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Green explanations indicate questions you answered correctly. Red explanations indicate questions you answered incorrectly. Score 0.0%. You answered 0 out of 1056 correctly. View Performance Chart (/print_perf_chart?quiz_id=9273616) Save Missed Questions 1. When selecting a welding rod, one of the most important factor...
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radius of the neutral axis plus one-half the thickness of the metal being formed. The bend radius of a piece of sheet metal is the radius of the inside of the bend. 2 of 252 2/17/26, 13:31 8. A sheet metal repair is to be made using two pieces of 0.0625-inch aluminum riveted together. All rivet holes are drilled for 1/...
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The closest rivet to this is one with a diameter of 1/8 inch (0.125 inch). A 1/8-inch rivet should extend through the material for 3/16 inch, or 0.1875 inch. The total length of the rivet must be 0.064 + 0.1875, or 0.2515 inch. We would choose an MS20470AD-4-4 rivet. This is a universal head rivet, 1/8 inch in diameter...
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started by tapping the aluminum in the center until it touches the bottom of the mold and then working out in all directions. When using the bumping operation to form a compound curve in a piece of soft aluminum, use light blows of the mallet to work the material down gradually from the edges. Remember that the object ...
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two times the rivet length. C. three times the thickness of the thickest sheet. A rule of thumb for determining the rivet diameter to be used for repairing aircraft sheet metal is to use a rivet whose diameter is approximately three times the thickness of the thickest sheet being joined. 29. (Refer to Figure 2.) Select...
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The material on the outside of a curve stretches, while the material on the inside of the curve compresses. There is a location near the middle of the metal thickness that neither shrinks nor stretches. This is called the neutral line, or the neutral axis, of the material. 37. Where should the flux be applied when oxya...
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When repairing puncture-type damage to a metal-faced laminated honeycomb panel, the edges of the doubler should be tapered to A. two times the thickness of the metal. B. 100 times the thickness of the metal. C. whatever is desired for a neat, clean appearance. When repairing puncture-type damage to a metal-faced lamina...
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The total length of the rivet seams is 28 inches. If the rivets are spaced every 1/2 inch (4D spacing), 56 rivets are needed. 12 of 252 2/17/26, 13:31 50. When welding or cutting, the acetylene pressure gauge should never be set higher than A. 15 psi. B. 20 psi. C. 25 psi. The acetylene pressure gauge should never be s...
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But for all practical purposes, the neutral axis of a bend can be considered to be the bend radius, plus one-half of the stock thickness. 56. A very thin and pointed tip on a soldering copper is undesirable because it will A. transfer too much heat to the work. B. have a tendency to overheat and become brittle. C. cool...
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Type A rivets (commercially pure aluminum rivets) are not used for aircraft structural repair because of their low-strength characteristics. 64. What is generally the best procedure to use when removing a solid shank rivet? A. Drill through the manufactured head and shank with a shank size drill and remove the rivet wi...
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The oxyacetylene flame for silver soldering should be A neutral oxyacetylene flame is normally used for silver soldering. A flame having a slight excess of acetylene may sometimes be used, but it must be soft, not harsh. 71. In gas welding, the amount of heat applied to the material being welded is controlled by the A....
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Thick aluminum plates are preheated to reduce the internal strains caused by the large amount of expansion when the thick plates are heated. 79. Alloy 2117 rivets are heat treated A. by the manufacturer and do not require heat treatment before being driven. B. by the manufacturer but require reheat treatment before bei...
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One precaution to be observed when riveting together dissimilar metals is to place a nonconductive separator between the two surfaces. This separator prevents the migration of electrons between the areas of electrode potential difference. 85. Cylinders used to transport and store acetylene A. are pressure tested to 3,0...
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If the direction of reamer motion is reversed, the reamer will be seriously dulled. 92. The length of a rivet to be used to join a sheet of .032-inch and .064-inch aluminum alloy should be equal to A. two times the rivet diameter plus .064 inch. B. one and one-half times the rivet diameter plus .096 inch. C. three time...
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What should be the included angle of a twist drill for soft metals? For drilling soft metals, an included angle of about 90° (45° either side of center) is suitable. For normal metals, an angle of 118° (59° on either side of center) is considered the standard lip angle. 23 of 252 2/17/26, 13:31 98. (Refer to Figure 7.)...
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permitted only if the damage does not exceed 6 inches in any direction. C. permitted but are normally more critical in reference to strength in tension than similar repairs to the upper surface. Repairs or splices to the stringers on the lower surface of a stressed skin metal wing are permitted, but since the lower sur...
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may be returned to refrigeration and used later without reheat treatment. 26 of 252 2/17/26, 13:31 Heat-treated rivets of the D or DD series that are not driven within the prescribed time after heat treatment, or which have been removed from refrigeration, must be heat-treated again before they are used. There is no sp...
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The minimum radius of bend, or as it is more commonly called, the minimum bend radius, is the sharpest bend that can be made in a piece of metal without critically weakening the part. 116. Threaded rivets (Rivnuts) are commonly used to A. join two or more pieces of sheet metal where shear strength is desired. B. attach...
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The advantages of a HI-LOK two-piece fastener include its light weight, high fatigue resistance, high strength, and its inability to be overtorqued. 123. What precaution, if any, should be taken to prevent corrosion inside a repaired metal honeycomb structure? A. Prime the repair with a corrosion inhibitor and seal fro...
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tightened to a firm fit. 31 of 252 2/17/26, 13:31 When bolts and self-locking nuts are used to hold transparent plastic enclosures in place, the nut should be tightened to a firm fit, then backed off one full turn. This installation procedure allows the plastic material to expand and contract without placing it under s...
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The strength of a well-designed and properly prepared wood splice joint is provided by the A. bearing surface of the wood fibers. C. reinforcement plates. The strength of a well-designed and properly prepared wood splice is provided completely by the glue. No other type of load-carrying fastener is used in a glued join...
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Moisture, mildew, chemicals, and acids have no effect on A. glass fabric. B. cotton fabric. C. polyester fabric. Glass cloth used as an aircraft structural material is not affected by moisture, mildew, chemicals, or acids. It is also fire resistant. 145. Cabin upholstery materials installed in current standard category...
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When a piece of sheet metal is bent, the curvature of the inside of the bend is referred to as the bend radius. 151. What type of bit should be used to drill holes in Plexiglas? A. A standard twist drill. B. A specially modified twist drill. C. A dulled twist drill. When holes are to be drilled completely through Plexi...
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Gussets are used to carry stresses from one member into another at the point the members join each other. 157. When conducting a tap test on a composite panel, which of the following sounds would indicate delamination? A. Sharp ringing. B. Dull thud. C. Sharp thud. Tap testing is a common technique used for the detecti...
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The determining factor(s) for the selection of the correct weight of textile fabric to be used in covering any type of aircraft is the A. maximum wing loading. B. speed of the aircraft. C. speed of the aircraft and the maximum wing loading. The weight of the fabric approved for use on an aircraft structure is determine...
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When the panel is heated to about 150°F, the noise caused by disbonding of the adhesive will be heard as a crackling sound. 40 of 252 2/17/26, 13:31 169. Compression failures in wood aircraft structures are characterized by buckling of the fibers that appear as streaks on the surface A. at right angles to the growth ri...
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If the joint separates with no wood fibers clinging to the glue, the glue has deteriorated. 175. Fabric rejuvenator is used to A. restore the condition of dope coatings. B. restore fabric strength and tautness to at least the minimum acceptable level. C. penetrate the fabric and restore fungicidal resistance. Rejuvenat...
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Which parts of a semi-monocoque fuselage prevent tension and compression from bending the fuselage? A. Ribs and formers. B. Longerons and stringers. C. Bulkheads and skin. 43 of 252 2/17/26, 13:31 In a semi-monocoque fuselage, the primary bending loads are taken by the longerons, which usually extend across several poi...
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Using a long strip of glass fiber and resin to attach a hinge to a large flat surface will cause the surface to warp, but if short strips of fiberglass are used to bond the fasteners to the panel, the warpage will be minimized. 190. The part of a replacement honeycomb core that must line up with the adjacent original i...
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The preferred way of making a permanent repair to a composite structure is to remove the damaged area and lay in new repair plies, observing the choice of materials, the overlap dimensions, ply orientation, and curing procedures. 197. When patching a plywood skin, abrupt changes in cross-sectional areas which will deve...
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The reinforced shell monocoque structure has the skin reinforced by a complete framework of structural members. 203. Where is information found concerning acceptable species substitutions for wood materials used in aircraft repair? A. AC 43.13-1. 48 of 252 2/17/26, 13:31 B. Aircraft Specifications or Type Certificate D...
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According to AC 43.13-1, fiberglass damage that goes completely through a laminate sandwich structure may be repaired by using either a stepped-joint or a scarfed-joint repair. Both types of repair are described in AC 43.13-1. 211. What reference tool is used to determine how the fiber is to be oriented for a particula...
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the behavior of the trailing edge when the surface is suspended from its hinge points. C. suspending the control surface from its leading edge in the stream line position and checking weight distribution. The static balance of a control surface can be checked by suspending the surface from its hinge points and noting t...
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Aircraft Specification or Type Certificate Data Sheet. B. Manufacturer's service bulletins. C. Aircraft service or maintenance manual. The precise information needed to perform a symmetry-alignment check for a particular aircraft is in the service or maintenance manual for that aircraft. 225. Improper rigging of the el...
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Where does the breakage of control cable wires occur most frequently? A. Breakage usually occurs where cables pass over pulleys and through fairleads. B. Breakage sites are unpredictable and usually occur randomly anywhere along the length of a cable. C. Breakage usually occurs where cables are swaged to turnbuckle and...
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bubble level and special fixtures described by the manufacturer. C. straightedge, tape measure, and carpenter's square. A bubble level and a special fixture may be used to determine the amount of twist that is put into a sheet-metal wing. 238. What nondestructive checking method is normally used to ensure that the corr...
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increasing the angle of incidence of the left wing, or decreasing the angle of incidence of the right wing, or both. B. increasing the dihedral angle of the left wing, or decreasing the dihedral angle of the right wing, or both. C. adjusting the dihedral angle of the left wing so that differential pressure between the ...
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Locating the center of lift behind the CG produces a nose-heavy tendency that is balanced by the downward aerodynamic tail load. When the nose pitches up, the aircraft slows down and the tail load decreases. Longitudinal stability causes the nose to drop back to the level flight attitude. If the nose pitches down, the ...
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An all-metal aircraft structure expands and contracts far more than steel control cables with changes in temperature. If the control cable tension is adjusted when the aircraft is warm, the tension will decrease when the aircraft and cables become cold. Most large aircraft have cable tension regulators to maintain a co...
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An aircraft with good (positive) static longitudinal stability automatically generates a restoring force anytime it pitches either nose up or nose down. If the amount of pitching increases, the aircraft has dynamic longitudinal instability. The aircraft in this question has poor longitudinal stability. 62 of 252 2/17/2...
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This includes the number of degrees of flap travel. 266. The purpose of wing slats is to A. reduce stalling speed. B. decrease drag. C. reduce lift. A wing slat allows an aircraft to fly at a higher angle of attack before it stalls. Allowing flight at a higher angle of attack reduces the stalling speed. 267. After repa...
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each aileron to have a greater up travel (from the streamlined position) than down travel. 65 of 252 2/17/26, 13:31 B. each aileron to have greater down travel (from the streamlined position) than up travel. C. the left aileron to move through a greater number of degrees (from full up to full down) than the right ailer...
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mechanic of an approved alternate method to perform a maintenance task other than specified in the aircraft maintenance manual. B. aircraft owners and operators of methods, techniques, and acceptable practices for inspection and alterations of aircraft. C. aircraft owners and other interested persons of unsafe conditio...
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A 100-hour inspection time may be extended for up to 10 hours, but these extended hours must be subtracted from the next inspection period. 283. Which statement about Airworthiness Directives (ADs) is true? A. ADs are information alert bulletins issued by the airframe, powerplant, or component manufacturer. B. Complian...
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To reach the nut, a 2-inch straight adapter must be used on an 18-inch torque wrench. How many foot-pounds will be indicated on the torque wrench when the required torque of the nut is reached? 69 of 252 2/17/26, 13:31 To solve this problem, use the formula: Tw = (Ta x L) / (L + A). (320 x 18) / (18 + 2) = 288 inch-pou...
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Replace the affected fusible plugs. C. Replace with new wheel assembly. Fusible plugs or thermal plugs must be inspected visually. These threaded plugs have a core that melts at a lower temperature than the outer part of the plug. This is to release air from the tire should the temperature rise to a dangerous level. A ...
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Brake deboosters are installed between the power brake control valve and the wheel cylinders of aircraft that are equipped with power brakes that use pressure supplied by the aircraft main hydraulic system. System pressure is too high for smooth brake application, so the debooster decreases the pressure and increases t...
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A steering damper is a hydraulically operated device that accomplishes the functions of steering and eliminating shimmying. The steering damper automatically reverts to damping when, for any reason, the flow of high-pressure fluid is removed from its inlet. 307. An antiskid system is designed to A. solely sense the dec...
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In a lockout debooster, when fluid is lost, the piston moves to the bottom of its stroke and the riser unseats the ball check valve, but the spring-loaded lockout valve prevents fluid entering the lower chamber until the reset handle is lifted. 312. Landing gear warning systems usually provide which of the following in...
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Aircraft landing gear that are retracted and lowered with an electric motor use a series-wound motor because of its high starting torque and a split-field motor to both raise and lower the gear. 319. A special bolt in a landing gear attachment requires a torque value of 440 inch- pounds. How many foot-pounds are requir...
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Overinflated tires may cause damage to the wheel flange on a hard landing. 325. The correct inflation pressure for an aircraft tire can be obtained from A. tire manufacturer's specifications. B. the aircraft service manual. 78 of 252 2/17/26, 13:31 C. the information stamped on the aircraft wheel. The aircraft service ...
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The centering cam ensures that the wheel is positioned so it will fit into the wheel well properly when it is retracted. 332. Why do most aircraft tire manufacturers recommend that the tubes in newly installed tires be first inflated, fully deflated, and then reinflated to the correct pressure? A. To allow the tube to ...
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When an airplane is slowed below approximately 20 mph, the antiskid system automatically activates to give the pilot full control of the brakes for maneuvering and parking. B. An antiskid system consists of two components; wheel speed sensors and control valves. 81 of 252 2/17/26, 13:31 When an airplane is slowed below...
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B. down and lock switch is open. C. antiskid valves are open. An aircraft with an antiskid system cannot land with the brakes applied even if the brake pedals are depressed. When the aircraft is airborne, the landing gear squat switch causes the antiskid control box to prevent fluid reaching the brakes. 345. What type ...
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nose gear extension at higher air speeds. B. reduce the possibility of hydroplaning. 84 of 252 2/17/26, 13:31 C. deflect water away from the fuselage. The nosewheel tires on aircraft with turbine engines mounted on the aft fuselage are often equipped with chines, or deflectors, molded into the outer sidewalls. The chin...
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reduce the pressure to the brake and increase the volume of fluid flow. Debooster cylinders are used in brake systems to reduce the pressure applied to the brake and to increase the volume of fluid flowing into the brake. Brake deboosters are used only with brakes that have power brake control valves and get their flui...
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Fluid level. If a shock strut bottoms during landing, the fluid is probably low. Transfer of the fluid from one chamber to another cushions the impact of landing, whereas the air pressure cushions the shocks produced when the aircraft is taxiing. 364. Internal leakage in a brake master cylinder unit can cause A. fading...
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Which statement is true with respect to an aircraft equipped with hydraulically operated multiple-disc type brake assemblies? A. There are no minimum or maximum disc clearance checks required due to the use of self-compensating cylinder assemblies. B. Do not set parking brake when brakes are hot. C. No parking brake pr...
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releasing the air and seeing that the oil is to the level of the filler plug. The oil level in an oleo shock strut is checked by releasing the air from the strut and filling the strut with oil to the level of the filler plug. 377. The purpose of a sequence valve in a hydraulic retractable landing gear system is to A. p...
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What action, if any, should be taken when there is a difference of more than 5 pounds of air pressure in tires mounted as duals? A. Replace both tires. B. Correct the discrepancy and enter in the aircraft records. C. Replace the tire with the lowest pressure. If there is a difference of more than 5 psi pressure between...
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Which valve installed in a hydraulic system will have the highest pressure setting? A. Pressure regulator valve. B. Main relief valve. C. Thermal relief valve. 93 of 252 2/17/26, 13:31 A thermal relief valve would be adjusted to a higher pop-off pressure than any of the other valves in a hydraulic system. Thermal relie...
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If hydraulic fluid is released when the air valve core of the accumulator is depressed, it is evidence of A. excessive accumulator air pressure. B. a leaking check valve. C. a ruptured diaphragm or leaking seals. A ruptured diaphragm or leaking seal in an accumulator will allow hydraulic fluid to get into the air side ...
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The installation of a new metal hydraulic line should be made with A. a straight tube to withstand the shocks and vibration to which it will be subjected. B. a straight tube to permit proper alignment of the fitting and thereby reduce fluid loss through leakage. C. enough bends to allow the tube to expand and contract ...
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Even though a hydraulic accumulator has been charged with air, no system pressure will show on the main system gauge until fluid has been pumped into the fluid side of the accumulator. 409. Components containing phosphate ester-base hydraulic fluid may be cleaned with A. Stoddard solvent. C. Carbon tetrachloride. Syste...
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The crossflow valve permits fluid to flow from the up side of the piston to the down side and thus allows the gear to fall more easily and with an even motion. 99 of 252 2/17/26, 13:31 415. Teflon hose that has developed a permanent set from being exposed to high pressure or temperature should A. not be straightened or...
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All fluids are considered to be highly compressible. C. All fluids readily transmit pressure. All fluids, whether gases or liquids, transmit pressure in a fluid power system. A liquid is a noncompressible fluid and a gas, such as air, is a compressible fluid. 424. The main system pressure relief valve in a simple hydra...
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Operate a hydraulic unit slowly and note the pressure at which a rapid pressure drop begins as it goes toward zero. The air pressure charge in an accumulator may be determined by slowly operating some hydraulic unit, such as the power brakes, to bleed the pressure off of the system. Watch the system pressure gauge. The...
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When servicing aircraft hydraulic systems, be sure to use only the type of fluid specified in the aircraft manufacturer's maintenance manual or on the instruction plate attached to the reservoir or to the unit. 437. Characteristics of MIL-H-5606 hydraulic fluid are A. light purple color, phosphate ester base, fire resi...
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If two actuating cylinders which have the same cross-sectional area but different lengths of stroke are connected to the same source of hydraulic pressure, they will exert A. different amounts of force but will move at the same rate of speed. B. equal amounts of force but will move at different rates of speed. C. equal...
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If an engine-driven hydraulic pump of the correct capacity fails to maintain normal system pressure during the operation of a cowl flap actuating unit, the probable cause is A. mechanical interference to the movement of the cowl flap. B. a partial restriction in the inport of the selector valve. C. restriction in the p...
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The volume remains the same, but the pump output pressure drops to almost zero. The system pressure regulator traps the pressure in the system where it is held by the accumulator. 454. How can the proper hydraulic fluid to be used in an airplane be determined? A. By referring to the Pilot Operating Handbook. B. By cons...
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A moisture separator must be used in an aircraft pneumatic system that incorporates engine-driven compressors. The moisture separator separates the moisture from the compressed air before the air is allowed to expand in the system. If moisture were allowed to remain in the air, the temperature drop that occurs when the...
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It also stores power for limited operation of components when the pump is not operating. 467. The purpose of restrictors in hydraulic systems is to A. control the rate of movement of hydraulically operated mechanisms. B. allow the flow of fluid in one direction only. C. lower the operating pressure of selected componen...
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A hydraulic system referred to as a 'power pack' system will A. have an engine-driven pump for greater pressure. B. have all hydraulic power components located in one unit. C. have a pressurized reservoir. A hydraulic power pack is a small, self-contained hydraulic system that includes the reservoir, pump, selector val...
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One of the distinguishing characteristics of an open-center selector valve used in a hydraulic system is that A. fluid flows through the valve in the OFF position. B. fluid flows in three directions in the ON position. C. a limited amount of fluid flows in one direction and no fluid flows in the opposite direction. In ...
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Seals used with a mineral-base hydraulic fluid are identified by which color code? A. Green dash. B. Blue dot or stripe. C. Yellow dot or stripe. The material of which the seal is made, its age, and its hardness are all important when making the proper replacement. Mineral-base hydraulic fluid (MIL-H-5606) should use a...
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emergency pump at any time it is required. C. normal system power pump. The normal system power pump connects to the fluid outlet of the reservoir that is fed from the standpipe. If the power pump forces all of the fluid available to it overboard through a broken line, there will still be fluid in the reservoir that ca...
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Which of the following is the most commonly used seal to prevent internal and external leakage in both directions of a hydraulic unit? The most commonly used type of seal for preventing both internal and external leakage in a hydraulic system component is an O-ring seal. 119 of 252 2/17/26, 13:31 499. What type of valv...
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Air in the accumulator is kept out of the fluid portion of the hydraulic system by the two chambers of the accumulator being separated by a diaphragm, a bladder, or a movable piston. 504. If it is necessary to adjust several pressure regulating valves in a hydraulic system, what particular sequence, if any, should be f...
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On a volume basis, the storage capacity of oxygen in candles is about three times that of compressed gas. The generators of a chemical oxygen system are inert below 400°F, even under severe impact. The distribution and regulating system is self-contained. It consists of a stainless steel cylinder attached to manifolded...
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What component in a vapor-cycle cooling system would most likely be at fault if a system would not take a freon charge? A. Expansion valve. 123 of 252 2/17/26, 13:31 If a vapor-cycle air cooling system does not take a charge of refrigerant, the most likely component to be at fault is the thermal expansion valve. It tak...
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outflow valve to close slower. B. outflow valve to close faster. C. cabin compressor speed to decrease. If the cabin rate of climb is too great, the outflow valve should be made to close faster to prevent the cabin altitude from changing too rapidly. 522. What is the main cause of contamination in a gaseous oxygen syst...
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Hot compressor bleed air loses some of its heat energy as it flows through a primary heat exchanger. This slightly cooled air then flows into the air-cycle machine where it is compressed and its temperature and pressure are both increased. This heated air then passes through a secondary heat exchanger, where it gives u...
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Outside air passing over the condenser coils removed some of the heat and caused the refrigerant to condense into a high-pressure liquid. 532. The purpose of a subcooler in a vapor-cycle cooling system is to A. augment the cooling capacity during periods of peak demand. B. aid in quick cooling a hot aircraft interior. ...
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In a freon vapor-cycle cooling system, where is cooling air obtained for the condenser? A. Turbine engine compressor. B. Ambient air. 129 of 252 2/17/26, 13:31 C. Pressurized cabin air. The air that passes through the condenser coils is ambient, or outside, air and it removes the heat from the heated and pressurized re...
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The outside air temperature must be high enough for all of the liquid to change into a vapor before it reaches the compressor. 545. The basic air-cycle cooling system consists of A. a source of compressed air, heat exchangers, and a turbine. B. heaters, coolers, and compressors. C. ram air source, compressors, and engi...
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The operation of the cabin pressure regulator is determined by the cabin air pressure or, more accurately, by the cabin altitude. 551. A small amount of water in a vapor cycle cooling system can freeze A. in the receiver-dryer and stop the entire system operation. B. in the expansion valve and stop the entire system op...
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In the condenser, ambient air blowing over the coils absorbs heat from the refrigerant and changes back into a liquid, ready to begin its trip through the system again to pick up more heat from the cabin. 556. What does a steady stream of bubbles indicate when servicing a vapor cycle air conditioning system? A. The sys...
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To make human flight possible in the hostile environment of the upper atmosphere. Pressurizing aircraft cabins creates the proper environment for prevention of hypoxia. Pressurizing aircraft cabins permits operation at high altitudes. 562. The air-cycle cooling system produces cold air by A. extracting heat energy acro...
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Its pressure is dropped to that of a low-pressure liquid as it passes through the thermal expansion valve. From the thermal expansion valve, the low-pressure liquid enters the evaporator coils. As it passes through the evaporator, it absorbs heat from the cabin air flowing over the coils and changes into a low-pressure...
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138 of 252 2/17/26, 13:31 A cycle is one complete series of events or operations that recur regularly. An aircraft pressurization cycle consists of a takeoff, scheduled pressurization, scheduled decrease in pressure, and depressurization. 573. What controls the amount of oxygen delivered to a mask in a continuous-flow ...
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Chemical oxygen generator systems are used as emergency backup for pressurized aircraft because of their lack of complexity, efficient use of space and weight, and the small amount of maintenance they require. 579. The purpose of the airflow metering aneroid assembly found in oxygen diluter demand regulators is to A. r...
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141 of 252 2/17/26, 13:31 The dump valve in a pressurized aircraft relieves all positive pressure from the cabin when the aircraft is on the ground. 585. High-pressure cylinders containing oxygen for aviation use can be identified by their A. green color and the words BREATHING OXYGEN stenciled in 1-inch white letters....
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In a high-pressure oxygen system, if the pressure reducer fails, what prevents high-pressure oxygen from entering the system downstream? A. Check valve. B. Pressure relief valve. C. Manifold control valve. If the pressure reducer valve in an installed, high-pressure oxygen system should fail, a pressure relief valve wi...
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When installing an instrument in an aircraft, who is responsible for making sure it is properly marked? A. The aircraft owner or pilot. B. The mechanic installing the instrument. C. The manufacturer of the instrument. When an instrument is installed in an aircraft instrument panel, it is the responsibility of the techn...
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Which of the following operating mechanisms would be found in a hydraulic pressure gauge? A. Bourdon tube. B. Pressure diaphragm. C. Evacuated bellows. Most hydraulic pressure gauges use a Bourdon tube-type mechanism. 146 of 252 2/17/26, 13:31 605. When selecting hardware for attaching bonding connections to an aircraf...
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position and pressure. A Bourdon tube instrument is a pressure-measuring instrument. It can be used to measure temperature by connecting it to a temperature bulb containing a volatile liquid such as methyl chloride. The bulb and the Bourdon tube are connected with a small-diameter copper tube and are sealed as a unit. ...
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Cabin altimeter and cabin rate-of-change indicator. B. Vertical speed indicator and altimeter. C. Vertical speed indicator, altimeter, and airspeed indicator. The vertical speed indicator, the altimeter and the airspeed indicator are connected to the aircraft pitot-static system. 149 of 252 2/17/26, 13:31 618. Instrume...
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altimeter after pressure has been applied to the static system to cause a prescribed equivalent altitude to be indicated. C. altimeter after suction has been applied to the static system to cause a prescribed equivalent altitude to be indicated. Instrument static system leakage can be detected by observing the rate of ...
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In aviation, there is also a commonly used pressure known as standard pressure. Standard pressure refers to an established or standard value that has been created for atmospheric pressure. This standard pressure value is 29.92 inches of mercury ("Hg), 1,013.2 hectopascal (hPa), or 14.7 psi. 632. A typical takeoff warni...
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