NON METALLIC STRUCTURE (2)

when repairing large, tiat surtaces with polyester resins, warping of the surface is likely to occur. One method of reducing the amount of warpage is to. add an extra amount of catalyst to the resin. use short strips of fiberglass in the bonded repair. covered with a thin coat of wax.

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

The classification for fiberglass reinforcement material that has high resistivity and is the most common is. E-glass. S-glass. G-glass.

Fungicide and mildewicide additives are important for fabric covered aircraft, such as. cotton and dacron. cotton and linen. glass and linen.

Which of the following are generally characteristic of carbon/ graphite fiber composites?. Flexibility, high compressive strength, and corrosive effect in contact with aluminum. Stiffness, high compressive strength, and corrosive effect in contact with aluminum. Ability to conduct electricity.

When testing the strength of Grade A cotton fabric covering an aircraft that requires only intermediate grade, the minimum acceptable strength the fabric must have is. 70 percent of its original strength. 70 percent of the original strength for intermediate fabric. 56 pounds per inch warp and fill.

Which of the following are generally characteristic of aramid fiber (Kevlar) composites?. High tensile strength and flexibility. High tensile strength and stiffness. Corrosive effect in contact with aluminum and ability to conduct electricity.

Compression failures in wood aircraft structures are characterized by buckling of the fibers that appear as streaks on the surface. at right angles to the growth rings. parallel to the grain. at right angles to the grain.

When necessary, what type of cutting fluid is usually acceptable for machining composite laminates?. Water soluble oil. Water displacing oil. Water only.

Any wooden member that has been overstressed is subject to which type of failure?. Stretch. Compression. Torsion.

On a semi-monocoque fuselage, the skin is reinforced by longitudinal structural members called. beams and struts. longerons and stringers. formers and bulkheads.

Moisture, mildew, chemicals, and acids have no effect on. glass fabric. cotton fabric. polyester fabric.

The strength and stiffness of a properly constructed composite buildup depends primarily on. a 60 percent matrix to 40 percent fiber ratio. the orientation of the plies to the load direction. the ability of the fibers to transfer stress to the matrix.

de mas. no. si. no.

A piece of sheet metal is bent to a certain radius. The curvature of the bend is referred to as the. bend allowance. neutral line. bend radius.

Repairing advanced composites using materials and techniques traditionally used for fiberglass repairs is likely to result in. restored strength and flexibility. slightly stronger strength to weight ratio. an unairworthy repair.

Which statement concerning wood decay is correct?. Decay that appears to be mineral streaks is acceptable. A limited amount of decay along the beveled edges of unrouted beams is acceptable. Any form or amount of decay is not permitted.

Which statement is true regarding a cantilever wing?. It has nonadjustable lift struts. No external bracing is needed. It requires only one lift strut on each side.

Which of the following conditions will determine acceptance of wood with mineral streaks?. Careful inspection fails to reveal any decay. They produce only a small effect on grain direction. Local irregularities do not exceed limitations specified for spiral and diagonal grain.

Which fiber to resin (percent) ratio for advanced composite wet lay-ups is generally considered the best for strength?. 40:60. 50:50. 60:40.

Which of the following are benefits of using microballoons when making repairs to laminated honeycomb panels?. Improved strength-to-weight ratio, less density, and lower stress concentrations. Greater concentrations of resin in edges and corners. Less density and improved strength-to-weight ratio.