PREPWARE - Sheet Metal and Non-Metallic Structures (140)

(8041) Rivets are subjected to _______ by well-designed rivet joints

shear loads.

(8042) One Main diff. between *Lockbolt/ Huckbolt tension* & *shear* fasteners is

number of locking

collar grooves.

(8043) *Alloy 2117* rivets are heat treated

by the manufacturer

(pre-heat treatment not required)

(8044) General *rule* for *proper* rivet *diameter*?

3x thickness of

thickest sheet.

(8045) The *shop head* of a rivet should be?

1.5x the diameter

of the rivet shank

(8046) One Main *advantage* of *Hi-Lok fasteners* over earlier generations?

can be installed with ordinary hand tools.

(8047) The markings on a Dzus fastener head identifies

1) body diameter

2) type of head

3) length of the fastener.

The Dzus turnlock fastener consists of a stud, grommet, and receptacle.

(USE FOR 8048 & 8049)

(8048) A *Dzus* stud *length* is measured in?

_______________________________

(8049) A *Dzus* stud *diameter* is measured in?

hundredths of an inch.

________________________________

sixteenths of an inch.

(8050) Threaded rivets (aka Rivnuts) are used to?

attach parts

or components

to sheet metal

w/screws

(8051) Cherrymax and Olympic-Lok rivets are installed by

a pulling tool.

(8052) Hole filling fasteners shouldn't be used in composite structures due to the

possibility of causing delamination.

(8053) Metal fasteners used with carbon or graphite composite structures

must be constructed w/

titanium or corrosion resistant steel.

(8054) Modern aircrafts, use *Sandwich panels* because it's *Metal honeycomb construction* has

high

strength to weight

ratio.

(8055) *(1)* When performing a ring (coin tap) test on composite structures, a change in sound may be due to damage or to transition to a different internal structure. *(2)* The extent of separation damage in composite structures is most accurately measured by a ring (coin tap) test.

*Regarding the above statements*

only No. 1 is true.

(8056) *Fiberglass/honeycomb* structures are *inspected* for *entrapped water* by what methods?

x-ray

&

backlighting

(8057) When balsa wood is used to replace a damaged honeycomb core, the plug should be cut so that

the *grain* is *perpendicular* to the *skin*.

(8058) When repairing puncture-damage of a metal faced laminated honeycomb panel, edges of the doubler should be tapered to

100x the thickness

of the metal.

(8059) Best way to assure properly prepared matrix resin was achieved?

mix enough for

a test sample.

(8060) *Acoustic emission testing detects* defects in composite materials by

picking up any present deterioration 'noise'

(8061) Precaution taken to prevent corrosion (inside a repaired metal honeycomb structure?)

(1)Prime repair w/ corrosion inhibitor &

(2) seal from the atm

(8062) One method to inspect a damaged, laminated fiberglass structure is to

strip paint on dmg area

&

shine strong light thru it.

(8063) When inspecting a composite panel using the ring test/tapping method, a dull thud may indicate?

separation of the laminates.

(8064) What are *benefits of using microballoons*, when making repairs to laminated honeycomb panels?

1. Greater concentration of resin in edges and corners.

2. Improved strength to weight ratio.

3. Less density

4. Lower stress concentrations

2, 3, and 4.

(8065) The *length of time* that a *catalyzed resin* will *remain* in a *workable state* is called?

pot life.

(8066) *Plastic material* capable of *softening/flowing when reheated* is a?

thermoplastic.

(8067) *Fiberglass Classification* for *high tensile strength*

S-glass.

(8068) What is an *identifying characteristic* of *acrylic plastics?*

Zinc chloride will have

no effect.

(8069) Superficial scars, scratches, surface abrasion, or rain erosion on fiberglass laminates can generally be repaired by applying?

one or more coats of suitable resin (room-temperature catalyzed) to the surface.

(8070) *Fiberglass class* for reinforcement material

( _ resistivity & common)

E-glass.

(8071) Honeycomb damages less than ______ can be potted-compound repaired.

1 inch in diameter.

(8072) What direction is Composite fabric material considered strongest?

Warp.

(8073)-What *reference tool* is used to determine how the fiber is *to be oriented* for a particular ply of fabric?

Warp clock (or compass).

(8074)-The strength & stiffness of a properly constructed composite buildup depends primarily on?

the orientation of the plies to the load direction.

(8075)-Which *fiber to resin ratio* for adv composite wet lay-ups, is the *best for strength*?

60:40.

(8076) The material layer used w/in the vacuum bag pressure system to absorb excess resin during curing?

Bleeder.

(8077)-Proper pre-preg composite lay-up curing is generally accomplished by

1. applying external heat.

2. room temperature exposure.

3. adding a catalyst or curing agent to the resin.

4. applying pressure.

1 and 4.

(8078)-When repairing large, flat surfaces with polyester resins, warping of the surface is likely to occur. One method of reducing the amount of warpage is to?

use short strips of fiberglass in the bonded repair.

(8079) Cleaning the fiberglass area to be repaired is essential for a good bond. *_ _ _ shoulda be used for final cleaning*

MEK

(methyl ethyl ketone).

(8080)-When necessary, what type of cutting fluid is usually acceptable for machining composite laminates?

Water only.

(8081)-Fiberglass laminate damage not exceeding the first layer or ply can be repaired by?

filling with a putty consisting of a compatible resin and clean, short glass fibers.

(8082)-Fiberglass damage that extends completely through a laminated sandwich structure?

may be repaired.

(8083)-Fiberglass laminate damage that extends completely through one facing and into the core?

requires the replacement of the damaged core and facing.

(8084)-Repairing advanced composites using materials and techniques traditionally used for fiberglass repairs is likely to result in?

an unairworthy repair.

(8085)-The preferred way to make permanent repairs on composites is by?

laminating on new repair plies.

(8086)-Which of the following, when added to wet resins, provide strength for the repair of damaged fastener holes in composite panels?

1. Microballoons.

2. Flox.

3. Chopped fibers.

2 and 3.

(8087)-The part of a replacement honeycomb core that must line up with the adjacent original is the?

ribbon direction.

(8088)-Which are generally characteristics of aramid fiber (Kevlar) composites?

1. High tensile strength.

2. Flexibility.

3. Stiffness.

4. Corrosive effect in contact with aluminum.

5. Ability to conduct electricity.

1 and 2.

(8089)-Which are general characteristics of carbon/graphite fiber composites?

1. Flexibility.

2. Stiffness.

3. High compressive strength.

4. Corrosive effect in contact with aluminum.

5. Ability to conduct electricity.

2, 3, and 4.

(8090)-If an aircraft's transparent plastic enclosures exhibit fine cracks which may extend in a network over or under the surface or through the plastic, the plastic is said to be?

crazing.

(8091) *When installing transparent plastic enclosures* which are retained by bolts extending through the plastic material and self-locking nuts, *the nuts should be*?

tightened to a firm fit, then backed off one full turn.

(8092) A new safety belt installation must conform to strength requirements of ?

TSO C22.

(8093)-What is considered good practice concerning the installation of acrylic plastics?

When rivets are used, adequate spacer or other satisfactory means to prevent excessive tightening of the frame to the plastic should be provided.

(8094) The *coefficient of expansion* of most plastic enclosure materials is?

greater than both

steel & aluminum.

(8095) If no scratches are visible after cleaning transparent plastic enclosure materials, the surfaces should be?

covered with a

thin coat of wax.

(8096) *Cabin upholstery* materials must be _________ in standard category airplanes

at least

flame resistant.

(8097) What is the most common method of cementing transparent plastics?

Soak method.

(8098) What *type of bit* should be used to drill holes in *Plexiglass*?

A specially modified

twist drill.

(8098.1) What *type of bit* is best to drill an aramid fiber *(Kevlar)* composite laminate?

Carbide W-Point.

(8099) What is the purpose of a *gusset* or gusset plate?

To join and reinforce intersecting structural members.

(8100) Select the *alternative function* of the flute section of a twist drill.

Forms

the cutting edges

of the drill point.

(8101) How many MS20470 AD-4-6 rivets will be required to attach a 10x5-in plate?

1.) using a single row of rivets,

2.) minimum edge distance,

3.) 4D spacing?

56

(8102) Longitudinal (fore and aft) structural members of a semi-monocoque fuselage are called?

longerons

&

stringers.

(8103) Shallow scratches in sheet metal may be repaired by?

burnishing.

(8104) What should be the included angle of a twist drill for soft metals?

90°.

(8105)-When comparing the machining techniques for stainless steel sheet material to those for aluminum alloy sheet, it is normally considered good practice to drill the stainless steel at a?

lower speed with more pressure applied to the drill.

(8106)-A single-lap sheet splice is to be used to repair a section of damaged aluminum skin. If a double row of 1/8-inch rivets is used, the minimum allowable overlap will be?

13/16 inch.

(8106.1)-What is the minimum edge distance allowed for aluminum alloy single lap sheet splices containing a single row of rivets as compared to a joint with multiple rows, all rivets being equal in diameter?

The minimum edge distance for the single row is equal to that for the multiple row.

(8107)-Which statement is true regarding the inspection of a stressed skin metal wing assembly known to have been critically loaded?

If genuine rivet tipping has occurred, groups of consecutive rivet heads will be tipped in the same direction.

(8108) What is the minimum edge distance for aircraft rivets?

2x the rivet shank

diameter

(8109) When drilling stainless steel, the drill used should have an included angle of?

140°

and

turn at a low speed.

(8110) What is the min. spacing for a single row of aircraft rivets?

3x the rivet shank

diamter

(8111) (Refer to Fig.1) What rivet will accurately fit the conical depression made by a 100° countersink?

1

(8112) Which is the correct use of a file?

*Only apply pressure on the forward stroke*

except on soft metals (ie. lead or aluminum)

(8113) What *factor* permits *machine countersinking* when flush riveting?

Material thickness

*is greater than*

rivet head thickness

(8114) When repairing a small hole on a metal stressed skin, consider ________ in the patch design.

the shear strength

of the riveted joint.

(8115) Using a reamer to finish a drilled hole to the correct size, What procedure is correct?

Turn the reamer

only in the cutting direction.

(8116) Repairs or splices involving stringers on the lower surface of stressed skin metal wings are usually?

*permitted but are normally more critical* in reference to strength in tension than similar repairs to the upper surface.

(8117) When *straightening 2024-T4*, you should?

straighten cold and reinforce.

(8118) Aircrafts use *clad aluminum alloys* because

it's less corrosive than uncoated aluminum alloys.

(8119) What statement is true regarding a cantilever wing?

No external bracing

is needed.

(8120) Aircraft structural units built from sheet metal are normally

repairable

(using approved methods)

(8121) What factor determines the minimum space between rivets?

diameter of the rivets being used.

(8122) What should be the *included angle* of a *twist drill* for hard metal?

118°

(8123) Parts fabricated from Alclad 2024-T3 aluminum sheet stock must have all?

minimum scratches, kinks, tool marks, nicks, etc.

(8124) The monocoque fuselage relies largely on the strength of?

skin

or

covering

(8125) What semi-monocoque fuselage *parts prevents* tension and compression from *bending the fuselage*?

Longerons

&

Stringers

(8126) *Rivet gauge*, or transverse pitch, is the distance between the

centers of rivets in adjacent rows.

(8127) *Rivet pitch* is the distance between the

centers of adjacent rivets in the same row.

(8128) (Refer to Figure 2.) Select the preferred drawing for proper countersinking.

1

(8129) Black 'smoky' residue from rivets indicate what?

Fretting corrosion between rivets & skin.

(8130) *Identifying marks* on rivets heads *indicate*?

specific rivet alloy

(8131) MS20470D rivets *obtain full shear strength*

only after a period

of age hardening.

(8132)-What *isn't considered* when minimum rivet spacing?

Rivet length.

(8133) 2017 & 2024 aluminum alloy rivets *Refrigerated after heat treatment* does what?

retard

age

hardening.

(8134) Under certain conditions, *type A rivets* are *not used* because of their?

low strength characteristics.

(8135) A rivet set used to drive MS20470 rivets should?

have a

*slightly greater radius*

than the rivet head.

(8136) D/DD heat treated rivets *not used in certain time frame* after being heat treated or refrigerated,

must be *reheat treated* before use.

(8137) MS*20430*AD-4-8

has rivet dimensions of?

1/8 inch diameter

1/2 inch long

(8138) What No. indicates the *primary alloying agent* in *2024-T3*?

2