Inspection.
How does filiform corrosion usually appear on an aircraft structure?
As thread-like lines of puffiness under a film of polyurethane or other dense finish
system topcoats.
What inspection method would be most appropriate for checking a steel landing
gear component for stress cracks?
Magnetic Particle inspection.
What type of inspection is best suited for detecting a fault within a piece of
nonferrous metal?
Ultrasonic inspection.
Explain the procedure to use when making a dye penetrant inspection of a part.
Clean the part, apply the penetrant, and allow it to soak for recommended dwell time.
Remove the penetrant from the surface and apply the developer.
Why is it important that all parts be thoroughly cleaned before they are inspected
by the dye penetrant method?
Any grease or dirt in a fault will keep the penetrant from seeping into the fault.
Explain the procedure to use when performing a magnetic particle inspection of a
part.
Clean the part, magnetize it as directed by the service manual,flow the indicating
medium over the surface, and inspect under a blacklight. When the inspection is
complete, thoroughly demagnetize the part.
Why is it necessary to magnetize a part both circularly and longitudinally when
inspecting a steel part by the magnetic particle method?
To detect faults that extend across as well as lengthwise within the part.
Does circular magnetization detect parts that are across or lengthwise to the
part?
Lengthwise.
Why is it important that all engine parts which have been inspected by magnetic
particle method be completely demagnetized?
They will attract steel particles that are produced by engine wear and will cause damage
to bearing surfaces.
What is the principle of eddy current inspection?
A current is induced into the metal being tested by a test probe. The amount of induced
current is determined by the conductivity, mass, and permeability of the material, and
the presence of and faults or voids.
Why is it important that a piece of aluminum alloy be quenched immediately after
it is removed from the heat-treating oven?
To prevent intergranular corrosion.
What is meant by normalizing a piece of steel it has been welded or machined?
Normalizing will remove stresses locked into the material.
Explain the way a steel structure is normalized after it has been welded.
