Airframe & General Oral Exam (Jeppesen) || with Error-free
Answers.
What is the function of a vortex generator? correct answers It is designed to delay of prevent
separation of the boundary layer.
What are the three axes of an airplane? correct answers Longitudinal, lateral, and vertical.
What are the three primary flight controls of an aircraft? correct answers The ailerons,
elevators, and rudder.
Name several secondary flight controls and describe their general purpose? correct answers
Secondary flight controls consist of various types of trim tabs such as balance tabs, anti-servo
and servo tabs, and spring tabs. Their function is to assist the pilot in moving the controls and
to trim the aircraft to fly hands-off.
Name several types of auxiliary flight controls and describe their general purpose? correct
answers The auxiliary flight controls consist of the various high-lift devices used during low-
speed flight such as leading and trailing edge flaps, slats, slots, speed brakes, etc.
What is a servo trim tab (3)? correct answers (1) An auxiliary control thats (2) Positioned by
movement of a primary control and (3) Designed to create aerodynamic forces to help move
control surface.
What is a spring tab (2)? correct answers (1) Auxiliary control which (2) aids in the
movement of a primary control at high speeds when control forces become too high.
What is a balance trim tab (3)? correct answers (1) Auxiliary control that (2) creates
aerodynamic forces to move control surface and is (3) positioned by control rod connected to
fixed surface on same side as horn and tab
What are four most common types of high lift devices? correct answers Leading and trailing
edge flaps, slats, and slots.
Describe some of the tools used to check control surface travel? correct answers A universal
propeller protractor or special control surface protractor.
Name three mechanical methods by which flight control systems may be actuated. correct
answers Cables, push-pull rods, and torque tubes.
What is a fairlead? correct answers It is a device to prevent a cable from rubbing on the
aircraft structure.
What are the most likely places for a control cable to wear or break? correct answers Where
the cables pass over pulleys or through fairleads.
What information is required before a cable rigging chart can be used? correct answers The
ambient temperature and the cable size.
,What is the function of a cable tension regulator? correct answers It automatically adjusts the
cable tension to compensate for expansion and contraction in the aircraft structure.
Describe the function of rotorcraft collective pitch control. correct answers The collective
control causes each rotor blade to change its pitch angle by the same amount, thus increasing
or decreasing the lift produced by the rotor.
Describe the function of a rotorcraft cyclic pitch control. correct answers The cyclic control
tilts the main rotor disc by changing the pitch angle of each rotor blade during its cycle of
rotation, which causes the helicopter to move in the direction the rotor tilts.
What mechanism is most commonly used to compensate for the torque produced by the main
rotor of a helicopter? correct answers The tail (or anti-torque) rotor.
How is the amount of thrust produced by the tail rotor controlled? correct answers By moving
the foot pedals.
Why should a control surface be locked when an aircraft is parked? correct answers To
prevent damage from the wind.
What is the major type of damage to aluminum structures that is caused by exposure to the
weather? correct answers Corrosion.
Name several method for forming sheet metal. correct answers Bending (folding), bumping,
stretching, shrinking, and crimping.
What are the dimensions of a properly formed rivet head? correct answers The head should
be 1 & 1/2 times the shank diameter in width and 1/2 the shank diameter in height.
Describe the markings found on the heads of A, B, D, AD, and DD rivets? correct answers A
rivets are plain, B rivets have a cross, D rivets have a raised dot, AD rivets have a dimple,
and DD rivets have a double dash.
What happens to the stem of a self-plugging (friction lock) rivet when the rivet is installed?
correct answers The stem is pulled until it snaps off and the remaining projecting part is
trimmed flush with the head.
Name at least three types of self-plugging mechanical lock rivets. correct answers
CherryMAX, CherryLOCK, OLYMPIC-LOK, and HuckLok.
What is the difference between the tools required to pull a CherryLOCK rivet and a
CherryMAX rivet? correct answers CherryLock rivets require a tool for each different size
and head shape, while one pulling tool will set any size CherryMAX rivet.
Which of the five stresses is the most common cause of rivet failure? correct answers Shear.
If a 2024 rivet must be replaced with a 2117 rivet, how do you determine the size to be used?
correct answers For 5/32" or smaller diameter, use the next larger size 2117 rivet, assuming
that the edge distance and spacing meet the minimum requirements.
,Describe the process for determining the total length of a solid rivet for a particular
installation. correct answers Add the grip length or add the thickness of the materials being
joined plus 1.5 times the rivet diameter.
What minimum edge distance and spacing should be used for a single row of protruding head
rivets? correct answers Not less than two rivet diameters from the edge and not less than three
rivet diameters apart.
How can a mechanic determine whether the countersink for a flush rivet should be dimpled
or drilled? correct answers By the thickness of the top sheet; thin sheets are dimpled while
thick sheets may be countersunk.
What action is taken to prevent cracks from forming while dimpling magnesium or some hard
sheet metals? correct answers Hot dimpling equipment is used to preheat and soften the metal
before the dimple is formed.
What type of damage can occur when using a rivet set that does not properly fit the rivet?
correct answers If the radius of the set is too small, the rivet head may be damaged, whereas a
set with an over-sized radius may cause damage to the sheet metal.
Why is it important to use the proper size and weight bucking bar when performing sheet
metal riveting? correct answers If a bucking bar is too large or heavy it may be difficult to
control and may cause damage to the surrounding structure, whereas a bucking bar that is too
light will not properly upset the rivet before work hardening occurs.
What procedures should be followed to properly remove a solid-shank rivet? correct answers
Center punch the rivet and then drill just to the base of the rivet head with the same size or
one size smaller drill. Once drilled, use a pin punch to tip off the rivet head and drive the
remaining shank out of the hole while supporting the surrounding metal.
What are the two special calculations that must be made bending sheet metal? correct
answers Bend allowance and setback.
What factors must be considered in order to determine setback? correct answers The
thickness of the metal and the bend radius.
What is done to a corner where two bends intersect to prevent cracking? correct answers
Relief holes are drilled in the corner.
What are the two reasons for installing a lightening hole in the sheet metal? correct answers
Lightening holes reduce the weight and increase stiffness.
Describe a joggle and explain its function. correct answers A joggle is an offset formed at an
intersection of two or more sheets of metal to allow the multiple sheets to be stacked flat
against each other.
When repairing an all-metal aircraft, how do you determine what metal should be used?
correct answers Always use metal of the same type and thickness as the original structure.
, What are three forms of wood commonly used in aircraft construction? correct answers Solid,
laminated, and plywood.
What type of wood should be used when splicing or reinforcing plywood webs? correct
answers The same type of plywood as originally used.
Name at least four different types of defects found in wood? correct answers Knots, checks,
splits, pitch pockets, cross grain, curly grain, decay, dry rot, etc..
Can a section of wood containing a hard knot be used? correct answers Yes, within specified
limits.
What type of glue may have been used in older wooden aircraft construction that requires
careful inspection to detect deterioration? correct answers Casein glue.
What are the three types of glue used in modern aircraft construction and repair? correct
answers Resorcinol glue, Phenol-formaldehyde glue, and epoxy resin glue.
Is compression wood acceptable for structural repairs? correct answers No.
Why should the various pieces of wood being joined be kept in the same room for at least 24
hours prior to joining? correct answers To allow the moisture content to equalize, thereby
minimizing dimensional changes in the wood.
Why is it important to consider the open-assembly time when gluing wooden structures?
correct answers If the maximum open-assembly time is exceeded, the joint may fail since the
glue may begin setting up before the joint is assembled.
Why is it important to apply the proper clamping pressure to a glue joint? correct answers
Clamping forces air out of the joint, brings the wood surfaces together evenly and is, in part,
responsible for the strength of the glue line.
Describe some of the methods used to apply pressure to glue joints. correct answers Clamps,
nailing strips, power presses, brads, nails, and small screws.
What minimum curing temperature should be observed when joining wood with various
adhesives? correct answers 70 degrees Fahrenheit or as specified by the glue manufacturer.
When inspecting wood structures, why might it be important to consider stains and discolored
area? correct answers Stains and discoloration usually accompany decay and/or rot.
Describe the acceptable methods used to repair elongated bolts holes found in wooden wing
spar. correct answers Remove the section containing the elongated holes and splice in a new
section or replace the entire spar.
What type of joint is used to splice a solid or rectangular wood spar? correct answers A scarf
joint.
In what areas are splices to a wood spar prohibited? correct answers Under an attachment
fitting for the wing root, landing gear, engine-mount, or lift-&-interplane strut fitting.
Answers.
What is the function of a vortex generator? correct answers It is designed to delay of prevent
separation of the boundary layer.
What are the three axes of an airplane? correct answers Longitudinal, lateral, and vertical.
What are the three primary flight controls of an aircraft? correct answers The ailerons,
elevators, and rudder.
Name several secondary flight controls and describe their general purpose? correct answers
Secondary flight controls consist of various types of trim tabs such as balance tabs, anti-servo
and servo tabs, and spring tabs. Their function is to assist the pilot in moving the controls and
to trim the aircraft to fly hands-off.
Name several types of auxiliary flight controls and describe their general purpose? correct
answers The auxiliary flight controls consist of the various high-lift devices used during low-
speed flight such as leading and trailing edge flaps, slats, slots, speed brakes, etc.
What is a servo trim tab (3)? correct answers (1) An auxiliary control thats (2) Positioned by
movement of a primary control and (3) Designed to create aerodynamic forces to help move
control surface.
What is a spring tab (2)? correct answers (1) Auxiliary control which (2) aids in the
movement of a primary control at high speeds when control forces become too high.
What is a balance trim tab (3)? correct answers (1) Auxiliary control that (2) creates
aerodynamic forces to move control surface and is (3) positioned by control rod connected to
fixed surface on same side as horn and tab
What are four most common types of high lift devices? correct answers Leading and trailing
edge flaps, slats, and slots.
Describe some of the tools used to check control surface travel? correct answers A universal
propeller protractor or special control surface protractor.
Name three mechanical methods by which flight control systems may be actuated. correct
answers Cables, push-pull rods, and torque tubes.
What is a fairlead? correct answers It is a device to prevent a cable from rubbing on the
aircraft structure.
What are the most likely places for a control cable to wear or break? correct answers Where
the cables pass over pulleys or through fairleads.
What information is required before a cable rigging chart can be used? correct answers The
ambient temperature and the cable size.
,What is the function of a cable tension regulator? correct answers It automatically adjusts the
cable tension to compensate for expansion and contraction in the aircraft structure.
Describe the function of rotorcraft collective pitch control. correct answers The collective
control causes each rotor blade to change its pitch angle by the same amount, thus increasing
or decreasing the lift produced by the rotor.
Describe the function of a rotorcraft cyclic pitch control. correct answers The cyclic control
tilts the main rotor disc by changing the pitch angle of each rotor blade during its cycle of
rotation, which causes the helicopter to move in the direction the rotor tilts.
What mechanism is most commonly used to compensate for the torque produced by the main
rotor of a helicopter? correct answers The tail (or anti-torque) rotor.
How is the amount of thrust produced by the tail rotor controlled? correct answers By moving
the foot pedals.
Why should a control surface be locked when an aircraft is parked? correct answers To
prevent damage from the wind.
What is the major type of damage to aluminum structures that is caused by exposure to the
weather? correct answers Corrosion.
Name several method for forming sheet metal. correct answers Bending (folding), bumping,
stretching, shrinking, and crimping.
What are the dimensions of a properly formed rivet head? correct answers The head should
be 1 & 1/2 times the shank diameter in width and 1/2 the shank diameter in height.
Describe the markings found on the heads of A, B, D, AD, and DD rivets? correct answers A
rivets are plain, B rivets have a cross, D rivets have a raised dot, AD rivets have a dimple,
and DD rivets have a double dash.
What happens to the stem of a self-plugging (friction lock) rivet when the rivet is installed?
correct answers The stem is pulled until it snaps off and the remaining projecting part is
trimmed flush with the head.
Name at least three types of self-plugging mechanical lock rivets. correct answers
CherryMAX, CherryLOCK, OLYMPIC-LOK, and HuckLok.
What is the difference between the tools required to pull a CherryLOCK rivet and a
CherryMAX rivet? correct answers CherryLock rivets require a tool for each different size
and head shape, while one pulling tool will set any size CherryMAX rivet.
Which of the five stresses is the most common cause of rivet failure? correct answers Shear.
If a 2024 rivet must be replaced with a 2117 rivet, how do you determine the size to be used?
correct answers For 5/32" or smaller diameter, use the next larger size 2117 rivet, assuming
that the edge distance and spacing meet the minimum requirements.
,Describe the process for determining the total length of a solid rivet for a particular
installation. correct answers Add the grip length or add the thickness of the materials being
joined plus 1.5 times the rivet diameter.
What minimum edge distance and spacing should be used for a single row of protruding head
rivets? correct answers Not less than two rivet diameters from the edge and not less than three
rivet diameters apart.
How can a mechanic determine whether the countersink for a flush rivet should be dimpled
or drilled? correct answers By the thickness of the top sheet; thin sheets are dimpled while
thick sheets may be countersunk.
What action is taken to prevent cracks from forming while dimpling magnesium or some hard
sheet metals? correct answers Hot dimpling equipment is used to preheat and soften the metal
before the dimple is formed.
What type of damage can occur when using a rivet set that does not properly fit the rivet?
correct answers If the radius of the set is too small, the rivet head may be damaged, whereas a
set with an over-sized radius may cause damage to the sheet metal.
Why is it important to use the proper size and weight bucking bar when performing sheet
metal riveting? correct answers If a bucking bar is too large or heavy it may be difficult to
control and may cause damage to the surrounding structure, whereas a bucking bar that is too
light will not properly upset the rivet before work hardening occurs.
What procedures should be followed to properly remove a solid-shank rivet? correct answers
Center punch the rivet and then drill just to the base of the rivet head with the same size or
one size smaller drill. Once drilled, use a pin punch to tip off the rivet head and drive the
remaining shank out of the hole while supporting the surrounding metal.
What are the two special calculations that must be made bending sheet metal? correct
answers Bend allowance and setback.
What factors must be considered in order to determine setback? correct answers The
thickness of the metal and the bend radius.
What is done to a corner where two bends intersect to prevent cracking? correct answers
Relief holes are drilled in the corner.
What are the two reasons for installing a lightening hole in the sheet metal? correct answers
Lightening holes reduce the weight and increase stiffness.
Describe a joggle and explain its function. correct answers A joggle is an offset formed at an
intersection of two or more sheets of metal to allow the multiple sheets to be stacked flat
against each other.
When repairing an all-metal aircraft, how do you determine what metal should be used?
correct answers Always use metal of the same type and thickness as the original structure.
, What are three forms of wood commonly used in aircraft construction? correct answers Solid,
laminated, and plywood.
What type of wood should be used when splicing or reinforcing plywood webs? correct
answers The same type of plywood as originally used.
Name at least four different types of defects found in wood? correct answers Knots, checks,
splits, pitch pockets, cross grain, curly grain, decay, dry rot, etc..
Can a section of wood containing a hard knot be used? correct answers Yes, within specified
limits.
What type of glue may have been used in older wooden aircraft construction that requires
careful inspection to detect deterioration? correct answers Casein glue.
What are the three types of glue used in modern aircraft construction and repair? correct
answers Resorcinol glue, Phenol-formaldehyde glue, and epoxy resin glue.
Is compression wood acceptable for structural repairs? correct answers No.
Why should the various pieces of wood being joined be kept in the same room for at least 24
hours prior to joining? correct answers To allow the moisture content to equalize, thereby
minimizing dimensional changes in the wood.
Why is it important to consider the open-assembly time when gluing wooden structures?
correct answers If the maximum open-assembly time is exceeded, the joint may fail since the
glue may begin setting up before the joint is assembled.
Why is it important to apply the proper clamping pressure to a glue joint? correct answers
Clamping forces air out of the joint, brings the wood surfaces together evenly and is, in part,
responsible for the strength of the glue line.
Describe some of the methods used to apply pressure to glue joints. correct answers Clamps,
nailing strips, power presses, brads, nails, and small screws.
What minimum curing temperature should be observed when joining wood with various
adhesives? correct answers 70 degrees Fahrenheit or as specified by the glue manufacturer.
When inspecting wood structures, why might it be important to consider stains and discolored
area? correct answers Stains and discoloration usually accompany decay and/or rot.
Describe the acceptable methods used to repair elongated bolts holes found in wooden wing
spar. correct answers Remove the section containing the elongated holes and splice in a new
section or replace the entire spar.
What type of joint is used to splice a solid or rectangular wood spar? correct answers A scarf
joint.
In what areas are splices to a wood spar prohibited? correct answers Under an attachment
fitting for the wing root, landing gear, engine-mount, or lift-&-interplane strut fitting.
