AF203
The maximum slope of the grain for aviation-grade lumber is ___ to ___.
1 to 15
What is the maximum grain deviation for structural aircraft woods?
1 to 15
A splayed patch cannot be used in plywood skin that is more than ____-inch thick.
1/10
Aviation-quality wood is usually ___ sawn to minimize ____.
1/4, grain deviation and warping
When installing a new windshield, screw holes and edges should have about ___ inch clearance to allow for _____.
1/8, expansion and contration
The including angle for a twist drill used to drill acrylic plastic should be about ____.
150 degrees
What is the minimum umber of baseball stitches required per inch of sown repair?
4
The taper for a splayed patch is ____.
5 to 1
The taper for a splayed patch is?
5 to 1
What is the proper ratio for fiber to resin in a good quality composite repair?
60-40
What is the percentage that an aircraft fabric can deteriorate before you must remover the aircraft?
70 percent of the original strength of the fabric when it was new.
What is the ideal moisture content for wood?
8-12%
What is the minimum tensile strength of new grade a cotton.
80 psi
Resins have three time curing stages, they are?
A-mixed, B-chemical reaction, C-cured
Where is information found concerning acceptable species substitutions for wood splice materials used in aircraft repair?
AC43.13-1B
What is the name given to Aromatic Polymide fibers such as Kevlar?
Aramid
What defects would you look for in wood used for aircraft?
Compression, grain deviation, knots, and decay
What are the three basic types of aircraft covering systems?
Dacron, cotton, and fiberglass
The two common types of fiberglass are:
E-glass and S-glass
_____ plywood, covered with aircraft fabric may be used as the external skin on some aircraft.
Mahogany
How are two wood surfaces smoothed or prepped before gluing?
Planing or scraping
What wood is Superior for aircraft, and is used as the standard for all woods?
Sitka Spruce
When replacing grade A cotton fabric with Dacron (stits or ceconite), what must the technician have for the log book?
Supplemental Type Certificate
Besides fabric, what are the 4 other items that are used in fabric coverings system?
Surface tape, lacing cord, anti-tear strips, and dope
What is the principle behind the Maule Punch type fabric tester?
The tester is pushed directly down on the fabric where the dope has been removed and it reads in PSI.
The threads which run the length of the fabric as it comes off the bolt are referred to as the ____.
Warp
How do you shrink cotton fabric?
Water then Dope
In the US, the most frequently used transparent plastics for aircraft windows and windshields are:
acetate and acrylic
What is the most common plastic used in transparent applications today?
acrylic
What 4 methods are used to dissipate the electrical charge on composite structures?
aluminum wire wove into the top layer.
The procedures for mixing resin systems ____ very important.
are
whenever possible, composite materials should be ____ with wood when drilling.
backed up
What is the most common stitch used for hand sewing of aircraft fabrics.
baseball stitch
The ____ is at a 45 degree angle to the warp threads.
bias
____ are absorbent materials which are used to soak up the excess resins.
bleeder materials
_____ is good materials for softening acrylic plastic to glue it.
cementing
Firewalls may be made of ____ fiber composites to dissipate the heat.
ceramic
In addition to micro balloons, ____ and ____ may be used as filter material when repairing composite strucutres.
chopped fibers and metal
Mechanical pressure is used during the curing operation to:
compact the fiber layers.
If a damaged area in a honeycomb core is too large to be repaired by a potted repair, it may be cleaned out and filled with a plug made of ____ material or ____.
composite honeycomb, balsa wood
When you use Micro-Mesh, what is the correct order of application?
course grit, then progress to the finest grit
When a plastic material has thousand of tiny cracks in its surface, it is said to be _____..
crazed
Evaluations of the quality of wood must take into account the:
cut of wood, grain deviation, number of growth rings
separation of laminate layers or separation of the plies from the core material is called ___.
delamination
____ drills work on all types of composites ad have long life.
diamond
A cemented joint in acrylic plastic ____ shrink as it becomes hard.
does
Two commonly used types of glue for modern wood aircraft construction are:
epoxy resin and resorcinol glue
The three main parts of a fiber-reinforced composite are the:
fiber, matrix, interface
How do you shrink Dacron?
heat
How can you fix a windshield that you receive for a replacement and it doesn't quite fit the contour of the aircraft?
heat and reshape
What would aid in a faster cure time with a vacuum composite?
heat blanket
_____ are the preferred method of applying heat to cure a composite component for repair work.
heat blankets
Curing acrylic plastics at an elevated temperature is also referred to as ____.
heat treating
what is the advantage of using honeycomb in aircraft?
high strength to weight ratio
Three advantages offered by composites are:
high strength to weight ratio, weight reduction ratio, easy to form complex shapes and contours
Because of its flexibility and tensile properties, aramid is ideal for aircraft parts that are subject to____ and _____.
high stress and vibration
Sandwich construction core material may be made of:
honeycomb, foam, bulsa
A good quality cut in foam can be obtained by cutting the foam with what?
hot wire cutter
A ____ delamination repair involves injection of resin and micro-balloons into a damaged area.
injectible
The se of heat lamps to cure composite parts ___ recommended.
is not
Special brad point drills are available for drilling (what type) ___ composites.
kevlar
scissors with special steel blades with serrated edges are used to cut through ____ composite fabric.
kevlar.
The preferred way to make permanent repairs on composites is by?
laminating on new repair piles
Thermoplastic and thermosetting resins have ____ strength in themselves, and ___ reinforced with paper, cloth, or other filaments.
little, must be
The ____ points inside an aircraft structure are the most likely places for wood deterioration to begin.
lowest
What items of personal protective equipment are essential when working with composite chemicals?
mask, gloves, safety glasses
Chopped up fibers that are compressed together are often called ____.
mat
Radiography (x ray) ___ be used to detect water inside honeycomb core cells
may
A wing spar ____ be spliced under the fitting for a lift strut.
may not
____ are popular agent for use with thermosetting resins to give the resin good body with a minimum of weight.
micro balloons
How can you repair a scratch in an aircraft window?
micro-mesh
Acrylic windshields may be cleaned with _____ and water.
mild soap
Woven fabrics are ____ resistant to fiber breakout, delamination, and more damage tolerant than unidirectional materials.
more
damage to aircraft composite structure can be usually placed in one of these three categories
negligible
____ films and ___ fabrics are used between a composite repair and other bagging materials to allow excess matrix materials to flow through the upper surface.
parting, releasing
If you sand plastic too hard and fast what could happen?
plastic could craze
_____ is the working life of a resin batch while ____ is the storage life of unopened resin containers.
pot life, shelf life
If a puncture in the face of a honeycomb structure is minor (less than 1-inch), the repair may be made by ___.
potted repair
What is the purpose of tapering the flued repair in wood structures?
provides for more gluing are
What s a vacuum bagging used for in composite work.
removes air, excess resin and compresses fabric layers firmly together.
What are you required to do when repairing honeycomb that has delmaminated?
repair only one side, if that side is all that is damaged.
What is micro-mesh used for?
repairing damaged acrylic windows
Epoxy resin matrices are two-part systems consisting of a ____ and a ____, the ____ acts as a curing agent by initiating a chemical reaction to harden the epoxy.
resin, catalyst, catalyst
while sanding, drilling, or trimming composite materials a ____ must be worn to prevent breathing toxic fumes or dust.
respiator/mask
If wood comes up in small chunks rather than splinters when it is picked with the point of a knife blade, it may be considered to be ____.
rotted
Air-driven ___ are the best tools to use to remove damaged honeycomb core material from an aircraft structure.
routers
____ is the method that is usually used to remove advanced composite plies with the most control.
sanding
___ cutting is used to remove damaged material with a tapered cutout.
scarf
The tightly woven edge produced by the manufacturer to prevent the edges form unraveling is referred to as the ____ edge.
selvage
When inspecting a composite structure using the coin tap method, a dull thud may indicate?
separation of the laminates, delamination
When the ___ of a pre-preg fabric has expired it ___ be used for aircraft applications.
shelf life, may not
Sandpaper _____ be used to prepare a surface for gluing.
should not
You ____ use a cutting coolant when drilling into bonded honeycomb or foam core structure.
should not
aluminum fasteners ___ be used with carbon/graphite material.
should not
aluminum oxide sandpaper ___ be used to sand carbon/graphite materials.
should not
When sawing acrylic sheets, it is important to feed the material ____ to avoid ____.
slowly, overheating
When working with solvents and resins, it is important to take precautions against ____ and to always work in ___ areas.
sources of ignition, well ventilated
How do you repair a small crack in a plastic windshield?
stop drill then safety wire or bolts with washers and nuts on each side.
The most satisfactory way to store acrylic sheets is _____.
store them slightly away from the vertical at 10 degrees
what does acrylic smell like when it is burned?
sweet
The ____ is a simple method of detecting delamination close to the surface of a part.
tap test
a potted repair of minor damage to a structural component is considered to be ____ while repairs to non-structural parts are considered to be _____.
temporary, permanent
____ locates flaws by temperature variations at the surface of a damaged part.
thermography
The two categories of rein matrix system are:
thermoset and thermoplastic
What are the two natural classifications of plastic?
thermoset and thermoplastic
Generally, plastics may be classified as one of these types:
thermoset, thermoplastic
What type of agent is Micro-ballons?
thixotropic
What is a mold release used for?
to keep part from sticking to the mold
The strength of a fiber is ___ to the warp direction.
true
The warp of material is 90 degrees to the fill as it comes off the roll. True or false
true
Laminate construction consists of what?
two or more layers of fabric with a thermoset matrix
to detect internal flaws or areas of delamination a ___ may be used.
ultrasonic
Three common methods for inspecting and testing composite structures are:
ultrasonic.
Repairs made to advanced composites using materials and techniques that have traditionally be used for fiberglass repairs will result in a(n) ____ repair.
unairworthy
What is one cause of distortion in an aircraft window?
uneven damage removal
fabric woven with fibers in one direction, giving strength in that direction, are known as ____.
unidirectional
Soaking a sheet of acrylic plastic in boiling was is an _____ way of heating it into a formed shape.
unsatisfactory.
____ foam can be used with either epoxy or polyester resin.
urethane
____ is probably the most effective methods to apply pressure to a repair.
vacuum baggin
The best finish for internal wood structure is a good coat of high-quality ____.
varnish
Composite fabric material is considered to be the strongest in what direction?
warp
A(n) ____ is a tool which can be used to reference the orientation of the warp of the fiber.
warp clock
What is the precaution when working with transparent platics?
wear cotton gloves and leave the paper on it.
Acetone ___ soften acrylic plastic.
will
How can you reshape thermoset plastic to fit a compound curve?
you can not reshape it
