Airframe Q&A FAA

by KimberlyJho-ann

Airframe questionnaire that I want in audio version!

1. (8001) Laminated wood spars may be substituted for solid rectangular wood spars

*b. if the same quality wood is used in both.

2. (8002) The strength of a well-designed and properly prepared wood splice joint is provided by the *b. glue.

3. (8003) Where is information found concerning acceptable species substitutions for wood materials used in aircraft repair? *a. AC 43.13-1B.

4. (8004) In cases of elongated boltholes in a wood spar or cracks in the vicinity of boltholes,

*c. a new section of spar should be spliced in or the spar replaced entirely.

5. (8005) A faint line running across the grain of a wood spar generally indicates

*a. compression failure.

6. (8006) Which statement about wood decay is correct?

*c. Decay is not acceptable in any form or amount.

7. (8007) Which of the following conditions will determine acceptance of wood with mineral streaks?

*a. Careful inspection fails to reveal any decay.

8. (8008) The I-beam wooden spar is routed to

*c. reduce weight.

9. (8009) Pin knot clusters are permitted in wood aircraft structure provided

*a. they produce a small effect on grain direction.

10. (8010) The cantilever wing uses

*b. no external bracing.

11. (8011) Laminated wood is sometimes used in the construction of highly stressed aircraft components. This wood can be identified by its

*a. parallel grain construction.

12. (8012) When patching a plywood skin, abrupt changes in cross-sectional areas which will develop dangerous stress concentration should be avoided by using

*a. circular or elliptical patches.

13. (8013) Glue deterioration in wood aircraft structure is indicated

*a. when a joint has separated and the glue surface shows only the imprint of the wood with no wood fibers clinging to the glue.

.

14. (8014) Compression failures in wood aircraft structures are characterized by buckling of the fibers that appear as streaks on the surface

*c. at right angles to the grain.

15. (8015) When and how is finishing tape applied on a fabric-covered aircraft?

*c. Doped on after the first or second coat of dope.

16. (8016) 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

. *c. speed of the aircraft and the maximum wing loading.

17. (8017) How many fabric thicknesses will be found in a French-fell seam?

*c. Four.

18. (8018) Finishing tape (surface tape) is used for what purpose?

*b. To provide additional wear resistance over the edges of fabric forming structures.

19. (8019) Moisture, mildew, chemicals, and acids have no effect on

*a. glass fabric.

20. (8020) The best method of repair for a fabric-covered surface which has an L-shaped tear, each leg of which is approximately 14 inches long, is to

*c. sew with a baseball stitch from the center of the tear out toward the extremity of each leg and then dope on a patch.

21. (8021) The strength classification of fabrics used in aircraft covering is based on

*c. tensile strength.

22. (8022) Fabric rejuvenator is used to

*a. restore the condition of dope coatings.

23. (8023) (1) Machine-sewn seams in aircraft covering

*b. only No. 1 is true.

24. (8024) 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

*b. 70 percent of the original strength for intermediate fabric.

25. (8025) When dope-proofing the parts of the aircraft structure that come in contact with doped fabric, which of the following provide an acceptable protective coating?

1. Aluminum foil.

2. Resin impregnated cloth tape.

3. Any one-part type metal primer.

4. Cellulose tape.

*c. 1 and 4.

26. (8026) If registration numbers are to be applied to an aircraft with a letter height of 12 inches, what is the minimum space required for the registration mark N1683C?

Note:

2/3 x height = character width.

1/6 x height = width for 1.

1/4 x 2/3 height = spacing.

1/6 x height = stroke or line width.

*a. 52 inches.

27. (8027) If masking tape is applied to an aircraft such as for trim spraying, and is left on for several days and/or exposed to heat, it is likely that the tape will *c. cure to the finish and be very difficult to remove.

28. (8028) What is used to slow the drying time of some finishes and to prevent blush?

*b. Retarder.

29. (8029) Which type of coating typically includes phosphoric acid as one of its components at the time of application?

*a. Wash primer.

30. (8030) Which properly applied finish topcoat is the most durable and chemical resistant?

*c. Polyurethane.

31. (8031) Aluminum-pigment in dope is used primarily to *c. reflect ultraviolet from the fabric.

32. (8032) A correct use for acetone is to

*b. remove grease from fabric.

33. (8033) Which of the following is a hazard associated with sanding on fabric covered surfaces during the finishing process? *b. Static electricity buildup.

34. (8034) What is likely to occur if unhydrated wash primer is applied to unpainted aluminum and then about 30 to 40 minutes later a finish topcoat, when the humidity is low?

*a. Corrosion.

35. (8035) Fungicidal dopes are used in aircraft finishing as the *b. first coat to prevent fabric rotting and are applied thin enough to saturate the fabric.

36. (8036) Before applying a protective coating to any unpainted clean aluminum, you should

*c. avoid touching the surface with bare hands.

37. (8037) What is likely to occur if hydrated wash primer is applied to unpainted aluminum and then about 30 to 40 minutes later a finish topcoat, when the humidity is low?

*b. A glossy, blush-free finish.

38. (8038) What is the usual cause of runs and sags in aircraft finishes?

*a. Too much material applied in one coat.

39. (8039) Which defect in aircraft finishes may be caused by adverse humidity, drafts, or sudden changes in temperature?

*b. Blushing.

40. (8040) Which statement is true regarding paint system compatibility? *c. Old wash primer coats may be overcoated directly with epoxy finishes.

41. (8041) A well-designed rivet joint will subject the rivets to *b. shear loads.

42. (8042) A main difference between Lockbolt/Huckbolt tension and shear fasteners (other than their application) is in the. *a. number of locking collar grooves.

43. (8043) Alloy 2117 rivets are heat treated

*a. by the manufacturer and do not require heat treatment before being driven.

44. (8044) The general rule for finding the proper rivet diameter is *c. three times the thickness of the thickest sheet.

45. (8045) The shop head of a rivet should be

. *a. one and one-half times the diameter of the rivet shank.

46. (8046) One of the main advantages of Hi-Lok type fasteners over earlier generations is that

*c. they can be installed with ordinary hand tools.

47. (8047) The markings on the head of a Dzus fastener identify the

. *a. body diameter, type of head, and length of the fastener.

48. (8048) The Dzus turnlock fastener consists of a stud, grommet, and receptacle. The stud length is measured in

~ The stud length of a Dzus fastener is measured in 1/100-inch increments.

The stud length of a Dzus fastener is measured in 1/100-inch increments. *a. hundredths of an inch.

49. (8049) The Dzus turnlock fastener consists of a stud, grommet, and receptacle. The stud diameter is measured in

*c. sixteenths of an inch.

50. (8050) Threaded rivets (Rivnuts) are commonly used to *b. attach parts or components with screws to sheet metal.

51. (8051) The installation of Cherrymax and Olympic-Lok rivets is accomplished by utilizing

. *b. a pulling tool.

52. (8052) Hole filling fasteners (for example, MS20470 rivets) should not be used in composite structures primarily because of the

*a. possibility of causing delamination.

53. (8053) Metal fasteners used with carbon/graphite composite structures

*b. must be constructed of material such as titanium or corrosion resistant steel.

54. (8054) Sandwich panels made of metal honeycomb construction are used on modern aircraft because this type of construction

*a. has a high strength to weight ratio.

55. (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,

*b. only No. 1 is true.

56. (8056) Which of these methods may be used to inspect fiberglass/honeycomb structures for entrapped water?

1. Acoustic emission monitoring.

2. X-ray.

3. Backlighting.

*c. 2 and 3.

57. (8057) When balsa wood is used to replace a damaged honeycomb core, the plug should be cut so that *c. the grain is perpendicular to the skin.

58. (8058) When repairing puncture-type damage of a metal faced laminated honeycomb panel, the edges of the doubler should be tapered to *b. 100 times the thickness of the metal.

59. (8059) One of the best ways to assure that a properly prepared batch of matrix resin has been achieved is to

*b. have mixed enough for a test sample.

60. (8060) How does acoustic emission testing detect defects in composite materials? *a. By picking up the 'noise' of any deterioration that may be present.

61. (8061) 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 from the atmosphere.

62. (8062) One method of inspecting a laminated fiberglass structure that has been subjected to damage is to

*a. strip the damaged area of all paint and shine a strong light through the structure.

63. (8063) When inspecting a composite panel using the ring test/tapping method, a dull thud may indicate *b. separation of the laminates.

64. (8064) How many of the following are benefits of using microballoons when making repairs to laminated honeycomb panels?

1. Greater concentrations of resin in edges and corners.

2. Improved strength to weight ratio.

3. Less density

4. Lower stress concentrations

*a. 2, 3, and 4.

65. (8065) The length of time that a catalyzed resin will remain in a workable state is called the *a. pot life.

66. (8066) A category of plastic material that is capable of softening or flowing when reheated is described as a *a. thermoplastic.

67. (8067) The classification for high tensile strength fiberglass used in aircraft structures is *b. S-glass.

68. (8068) Which is an identifying characteristic of acrylic plastics?

. *a. Zinc chloride will have no effect.

69. (8069) Superficial scars, scratches, surface abrasion, or rain erosion on fiberglass laminates can generally be repaired by applying

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

70. (8070) The classification for fiberglass reinforcement material that has high resistivity and is the most common is *a. E-glass.

71. (8071) A potted compound repair on honeycomb can usually be made on damages less than

*c. 1 inch in diameter.

72. (8072) Composite fabric material is considered to be the strongest in what direction? *b. Warp.

73. (8073) What reference tool is used to determine how the fiber is to be oriented for a particular ply of fabric?

*c. Warp clock (or compass).

74. (8074) The strength and stiffness of a properly constructed composite buildup depends primarily on *b. the orientation of the plies to the load direction.

75. (8075) Which fiber to resin (percent) ratio for advanced composite wet lay-ups is generally considered the best for strength? *c. 60:40.

76. (8076) What is the material layer used within the vacuum bag pressure system to absorb excess resin during curing called?

*a. Bleeder.

77. (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. *b. 1 and 4.

78. (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

*b. use short strips of fiberglass in the bonded repair.

79. (8079) When making repairs to fiberglass, cleaning of the area to be repaired is essential for a good bond. The final cleaning should be made using *a. MEK (methyl ethyl ketone).

80. (8080) When necessary, what type of cutting fluid is usually acceptable for machining composite laminates?

*c. Water only.

81. (8081) Fiberglass laminate damage not exceeding the first layer or ply can be repaired by *a. filling with a putty consisting of a compatible resin and clean, short glass fibers.

82. (8082) Fiberglass damage that extends completely through a laminated sandwich structure *a. may be repaired.

83. (8083) Fiberglass laminate damage that extends completely through one facing and into the core

*b. requires the replacement of the damaged core and facing.

84. (8084) Repairing advanced composites using materials and techniques traditionally used for fiberglass repairs is likely to result in *c. an unairworthy repair.

85. (8085) The preferred way to make permanent repairs on composites is by

*c. laminating on new repair plies.

86. (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.

*a. 2 and 3.

87. (8087) The part of a replacement honeycomb core that must line up with the adjacent original is the

*b. ribbon direction.

88. (8088) Which of the following are generally characteristic 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. *a. 1 and 2.

89. (8089) Which of the following are generally characteristic 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. *b. 2, 3, and 4.

90. (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

*c. crazing.

91. (8091) When installing transparent plastic enclosures which are retained by bolts extending through the plastic material and self-locking nuts, the nuts should be

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

92. (8092) If a new safety belt is to be installed in an aircraft, the belt must conform to the strength requirements in which document? *c. TSO C22.

93. (8093) Which is considered good practice concerning the installation of acrylic plastics?

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

94. (8094) The coefficient of expansion of most plastic enclosure materials is *a. greater than both steel and aluminum.

95. (8095) If no scratches are visible after transparent plastic enclosure materials have been cleaned, their surfaces should be *c. covered with a thin coat of wax.

96. (8096) Cabin upholstery materials installed in current standard category airplanes must *b. be at least flame resistant.

97. (8097) What is the most common method of cementing transparent plastics?

*b. Soak method.

98. (8098) What type of bit should be used to drill holes in Plexiglas? *b. A specially modified twist drill.

99. (8099) What is the purpose of a gusset or gusset plate used in the construction and repair of aircraft structures? *c. To join and reinforce intersecting structural members.

100. (8100) Select the alternative which best describes the function of the flute section of a twist drill. *c. Forms the cutting edges of the drill point.

101. (8101) How many MS20470 AD-4-6 rivets will be required to attach a 10 x 5 inch plate, using a single row of rivets, minimum edge distance, and 4D spacing?

. *a. 56

102. (8102) Longitudinal (fore and aft) structural members of a semi-monocoque fuselage are called

*b. longerons and stringers.

103. (8103) Shallow scratches in sheet metal may be repaired by *a. burnishing.

104. (8104) What should be the included angle of a twist drill for soft metals? *b. 90¡.

105. (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 *b. lower speed with more pressure applied to the drill.

106. (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

*c. 13/16 inch.

107. (8107) Which statement is true regarding the inspection of

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

108. (8108) What is the minimum edge distance for aircraft rivets?

*a. Two times the diameter of the rivet shank.

109. (8109) When drilling stainless steel, the drill used should have an included angle of

*c. 140¡ and turn at a low speed.

110. (8110) What is the minimum spacing for a single row of aircraft rivets?

*c. Three times the diameter of the rivet shank.

111. (8111) (Refer to Figure 1.) Which of the rivets shown will accurately fit the conical depression made by a 100¡ countersink?

*a. 1

112. (8112) Which is correct concerning the use of a file?

*a. Apply pressure on the forward stroke, only, except when filing very soft metals such as lead or aluminum.

113. (8113) What is one of the determining factors which permits machine countersinking when flush riveting?

*c. Thickness of the material is greater than the thickness of the rivet head.

114. (8114) When repairing a small hole on a metal stressed skin, the major consideration in the design of the patch should be

*a. the shear strength of the riveted joint.

115. (8115) Which procedure is correct when using a reamer to finish a drilled hole to the correct size?

*b. Turn the reamer only in the cutting direction.

116. (8116) Repairs or splices involving stringers on the lower surface of stressed skin metal wings are usually

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

117. (8117) When straightening members made of 2024-T4, you should

*a. straighten cold and reinforce.

118. (8118) Clad aluminum alloys are used in aircraft because they

*b. are less subject to corrosion than uncoated aluminum alloys.

119. (8119) Which statement is true regarding a cantilever wing?

*b. No external bracing is needed.

120. (8120) Aircraft structural units, such as spars, engine supports, etc., which have been built up from sheet metal, are normally

*a. repairable, using approved methods.

121. (8121) A factor which determines the minimum space between rivets is the

*b. diameter of the rivets being used.

122. (8122) What should be the included angle of a twist drill for hard metal?

*a. 118¡.

123. (8123) Parts fabricated from Alclad 2024-T3 aluminum sheet stock must have all

*c. scratches, kinks, tool marks, nicks, etc., must be held to a minimum.

124. (8124) The monocoque fuselage relies largely on the strength of

*b. skin or covering.

125. (8125) Which part(s) of a semi-monocoque fuselage prevent(s) tension and compression from bending the fuselage?

*b. Longerons and stringers.

126. (8126) Rivet gauge, or transverse pitch is the distance between the

*a. centers of rivets in adjacent rows.

127. (8127) Rivet pitch is the distance between the

*b. centers of adjacent rivets in the same row.

128. (8128) (Refer to Figure 2.) Select the preferred drawing *c. 1

129. (8129) What is indicated by a black 'smoky' residue streaming back from some of the rivets on an aircraft?

*c. Fretting corrosion is occurring between the rivets and the skin.

130. (8130) The identifying marks on the heads of aluminum alloy rivets indicate the

*c. specific alloy used in the manufacture of the rivets.

131. (8131) When an MS20470D rivet is installed, its full shear strength is obtained

*a. only after a period of age hardening.

132. (8132) Which of the following need not be considered when determining minimum rivet spacing?

.

*b. Rivet length.

133. (8133) What is the purpose of refrigerating 2017 and 2024 aluminum alloy rivets after heat treatment?

*c. To retard age hardening.

134. (8134) Under certain conditions, type A rivets are not used because of their

*a. low strength characteristics.

135. (8135) A rivet set used to drive MS20470 rivets should

*b. have a slightly greater radius than the rivet head.

136. (8136) Heat-treated rivets in the D and DD series that are not driven within the prescribed time after heat treatment or removal from refrigeration

*a. must be reheat treated before use.

137. (8137) The dimensions of an MS20430AD-4-8 rivet are

*b. 1/8 inch in diameter and 1/2 inch long.

138. (8138) The primary alloying agent of 2024-T3 is indicated by the number

~ The primary alloying agent in 2024-T3 aluminum alloy is copper, which is identified by the first digit 2.

The primary alloying agent in 2024-T3 aluminum alloy is copper, which is identified by the first digit 2.

*a. 2

139. (8139) Which part of the 2017-T36 aluminum alloy designation indicates the primary alloying agent used in its manufacture?

*a. 2

140. (8140) A sheet metal repair is to be made using two pieces of 0.040-inch aluminum riveted together. All rivet holes are drilled for 3/32-inch rivets. The length of the rivets to be used will be

*b. 1/4 inch.

141. (8141) Most rivets used in aircraft construction have

*a. dimples.

142. (8142) MS20426AD-6-5 indicates a countersunk rivet which has

*c. an overall length of 5/16 inch.

143. (8143) Which rivet may be used as received without further treatment?

.

*b. 2117-T3.

144. (8144) (Refer to Figure 3.) Which is the grip length of the flush rivet?

*c. 3

145. (8145) Which rivets should be selected to join two sheets of .032-inch aluminum?

*b. MS20470AD-4-4.

146. (8146) A sheet metal repair is to be made using two pieces of 0.0625-inch aluminum riveted together. All rivet holes are drilled for 1/8-inch rivets. The length of the rivets to be used will be

*c. 5/16 inch.

147. (8147) Mild steel rivets are used for riveting

*c. steel parts.

148. (8148) A DD rivet is heat treated before use to

*c. soften to facilitate riveting.

149. (8149) When riveting dissimilar metals together, what precautions must be taken to prevent an electrolytic action?

*b. Place a protective separator between areas of potential electrical difference.

150. (8150) The length of a rivet to be used to join a sheet of .032-inch and .064-inch aluminum alloy should be equal to

*b. one and one-half times the rivet diameter plus .096 inch.

151. (8151) What is generally the best procedure to use when removing a solid shank rivet?

*b. Drill to the base of the manufactured rivet head with a drill one size smaller than the rivet shank and remove the rivet with a punch.

152. (8152) Joggles in removed rivet shanks would indicate partial

*c. shear failure.

153. (8153) What type loads cause the most rivet failures?

*a. Shear.

154. (8154) Which rivet is used for riveting magnesium alloy structures?

*b. 5056 aluminum.

155. (8155) Which rivet is used for riveting nickel-steel alloys?

.

*c. Monel.

156. (8156) The length of rivet to be chosen when making a structural repair that involves the joining of 0.032-

inch and 0.064-inch aluminum sheet, drilled with a No. 30 drill, is

*b. 5/16 inch.

157. (8157) (Refer to Figure 4.) The length of flat A is

*a. 3.750 inches.

.

158. (8158) (Refer to Figure 4.) The amount of material required to make the 90¡ bend is

*a. 0.3436 inch.

159. (8159) (Refer to Figure 5.) What is the length of flat A?

*a. 3.7 inches.

.

160. (8160) (Refer to Figure 5.) What is the flat layout dimension?

*b. 6.8 inches.

161. (8161) If a streamline cover plate is to be hand formed using a form block, a piece of dead soft aluminum should first be placed over the hollow portion of the mold and securely fastened in place. The bumping operation should be

*b. started by tapping the aluminum lightly around the edges and gradually working down into the center.

162. (8162) A piece of flat stock that is to be bent to a closed angle of 15¡ must be bent through an angle of

*a. 165¡.

163. (8163) When a piece of aluminum alloy is to be bent using a minimum radius for the type and thickness of material,

.

*b. the layout should be made so that the bend will be 90¡ to the grain of the sheet.

164. (8164) The flat layout or blank length of a piece of metal from which a simple L-shaped bracket 3 inches by 1 inch is to be bent depends upon the radius of the desired bend. The bracket which will require the greatest amount of material is one which has a bend radius of

*a. 1/8 inch.

165. (8165) If it is necessary to compute a bend allowance problem and bend allowance tables are not available, the neutral axis of the bend can be

*b. found by adding approximately one-half of the stock thickness to the bend radius.

166. (8166) Unless otherwise specified, the radius of a bend is the

*a. inside radius of the metal being formed.

167. (8167) The sharpest bend that can be placed in a piece of metal without critically weakening the part is called the

*b. minimum radius of bend.

168. (8168) The most important factors needed to make a flat pattern layout are *b. radius, thickness, and degree of bend.

.

169. (8169) A piece of sheet metal is bent to a certain radius. The curvature of the bend is referred to as the

*c. bend radius.

170. (8170) You can distinguish between aluminum and aluminum alloy by

*c. testing with a 10 percent solution of caustic soda.

171. (8171) The purpose of a joggle is to *a. allow clearance for a sheet or an extrusion.

172. (8172) When bending metal, the material on the outside of the curve stretches while the material on the

inside of the curve compresses. That part of the material which is not affected by either stress is the

*c. neutral line.

173. (8173) (Refer to Figure 6.) Determine the dimensions of A, B, and C in the flat layout.

Setback = .252

Bend allowance = .345

*b. A = .748, B = 1.496, C = 1.248.

174. (8174) (Refer to Figure 6.) What is dimension D?

Setback = .252

Bend allowance = .345

*b. 4.182.

.

175. (8175) The sight line on a sheet metal flat layout to be bent in a cornice or box brake is measured and marked

*c. one radius from the bend tangent line that is placed under the brake.

176. (8176) (Refer to Figure 7.) What is dimension F?

Setback at D = .095

Setback at E = .068

Bend allowance at D = .150

Bend allowance at E = .112 *b. 5.936.

177. (8177) On a sheet metal fitting layout with a single bend, allow for stretching by

*c. subtracting the setback from both legs.

178. (8178) The aluminum alloys used in aircraft construction are usually hardened by which method?

*c. Heat treatment.

179. (8179) In Gas Tungsten Arc (GTA) welding, a stream of inert gas is used to

*a. prevent the formation of oxides in the puddle.

180. (8180) Which statement best describes magnesium welding?

*c. Filler rod should be the same composition as base metal.

181. (8181) Which statement is true in regard to welding heat-treated magnesium? *a. The welded section does not have the strength of the original metal.

182. (8182) The oxyacetylene flame for silver soldering should be *b. neutral.

183. (8183) Why is it necessary to use flux in all silver soldering operations?

*a. To chemically clean the base metal of oxide film.

184. (8184) Engine mount members should preferably be repaired by using a

*b. larger diameter tube with fishmouth and rosette welds.

185. (8185) What method of repair is recommended for a steel tube longeron dented at a cluster?

*c. Welded patch plate.

186. (8186) Welding over brazed or soldered joints is *a. not permitted.

187. (8187) Which statement concerning soldering is correct?

*a. Joints in electric wire to be soldered should be

mechanically secure prior to soldering.

188. (8188) A resurfaced soldering iron cannot be used effectively until after the working face has been *c. tinned.

189. (8189) Which of the following can normally be welded without adversely affecting strength?

1. Aircraft bolts.

2. SAE 4130 chrome/molybdenum tubing.

3. Spring steel struts.

4. Most heat-treated steel/nickel alloy components. *c. 2

190. (8190) In selecting a torch tip size to use in welding, the size of the tip opening determines the *a. amount of heat applied to the work.

191. (8191) Why should a carburizing flame be avoided when welding steel? *b. It hardens the surface.

192. (8192) The most important consideration(s) when selecting welding rod is *b. material compatibility.

193. (8193) The oxyacetylene flame used for aluminum welding should *a. be neutral and soft.

194. (8194) A very thin and pointed tip on a soldering copper is undesirable because it will *c. cool too rapidly.

195. (8195) Filing or grinding a weld bead is considered to be *b. a way to bring about strength reduction in joint.

196. (8196) Acetylene at a line pressure above 15 PSI is *a. dangerously unstable.

197. (8197) Cylinders used to transport and store acetylene

*c. contain acetone.

198. (8198) A welding torch backfire may be caused by *a. a loose tip.

199. (8199) Which statement concerning a welding process is true? *a. The inert-arc welding process uses an inert gas to protect the weld zone from the atmosphere.

200. (8200) Where should the flux be applied when oxyacetylene welding aluminum? *b. Painted on the surface to be welded and applied to the welding rod.

201. (8201) What purpose does flux serve in welding aluminum? *b. Minimizes or prevents oxidation.

202. (8202) Why are aluminum plates 1/4 inch or more thick usually preheated before welding? *a. Reduces internal stresses and assures more complete penetration.

203. (8203) How should a welding torch flame be adjusted to weld stainless steel? *a. Slightly carburizing.

204. (8204) Oxides form very rapidly when alloys or metals are hot. It is important, therefore, when welding aluminum to use a *c. flux.

205. (8205) In gas welding, the amount of heat applied to the material being welded is controlled by the *b. size of the tip opening.

206. (8206.1) Oxygen and acetylene cylinders are made of *b. steel.

207. (8207) When a butt welded joint is visually inspected for penetration,

*b. the penetration should be 100 percent of the thickness of the base metal.

208. (8208) Annealing of aluminum *c. removes stresses caused by forming.

209. (8209) Edge notching is generally recommended in butt welding above a certain thickness of aluminum because it *c. aids in getting full penetration of the metal and prevents local distortion.

210. (8210) If too much acetylene is used in the welding of stainless steel, *b. the metal will absorb carbon and lose its resistance to corrosion.

211. (8211) The shielding gases generally used in the Gas Tungsten Arc (GTA) welding of aluminum consist of

*c. helium or argon, or a mixture of helium and argon.

212. (8206.2) High pressure cylinders used to transport and store acetylene must *c. contain acetone.

213. (8212) The auxiliary (tail) rotor of a helicopter permits the pilot to compensate for and/or accomplish which of the following? *c. Torque and directional control.

214. (8213) The vertical flight of a helicopter is controlled by *a. collective pitch changes.

215. (8214) A reduction in anti-torque thrust will cause the *b. tail to pivot in the direction of torque rotation around the main rotor axis.

216. (8215) In rotorcraft external-loading, the ideal location of the cargo release is where the line of action passes *c. through the center of gravity at all times.

217. (8216) The acute angle formed by the chord line of a wing and the relative wind is known as the *c. angle of attack.

218. (8217) A helicopter in forward flight, cruise configuration, changes direction by *c. tilting the main rotor disk in the desired direction.

219. (8218) The purpose in checking main rotor blade tracking is to determine the *a. relative position of the blades during rotation.

220. (8219) In a hovering helicopter equipped with a tail rotor, directional control is maintained by *c. varying the pitch of the tail rotor blades.

221. (8220) If a single-rotor helicopter is in forward horizontal flight, the angle of attack of the advancing blade is

*c. less than the retreating blade.

222. (8221) Main rotor blades that do not cone by the same amount during rotation are said to be out of *c. track.

223. (8222) One purpose of the freewheeling unit required between the engine and the helicopter transmission is to *a. automatically disengage the rotor from the engine in case of an engine failure.

224. (8223) Which statement is correct concerning torque effect on helicopters? *c. Torque direction is the opposite of rotor blade rotation.

225. (8224) What is the purpose of the free-wheeling unit in a helicopter drive system? *a. It disconnects the rotor whenever the engine stops or slows below the equivalent of rotor RPM.

226. (8225) Movement about the longitudinal axis (roll) in a helicopter is effected by movement of the *b. cyclic pitch control.

227. (8226) Movement about the lateral axis (pitch) in a helicopter is effected by movement of the *b. cyclic pitch control.

228. (8227) Wing dihedral, a rigging consideration on most airplanes of conventional design, contributes most to stability of the airplane about its *a. longitudinal axis.

229. (8228) Other than the manufacturer maintenance manual what other document could be used to determine the primary flight control surface deflection for an imported aircraft that is reassembled after shipment? *a. Aircraft type certificate data sheet.

230. (8229) If a pilot reports that an airplane flies left wing heavy, this condition may be corrected by *a. increasing the angle of incidence of the left wing, or decreasing the angle of incidence of the right wing, or both.

231. (8230) If the vertical fin of a single-engine, propeller-driven airplane is rigged properly, it will generally be parallel to *b. the vertical axis but not the longitudinal axis.

232. (8231) An airplane which has good longitudinal stability should have a minimum tendency to *b. pitch.

233. (8232) As the angle of attack of an airfoil increases, the center of pressure will *c. move toward the leading edge.

234. (8233) The angle of incidence is that acute angle formed by *b. a line parallel to the wing chord and a line parallel to the longitudinal axis of the aircraft.

235. (8234) An airplane's center of lift is usually located aft of its center of gravity

*b. so that the airplane will have a nose-heavy tendency.

236. (8235) An airplane is controlled directionally about its vertical axis by the *a. rudder.

237. (8236) The elevators of a conventional airplane are used to provide rotation about the *b. lateral axis.

238. (8237) Washing-in the left wing of a monoplane, for purposes of rigging corrections after flight test, will have what effect on the lift and drag of that wing? *b. Both drag and lift will increase due to increased angle of attack.

239. (8238) What type of flap system increases the wing area and changes the wing camber? *a. Fowler flaps.

240. (8239) If the right wing of a monoplane is improperly rigged to a greater angle of incidence than designated in the manufacturer's specifications, it will cause the *a. airplane to be off balance both laterally and directionally.

241. (8240) The chord of a wing is measured from *c. leading edge to trailing edge.

242. (8241) When the lift of an airfoil increases, the drag will *b. also increase.

243. (8242) What physical factors are involved in the aspect ratio of airplane wings? *b. Span and chord.

244. (8243) Improper rigging of the elevator trim tab

system will affect the balance of the airplane about its *a. lateral axis.

245. (8244) An airplane that has a tendency to gradually increase a pitching moment that has been set into motion has *a. poor longitudinal stability.

246. (8245) The purpose of wing slats is to *a. reduce stalling speed.

247. (8246) The angle of incidence of an airplane at rest *c. does not change when in flight.

248. (8247) Buffeting is the intermittent application of forces to a part of an airplane. It is caused by

~ Buffeting is an intermittent application of forces on *b. an unsteady flow from turbulence.

249. (8248) Movement of an airplane along its lateral axis (roll) is also movement *c. around or about the longitudinal axis controlled by the ailerons.

250. (8249) The primary purpose of stall strips is to *b. stall the inboard portion of the wings first.

251. (8250) Rigging and alignment checks should not be undertaken in the open; however, if this cannot be avoided, the aircraft should be positioned *c. with the nose into the wind.

252. (8251) The correct dihedral angle can be determined by *c. using a dihedral board and bubble level along the front spar of each wing.

253. (8252) The dihedral angle of a wing may be measured by placing a straightedge and level protractor on the

*a. front spar.

254. (8253) Where would you find precise information to

perform a symmetry alignment check for a particular aircraft? *c. Aircraft service or maintenance manual.

255. (8254) Where is the buttock line or buttline of an aircraft? *c. A width measurement left or right of, and parallel to, the vertical centerline.

256. (8255) Where is fuselage station No. 137 located? *b. 137 inches aft of the zero or fixed reference line.

257. (8256) Proper wing twist in a sheet metal constructed wing can usually be checked by utilizing a *b. bubble level and special fixtures described by the manufacturer.

258. (8257) The vast majority of aircraft control cables are terminated with swaged terminals, that must be *c. checked with a go-no-go gauge before and after, to show compliance with the manufacturer's requirements after the swaging operation.

259. (8258) What nondestructive checking method is normally used to ensure that the correct amount of swaging has taken place when installing swaged-type terminals on aircraft control cable? *c. Use a terminal gauge to check the diameter of the swaged portion of the terminal.

260. (8259) When inspecting a control cable turnbuckle for proper installation, determine that *c. the safety wire ends are wrapped a minimum of four turns around the terminal end shanks.

261. (8260) If all instructions issued by the swaging tool manufacturer are followed when swaging a cable terminal, the resultant swaged terminal strength should be *a. the full rated strength of the cable.

262. (8261) Which is an acceptable safety device for a castle nut when installed on secondary structures? *c. Cotter pin.

263. (8262) When used in close proximity to magnetic compasses, cotter pins are made of what material? *a. Corrosion resisting steel.

264. (8263) When a fiber or nylon insert-type, self-locking nut can be threaded on a bolt or stud through the insert with only the fingers, it should be *b. rejected.

265. (8264) The purpose of the vertical fin is to provide *a. directional stability.

266. (8265) How are changes in direction of a control cable accomplished? *a. Pulleys.

267. (8266) What is the smallest size cable that may be used in aircraft primary control systems? *c. 1/8 inch.

268. (8267) After repairing or re-covering a rudder, the surface should be rebalanced *c. to manufacturer's specifications.

269. (8268) Placing a piece of cloth around a stainless steel control cable and running it back and forth over the length of the cable is generally a satisfactory method of *b. inspecting for broken wires.

270. (8269) The cable-operated control system of an all-metal aircraft, not incorporating a temperature compensating device, has been rigged to the correct tension in a heated hangar. If the aircraft is operated in very cold weather, the cable tension will *a. decrease when the aircraft structure and cables become cold.

271. (8270) Very often, repairs to a control surface require static rebalancing of the control surface. Generally, flight control balance condition may be determined by

*b. the behavior of the trailing edge when the surface is suspended from its hinge points.

272. (8271) Excessive wear on both of the sides of a control cable pulley groove is evidence of *a. pulley misalignment.

273. (8272) Fairleads should never deflect the alignment of a cable more than *c. 3¡.

274. (8273) Where does the breakage of control cable wires occur most frequently? *a. Breakage usually occurs where cables pass over pulleys and through fairleads.

275. (8274) With which system is differential control associated? *b. Aileron.

276. (8275) Which statement concerning the 100-hour inspection of an airplane equipped with a push-pull tube-type control system is true? *c. The threaded rod ends should be checked for the amount of thread engagement by means of the inspection hole provided.

277. (8276) If control cables are adjusted properly and the control surfaces tend to vibrate, the probable cause is *a. worn attachment fittings.

278. (8277) Aircraft flight control trim systems must be designed and installed so that the *a. pilot can determine the relative position of the trim tab from the cockpit.

279. (8278) Stability about the axis which runs parallel to the line of flight is referred to as *b. lateral stability.

280. (8279) The purpose of spring tabs or servo tabs is to

*a. assist the pilot in moving the control surfaces.

281. (8280) If the control stick of an aircraft with properly rigged flight controls is moved rearward and to the left, the right aileron will move *c. down and the elevator will move up.

282. (8281) Movement of the cockpit control toward the nosedown position during a ground operational check of the elevator trim tab system will cause the trailing edge of the trim tab to move in which direction? *b. Upward regardless of elevator position.

283. (8282) If the control stick of an aircraft with properly rigged flight controls is moved forward and to the right, the left aileron will move *c. down and the elevator will move down.

284. (8283) If the travel of an airplane's controls is correct but the cables are rigged exceptionally tight, what probable effect will this have when flying the airplane? *b. The airplane will be heavy on the controls.

285. (8284) During inspection of the flight control system of an airplane equipped with differential-type aileron control, side-to-side movement of the control stick will cause *a. each aileron to have a greater up travel (from the streamlined position) than down travel.

286. (8285) A universal propeller protractor used to measure the degrees of aileron travel should be zeroed *a. with the aileron in the NEUTRAL position.

287. (8286) The universal propeller protractor can be used to measure *c. degrees of flap travel.

288. (8287) (Refer to Figure 8.) Identify the cable that

is used in primary control systems and in other places where operation over pulleys is frequent. *c. 3

289. (8288) A tension regulator in the flight control cable system of a large all-metal aircraft is used primarily to *c. retain a set tension.

290. (8289) (Refer to Figure 9.) When the outside air temperature is 80¡F, select the acceptable 3/16 cable tension range. *b. 117 pounds minimum, 143 pounds maximum.

291. (8290) Differential control on an aileron system means that *b. the up travel is more than the down travel.

292. (8291) Why is it generally necessary to jack an aircraft indoors for weighing? *b. So that air currents do not destabilize the scales.

293. (8292) Which should be accomplished before jacking an aircraft? *a. Install critical stress panels or plates.

294. (8293) Which statement about Airworthiness Directives (AD's) is true? *c. Compliance with an applicable AD is mandatory and must be recorded in the maintenance records.

295. (8294) When overhauling electrical equipment, all necessary information should be obtained from *b. maintenance instructions published by the aircraft and/or equipment manufacturer.

296. (8295) Which statement is correct regarding an aircraft that is found to be unairworthy after an annual inspection, due to an item requiring a major repair (assuming approved data is used to accomplish the repair)? *a. An appropriately rated mechanic may accomplish the repair, and an IA may approve the aircraft for return to service.

297. (8296) Radio equipment installations made in accordance with Supplemental Type Certificate data require approval for return to service *c. by the holder of an inspection authorization.

298. (8297) An aircraft may be flown beyond the 100-hour inspection requirement to reach a place where the inspection can be accomplished, provided it *a. does not exceed 10 flight hours.

299. (8298) Where would you find the recommended statement for recording the approval or disapproval for return to service of an aircraft after a 100-hour or annual inspection? *b. 14 CFR Part 43.

300. (8299) The maximum time a 100-hour inspection may be extended is *a. 10 hours.

301. (8300) Which statement is correct when an aircraft has not been approved for return to service after an annual inspection because of several items requiring minor repair? *b. An appropriately rated mechanic may repair the defects and approve the aircraft for return to service.

302. (8301) An aircraft that is due an annual inspection may be flown *a. if a special permit has been issued for the aircraft.

303. (8302) For an individual (not a repair station) to conduct a complete 100-hour inspection on an aircraft and approve it for return to service requires a mechanic certificate with *b. airframe and powerplant ratings.

304. (8303) Where would you find the operating conditions that make a 100-hour inspection mandatory? *a. 14 CFR Part 91.

305. (8304) Large airplanes and turbine-powered multiengine airplanes operated under Federal Aviation Regulation Part 91, General Operating and Flight Rules, must be inspected *a. in accordance with an inspection program authorized under Federal Aviation Regulation Part 91, Subpart E.

306. (8305) Exposure to and/or storage near which of the following is considered harmful to aircraft tires?

1. Low humidity.

2. Fuel.

3. Oil.

4. Ozone.

5. Helium.

6. Electrical equipment.

7. Hydraulic fluid.

8. Solvents. *c. 2, 3, 4, 6, 7, 8.

307. (8306) What would be the effect if the piston return spring broke in a brake master cylinder? *c. The brakes would drag.

308. (8307) In brake service work, the term 'bleeding brakes' is the process of *b. withdrawing fluid from the system for the purpose of removing air that has entered the system.

309. (8308) To prevent a very rapid extension of an oleo shock strut after initial compression resulting from landing impact, *a. various types of valves or orifices are used which restrict the reverse fluid flow.

310. (8309) A pilot reports the right brake on an aircraft is spongy when the brake pedal is depressed in a normal manner. The probable cause is

*b. air in the brake hydraulic system.

311. (8310) Aside from an external leak in the line, what will cause parking brakes to continually bleed off pressure?

*a. An internal leak in the master cylinder.

312. (8311) 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?

~ When a tube-type tire is mounted, the tube should be fully inflated, deflated, and then re-inflated. This procedure allows the tube to position itself inside the tire and to relieve all the stresses in the tube.

When a tube-type tire is mounted, the tube should be fully inflated, deflated, and then re-inflated. This procedure allows the tube to position itself inside the tire and to relieve all the stresses in the tube. *a. To allow the tube to position itself correctly inside the tire.

313. (8312) The metering pins in oleo shock struts serve to *b. retard the flow of oil as the struts are compressed.

314. (8313) After performing maintenance on an aircraft's landing gear system which may have affected the system's operation, it is usually necessary to *c. make an operational check with the aircraft on jacks.

315. (8314) Why do tire and wheel manufacturers often recommend that the tires on split rim wheels be deflated before removing the wheel from the axle? *b. As a safety precaution in case the bolts that hold the wheel halves together have been damaged or weakened.

316. (8315) The braking action of a Cleveland disk brake is accomplished by compressing a rotating brake disk between two opposite brake linings. How is equal pressure on both sides of the rotating disk assured? *b. By allowing the caliper to float to automatically equalize as pressure is applied to the rotor.

317. (8316) If it is determined that spongy brake action is not caused by air in the brake system, what is the next most likely cause?

*c. Deteriorated flexible hoses.

318. (8317) Many brake types can be adapted to operate mechanically or hydraulically. Which type is not adaptable to mechanical operation? *c. Expander-tube type.

319. (8318) A brake debooster valve is installed in systems where the high pressure of the hydraulic system (3000 psi) is used to operate brakes *a. that are designed to work with lower pressure.

320. (8319) A stripe or mark applied to a wheel rim and extending onto the sidewall of a tube-type tire is a *a. slippage mark.

321. (8320) When bleeding aircraft brakes, one of the indications that the air has been purged from the system is *c. firm brake pedals.

322. (8321) Overinflated aircraft tires may cause damage to the *c. wheel flange.

323. (8322) Debooster valves are used in brake systems primarily to *c. reduce the pressure and release the brakes rapidly.

324. (8323) The repair for an out-of-tolerance toe-in condition of main landing gear wheels determined not to be the result of bent or twisted components consists of *b. inserting, removing, or changing the location of washers or spacers at the center pivotal point of the scissor torque links.

325. (8324) On an air valve core stem, what indicates high-pressure type? *c. An embossed letter 'H.'

326. (8325) The primary purpose for balancing aircraft wheel assemblies is to *a. prevent heavy spots and reduce vibration.

327. (8326) Power boost brake systems are used on aircraft that have

*a. high landing speeds.

328. (8327) On all aircraft equipped with retractable landing gear, some means must be provided to *b. extend the landing gear if the normal operating mechanism fails.

329. (8328) An automatic damping action occurs at the steering damper if for any reason the flow of high-pressure fluid is removed from the *b. inlet of the steering damper.

330. (8329) What is the purpose of the torque links attached to the cylinder and piston of a landing gear oleo strut? *c. Maintain correct wheel alignment.

331. (8330) The removal, installation, and repair of landing gear tires by the holder of a private pilot certificate on an aircraft owned or operated is considered to be *c. preventive maintenance.

332. (8331) Aircraft brakes requiring a large volume of fluid to operate the brakes generally *c. use power brake control valves.

333. (8332) What is one effect a restricted compensator port of a master cylinder will have on a brake system? *c. The restriction will cause slow release of the brakes.

334. (8333) When an air/oil type of landing gear shock strut is used, the initial shock of landing is cushioned by *b. the fluid being forced through a metered opening.

335. (8334) Internal leakage in a brake master cylinder unit can cause *c. the pedal to slowly creep down while pedal pressure

is applied.

336. (8335) A sleeve, spacer, or bumper ring is incorporated in a landing gear oleo shock strut to *b. limit the extension stroke.

337. (8336) The purpose of a sequence valve in a hydraulic retractable landing gear system is to

*c. ensure operation of the landing gear and gear doors in the proper order.

338. (8337) The pressure source for power brakes is *a. the main hydraulic system.

339. (8338) Which statement is true with respect to an aircraft equipped with hydraulically operated multiple-disk type brake assemblies?

*b. Do not set parking brake when brakes are hot.

340. (8339) What type of valve is used in the brake actuating line to isolate the emergency brake system from the normal power brake control valve system? *c. A shuttle valve.

341. (8340) When servicing an air/oil shock strut with MIL-5606 the strut should be *a. collapsed and fluid added at the filler opening.

342. (8341) Instructions concerning the type of fluid and amount of air pressure to be put in a shock strut are found *c. in the aircraft manufacturer's service manual.

343. (8342) The purpose of a relief valve in a brake system is to *c. compensate for thermal expansion.

344. (8343) Aircraft tire pressure should be checked *b. at least once a week or more often.

345. (8344) If the extended longitudinal axis of the main landing gear wheel assemblies intersects aft of the

aircraft, the wheels can be termed as having *a. toe-out.

346. (8345) What is the purpose of a compensating port or valve in a brake master cylinder of an independent brake system? *a. Permits the fluid to flow toward or away from the reservoir as temperature changes.

347. (8346) If an aircraft shock strut (air/oil type) bottoms upon initial landing contact, but functions correctly during taxi, the most probable cause is *a. low fluid.

348. (8347) What is the function of a cam incorporated in a nose gear shock strut? *b. Straightens the nosewheel.

349. (8348) Extension of an oleo shock strut is measured to determine the *c. proper operating position of the strut.

350. (8349) Debooster cylinders are used in brake systems primarily to *c. reduce the pressure to the brake and increase the volume of fluid flow.

351. (8350) If a shock strut bottoms after it has been properly serviced, the *c. strut should be removed, disassembled, and inspected.

352. (8351) A high-speed aircraft tire with a sound cord body and bead may be recapped *c. an indefinite number of times.

353. (8352) If an airplane equipped with master cylinders and single-disk brakes has excessive brake pedal travel, but the brakes are hard and effective, the probable cause is *b. worn brake linings.

354. (8353) The correct inflation pressure for an aircraft tire can be obtained from

*b. the aircraft service manual.

355. (8354) What should be checked when a shock strut bottoms during a landing? *c. Fluid level.

356. (8355) How can it be determined that all air has been purged from a master cylinder brake system? *b. By noting whether the brake is firm or spongy.

357. (8356) The left brake is dragging excessively on an airplane on which no recent brake service work has been performed. The most probable cause is *a. foreign particles stuck in the master cylinder compensating port.

358. (8357) If a brake debooster is used in a hydraulic brake system, its position in the system will be *b. between the brake control valve and the brake actuating cylinder.

359. (8358) The hydraulic packing seals used in a landing gear shock strut are *c. used only with a specific type of fluid.

360. (8359) Lockout deboosters are primarily pressure reducing valves that *a. allow full debooster piston travel without fluid from the high pressure side entering the low pressure chamber.

361. (8360) When a properly operating fusible plug has allowed a tire to deflate, the tire should be *a. replaced.

362. (8361) Chines are used on some aircraft nose wheel tires to help *c. deflect water away from the fuselage.

363. (8362) The best safeguards against heat buildup in aircraft tires are *b. short ground rolls, slow taxi speeds, minimum braking, and proper tire inflation.

364. (8363) The fusible plugs installed in some aircraft wheels will *c. melt at a specified elevated temperature.

365. (8364) 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? *b. Correct the discrepancy and enter in the aircraft records.

366. (8365) How long should you wait after a flight before checking tire pressure? *a. At least 2 hours (3 hours in hot weather).

367. (8366) Excessive wear in the shoulder area of an aircraft tire is an indication of

*c. underinflation.

368. (8367) Excessive wear in the center of the tread of an aircraft tire is an indication of *c. overinflation.

369. (8368) When an empty shock strut is filled with fluid, care should be taken to extend and compress the strut completely at least two times to *c. ensure proper packing ring seating and removal of air bubbles.

370. (8369) In shock struts, chevron seals are used to *b. prevent oil from escaping.

371. (8370) On most aircraft, the oil level of an air and oil shock strut is checked by *c. releasing the air and seeing that the oil is to the level of the filler plug.

372. (8371) A pilot reports that the brake pedals have excessive travel. A probable cause is *b. lack of fluid in the brake system.

373. (8372) A landing gear position and warning system will provide a warning in the cockpit when the throttle is

*a. retarded and gear is not down and locked.

374. (8373) An electric motor used to raise and lower a landing gear would most likely be a

*c. split field series-wound motor.

375. (8374) When installing a chevron-type seal in an aircraft hydraulic cylinder, the open side of the seal should face

*c. the direction of fluid pressure.

376. (8375) Nose gear centering cams are used in many retractable landing gear systems. The primary purpose of the centering device is to

*c. center the nosewheel before it enters the wheel well.

377. (8376) What device in a hydraulic system with a constant-delivery pump allows circulation of the fluid when no demands are on the system?

*c. Pressure regulator.

378. (8377) A fully-charged hydraulic accumulator provides

*b. a source for additional hydraulic power when heavy demands are placed on the system.

379. (8378) A hydraulic system referred to as a 'power pack' system will

*b. have all hydraulic power components located in one unit.

380. (8379) A hydraulic hose identified as MIL-H-8794 will have a yellow stripe running the length of the hose. This stripe

*a. is used to ensure that the hose is installed without excessive twisting.

381. (8380) An O-ring intended for use in a hydraulic system using MIL-H-5606 (mineral base) fluid will be marked with

*a. a blue stripe or dot.

382. (8381) What condition would most likely cause excessive fluctuation of the pressure gauge when the hydraulic pump is operating?

*b. Inadequate supply of fluid.

383. (8382) A filter incorporating specially treated cellulose paper is identified as a

*c. micronic filter.

384. (8383) The purpose of an orifice check valve is to

*b. restrict flow in one direction and allow free flow in the other.

385. (8384) (Refer to Figure 10.) The trunnion nut on an aircraft landing gear requires a torque of 320 inch-pounds. 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?

*a. 24

386. (8385) A special bolt in a landing gear attachment requires a torque value of 440 inch-pounds. How many foot-pounds are required?

*c. 36.6.

387. (8386) To protect packing rings or seals from damage when it is necessary to install them over or inside threaded sections, the

*c. threaded section should be covered with a suitable sleeve.

388. (8387) To prevent external and internal leakage in aircraft hydraulic units, the most commonly used type of seal is the

*a. O-ring seal.

389. (8388) Which allows free fluid flow in one direction and no fluid flow in the other direction?

*a. Check valve.

390. (8389) Select the valve used in a hydraulic system that directs pressurized fluid to one end of an actuating cylinder and simultaneously directs return

fluid to the reservoir from the other end.

*c. Selector.

391. (8390) What function does the absolute pressure regulator perform in the pneumatic power system?

*c. Regulates the compressor inlet air to provide a stabilized source of air for the compressor.

392. (8391) (1) Relief valves are used in pneumatic systems as damage-preventing units.

(2) Check valves are used in both hydraulic and pneumatic systems.

Regarding the above statements,

*a. both No. 1 and No. 2 are true.

393. (8392) 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.

394. (8393) What type of packings should be used in hydraulic components to be installed in a system containing Skydrol?

*b. Packing materials made for ester base fluids.

395. (8394) Relief valves are used in pneumatic systems

*c. as damage-preventing units.

396. (8395) An aircraft pneumatic system, which incorporates an engine-driven multistage reciprocating compressor, also requires

*c. a moisture separator.

397. (8396) The removal of air from an aircraft hydraulic system is generally accomplished

*b. by operating the various hydraulic components through several cycles.

398. (8397) Pneumatic systems utilize

*b. relief valves.

399. (8398) The component in the hydraulic system that is used to direct the flow of fluid is the

*c. selector valve.

400. (8399) What type of selector valve is one of the most commonly used in hydraulic systems to provide for simultaneous flow of fluid into and out of a connected actuating unit?

*a. Four-port, closed-center valve.

401. (8400) What is the purpose of using backup rings with O-rings in hydraulic systems above 1,500 PSI?

*c. Prevent high pressure from extruding the seal between the moving and stationary part.

402. (8401) The purpose of the pressure regulator in a hydraulic system is to

*a. maintain system operating pressure within a predetermined range and to unload the pump.

403. (8402) A flexible sealing element subject to motion is a

*b. packing.

404. (8403) Which characteristics apply to aircraft hydraulic systems?

1. Minimum maintenance requirements.

2. Lightweight.

3. About 80 percent operating efficiency (20 percent loss due to fluid friction).

4. Simple to inspect.

*c. 1, 2, 4.

405. (8404) If a rigid tube is too short for the flare to reach its seat before tightening, pulling it into place by tightening

*b. may distort the flare.

406. (8405) The installation of a new metal hydraulic line should be made with

*c. enough bends to allow the tube to expand and contract with temperature changes and to absorb vibration.

407. (8406) Extrusion of an O-ring seal is prevented in a high-pressure system by the use of a

*c. backup ring on the side of the O-ring away from the pressure.

408. (8407) What is one advantage of piston-type hydraulic motors over electric motors?

*b. There is no fire hazard if the motor is stalled.

409. (8408) Generally, the first step in removing an accumulator from an aircraft is to

*a. relieve system pressure.

410. (8409) (Refer to Figure 11.) Which fitting is an AN flared-tube fitting?

*a. 1

411. (8410) (Refer to Figure 12.) Which illustration(s) show(s) the correct spiral for teflon backup rings?

*c. 1 and 3.

412. (8411) If a hydraulic brake system uses neoprene rubber packing materials, the correct hydraulic fluid to service the system is

*a. mineral base oil.

413. (8412) The internal resistance of a fluid which tends to prevent it from flowing is called

*b. viscosity.

414. (8413) What is the viscosity of hydraulic fluid?

*c. The internal resistance of a fluid which tends to prevent it from flowing.

415. (8414) Which is a characteristic of petroleum base hydraulic fluid?

*a. Flammable under normal conditions.

416. (8415) (1) When servicing aircraft hydraulic systems, use the type fluid specified in the aircraft manufacturer's maintenance manual or on the instruction plate affixed to the reservoir or unit.

(2) Hydraulic fluids for aircraft are dyed a specific color for each type of fluid.

Regarding the above statements,

*c. both No. 1 and No. 2 are true.

417. (8416) Petroleum base hydraulic fluid is which color?

*c. Red.

418. (8417) Which of the following is adversely affected by atmospheric humidity if left unprotected?

1. MIL-H-5606 hydraulic fluid.

2. Skydrol hydraulic fluid.

3. None of the above.

*c. 2

419. (8418) Which is a characteristic of synthetic base hydraulic fluid?

*b. High flash point.

420. (8419) Which statement about fluids is correct?

*c. All fluids readily transmit pressure.

421. (8420) Two types of hydraulic fluids currently being used in civil aircraft are

*a. mineral base, and phosphate ester base.

422. (8421) Which of the following lists only desirable properties of a good hydraulic fluid that has chemical stability?

*c. Low viscosity, high flash point, high fire point.

423. (8422) Characteristics of MIL-H-8446 (Skydrol 500 A & B) hydraulic fluid are

*b. light purple color, phosphate ester base, fire resistant, butyl rubber seals.

424. (8423) Where can information be obtained about the compatibility of fire-resistant hydraulic fluid with aircraft materials?

*a. Fluid manufacturer's technical bulletins.

425. (8424) Characteristics of MIL-H-5606 hydraulic fluid are

*c. red color, petroleum base, will burn, uses synthetic rubber seals.

426. (8425) Characteristics of MIL-H-7644 hydraulic fluid are

*c. blue color, vegetable base, will burn, natural rubber seals.

427. (8426) If an aircraft hydraulic system requires mineral base hydraulic fluid, but phosphate ester base hydraulic fluid is used, what will be the effect on the system?

*b. System will be contaminated, fluids will not blend, and the seals will fail.

428. (8427) What is used to flush a system normally serviced with MIL-H-5606 hydraulic fluid?

*b. Naphtha or varsol.

429. (8428) Components containing phosphate ester-base hydraulic fluid may be cleaned with

*a. Stoddard solvent.

430. (8429) How can the proper hydraulic fluid to be used in an airplane be determined?

*c. Consult the aircraft manufacturer's service manual.

431. (8430) Phosphate ester base hydraulic fluid is very

susceptible to contamination from

*b. water in the atmosphere.

432. (8431) (1) Materials which are Skydrol compatible or resistant include most common aircraft metals and polyurethane and epoxy paints.

(2) Skydrol hydraulic fluid is compatible with nylon and natural fibers.

Regarding the above statements,

*a. both No. 1 and No. 2 are true.

433. (8432) The hydraulic component that automatically directs fluid from either the normal source or an emergency source to an actuating cylinder is called a

*b. shuttle valve.

434. (8433) The primary purpose of a hydraulic actuating unit is to transform

*b. fluid pressure into useful work.

435. (8434) The primary function of the flap overload valve is to

*a. prevent the flaps from being lowered at airspeeds which would impose excessive structural loads.

436. (8435) A unit which transforms hydraulic pressure into linear motion is called

*a. an actuating cylinder.

437. (8436) If it is necessary to adjust several pressure regulating valves in a hydraulic system, what particular sequence, if any, should be followed?

*b. Units with the highest pressure settings are adjusted first.

438. (8437) If an aircraft's constant-pressure hydraulic system cycles more frequently than usual and no fluid leakage can be detected, the most probable cause is

*c. low accumulator air preload.

439. (8438) Unloading valves are used with many engine-driven hydraulic pumps to

*b. relieve the pump pressure.

440. (8439) What safety device is usually located between the driving unit and hydraulic pump drive shaft?

*c. Pump drive coupling shear section.

441. (8440) Which valve installed in a hydraulic system will have the highest pressure setting?

*c. Thermal relief valve.

442. (8441) Excluding lines, which components are required to make up a simple hydraulic system?

*b. Pump, reservoir, selector valve, and actuator.

443. (8442) Most variable displacement aircraft hydraulic pumps in use

*c. contain a built-in means of system pressure regulation.

444. (8443) In a gear-type hydraulic pump, a mechanical safety device incorporated to protect the pump from overload is the

*c. shear pin.

445. (8444) After installation of a rebuilt hydraulic hand pump, it is found that the handle cannot be moved in the pumping direction (pressure stroke). The most likely cause is an incorrectly installed

*c. hand pump outport check valve.

446. (8445) Pressure is a term used to indicate the force per unit area. Pressure is usually expressed in

*a. pounds per square inch.

447. (8446) 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

*c. equal amounts of force and will move at the same rate of speed.

448. (8447) Using a hand pump, pressure of 100 PSI has been built up in a hydraulic system. The hand pump

piston is 1 inch in diameter. A 1/2-inch line connects the hand pump to an actuating cylinder 2 inches in diameter. What is the pressure in the line between the hand pump and the actuator?

*a. 100 PSI.

449. (8448) Heat exchanger cooling units are required in some aircraft hydraulic systems because of

*b. high pressures and high rates of fluid flow.

450. (8449) Which is true regarding the ground check of a flap operating mechanism which has just been installed?

*b. If the time required to operate the mechanism decreases with successive operations, it indicates the air is being worked out of the system.

451. (8450) A hydraulic system operational check during ground runup of an aircraft indicates that the wing flaps cannot be lowered using the main hydraulic system, but can be lowered by using the emergency hand pump. Which is the most likely cause?

*c. The fluid level in the reservoir is low.

452. (8451) Many hydraulic reservoirs contain a small quantity of fluid which is not available to the main system pump. This fluid is retained to

*b. supply fluid to the auxiliary pump.

453. (8452) The unit which causes one hydraulic operation to follow another in a definite order is called a

*b. sequence valve.

454. (8453) The purpose of a hydraulic pressure regulator is to

*c. relieve the pump of its load when no actuating units

are being operated.

455. (8454) Severe kickback of the emergency hydraulic hand pump handle during the normal intake stroke will indicate which of the following?

*c. The hand pump outlet check valve is sticking open.

456. (8455) What type of valve in an aircraft hydraulic system permits fluid to flow freely in one direction, but restricts the rate at which fluid is allowed to flow in the other direction?

*c. Orifice check valve.

457. (8456) The main system pressure relief valve in a simple hydraulic system equipped with a power control valve should be adjusted

*a. with the power control valve held in the CLOSED position.

458. (8457) A hydraulic accumulator is charged with an air preload of 1,000 PSI. When a hydraulic system pressure of 3,000 PSI is developed, the pressure on the air side of the accumulator will be

*b. 3,000 PSI.

459. (8458) How is the air in a hydraulic accumulator prevented from entering the fluid system?

*b. By physically separating the air chamber from the oil chamber with a flexible or movable separator.

460. (8459) After a hydraulic accumulator has been installed and air chamber charged, the main system hydraulic pressure gauge will not show a hydraulic pressure reading until

*c. the fluid side of the accumulator has been charged.

461. (8460) Which must be done before adjusting the relief valve of a main hydraulic system incorporating a pressure regulator?

*a. Eliminate the action of the unloading valve.

462. (8461.1) Which seals are used with petroleum base hydraulic fluids?

*c. Buna-N.

463. (8462) The air that is expended and no longer needed when an actuating unit is operated in a pneumatic system is

*a. exhausted or dumped, usually overboard.

464. (8463) Some hydraulic systems incorporate a device which is designed to remain open to allow a normal fluid flow in the line, but closed if the fluid flow increases above an established rate. This device is generally referred to as a

*a. hydraulic fuse.

465. (8464) When hydraulic system pressure control and relief units fail to function properly, how are most systems protected against overpressure?

*a. A shear section on the main hydraulic pump drive shaft.

466. (8465) A worn hydraulic pump shaft seal can normally be detected by

*a. hydraulic fluid flowing from the pump drain line.

467. (8466) 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

*c. restriction in the pump outlet.

468. (8467) Before removing the filler cap of a pressurized hydraulic reservoir, in order to service the system, you must

*c. relieve the air pressure.

469. (8468) What happens to the output of a constant-displacement hydraulic pump when the hydraulic system pressure regulator diverts the fluid from the system to the reservoir?

*b. The output pressure reduces, but the volume remains the same.

470. (8469) Hydraulic system accumulators serve which of the following functions?

1. Dampen pressure surges.

2. Supplement the system pump when demand is beyond the pump's capacity.

3. Store power for limited operation of components if the pump is not operating.

4. Ensure a continuous supply of fluid to the pump.

*c. 1, 2, 3.

471. (8470) Chattering of the hydraulic pump during operation is an indication

*c. that air is entering the pump.

472. (8471) Quick-disconnect couplings in hydraulic systems provide a means of

*c. quickly connecting and disconnecting hydraulic lines without loss of fluid or entrance of air into the system.

473. (8472) Which seal/material is used with phosphate ester base hydraulic fluids?

*b. Butyl rubber.

474. (8473) A hydraulic pump is a constant-displacement type if it

*c. delivers a uniform rate of fluid flow.

475. (8474) A hydraulic motor converts fluid pressure to

*b. rotary motion.

476. (8475) A crossflow valve which is designed to bypass fluid from one side of an actuating cylinder to the other side, under certain conditions, may be found in some aircraft installed in the

*c. landing gear system.

477. (8476) Hydraulic fluid filtering elements constructed of porous paper are normally

*b. discarded at regular intervals and replaced with new filtering elements.

478. (8477) A pilot reports that when the hydraulic pump

is running, the pressure is normal. However, when the pump is stopped, no hydraulic pressure is available. This is an indication of a

*c. leaking accumulator air valve.

479. (8478) If fluid is added to a reservoir in a constant pressure hydraulic system while the system is pressurized, what will result?

*b. The fluid level will increase when system pressure is reduced.

480. (8479) In a hydraulic system that has a reservoir pressurized with turbine-engine compressor bleed air, which unit reduces the air pressure between the engine and reservoir?

*c. Air pressure regulator.

481. (8480) What is the main purpose of a pressurized reservoir in a hydraulic system?

*b. Prevent hydraulic pump cavitation.

482. (8481) One of the main advantages of skydrol is its

*a. wide operating temperature.

483. (8482) Hydraulic fluid reservoirs are sometimes designed with a standpipe in one of the outlet ports in order to assure emergency supply of fluid. The outlet port with the standpipe in it furnishes fluid to the

*c. normal system power pump.

484. (8483) An emergency supply of fluid is often retained in the main hydraulic system reservoir by the use of a standpipe. The supply line is connected to the

*a. inlet of the main hydraulic system.

485. (8484) To check the air charge in a hydraulic accumulator,

*a. reduce all hydraulic pressure, then observe the reading on the accumulator air gauge.

486. (8485) How would the air pressure charge in the accumulator be determined if the engine is inoperative, but the system still has hydraulic pressure?

*c. Operate a hydraulic unit slowly and note the

pressure at which a rapid pressure drop begins as it goes toward zero.

487. (8486) How many of these seals are used with petroleum base hydraulic fluids?

*b. Neoprene, Buna-N.

488. (8487) Hydraulic system thermal relief valves are set to open at a

*b. higher pressure than the system relief valve.

489. (8488) Chatter in a hydraulic system is caused by

*c. air in the system.

490. (8489) If hydraulic fluid is released when the air valve core of the accumulator is depressed, it is evidence of

*c. a ruptured diaphragm or leaking seals.

491. (8490) Although dents in the heel of a bend are not permissible, they are acceptable in the remainder of a hydraulic tube providing they are less than what percent of the tube diameter?

*c. 20

492. (8491) If the hydraulic system pressure is normal while the engine-driven pump is running, but there is no pressure after the engine has been shut off, it indicates

*b. no air pressure in the accumulator.

493. (8492) The purpose of restrictors in hydraulic systems is to

*a. control the rate of movement of hydraulically operated mechanisms.

494. (8493) A common cause of slow actuation of hydraulic components is

*c. internal leakage in the actuating unit.

495. (8494) A loud hammering noise in a hydraulic system having an accumulator usually indicates

*c. too low or no preload in the accumulator.

496. (8495) Teflon hose that has developed a permanent set from being exposed to high pressure or temperature should

*a. not be straightened or bent further.

497. (8496) In a typical high-pressure pneumatic system, if the moisture separator does not vent accumulated water when the compressor shuts down, a likely cause is a

*c. malfunctioning solenoid dump valve.

498. (8461.2) Seals used with a mineral base hydraulic fluid are identified by which color code?

*b. Blue dot or stripe.

499. (8497) Which section of a turbine engine provides high pressure bleed air to an air cycle machine for pressurization and air-conditioning?

*a. Low or high pressure compressor.

500. (8498) At which component in an air-cycle cooling system does air undergo a pressure and temperature drop?

*a. Expansion turbine.

501. (8499) In a freon vapor-cycle cooling system, where is cooling air obtained for the condenser?

*b. Ambient air.

502. (8500) What is ventilating air used for on a combustion heater?

*b. Carries heat to the places where needed.

503. (8501) Turbine engine air used for air-conditioning and pressurization is generally called

*c. bleed air.

504. (8502) In the combustion heater, combustion air

system, what prevents too much air from entering the heaters as air pressure increases?

*a. Either a combustion air relief valve or a differential pressure regulator.

505. (8503) The cabin pressure of an aircraft in flight is maintained at the selected altitude by

*c. controlling the rate at which air leaves the cabin.

506. (8504) What controls the operation of the cabin pressure regulator?

*a. Cabin altitude.

507. (8505) The basic air-cycle cooling system consists of

*a. a source of compressed air, heat exchangers, and a turbine.

508. (8506) The purpose of the dump valve in a pressurized aircraft is to relieve

*a. all positive pressure from the cabin.

509. (8507) What component might possibly be damaged if liquid refrigerant is introduced into the low side of a vapor-cycle cooling system when the pressure is too high or the outside air temperature is too low?

*a. Compressor.

510. (8508) How can it be determined that a vapor-cycle cooling system is charged with the proper amount of freon?

*a. Air bubbles in the sight glass disappear.

511. (8509) When charging a vapor-cycle cooling system after evacuation, the low-pressure gauge fails to come out of a vacuum. What is indicated?

*a. Blockage in the system.

512. (8510) 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.

513. (8511) Frost or ice buildup on a vapor-cycle cooling system evaporator would most likely be caused by

*c. inadequate airflow through the evaporator.

514. (8512) What test is used to determine the serviceability of an oxygen cylinder?

*c. Pressure test with water.

515. (8513) How often should standard weight high-pressure oxygen cylinders be hydrostatically tested?

*a. Every 5 years.

516. (8514) To be eligible for recharging, a DOT 3HT oxygen cylinder must have been hydrostatically tested every three years and be retired from service after

*a. 24 years or 4,380 filling cycles.

517. (8515) What type of oxygen system uses the rebreather bag-type mask?

*b. Continuous flow.

518. (8516) The altitude controller maintains cabin altitude by modulation of the

*c. outflow valve.

519. (8517) Hot compressor bleed air operates the conditioned air system on some turbine aircraft, cold air supplied by the

*c. ram air cycle cooling unit.

520. (8518) For use in pressurized aircraft, which is generally the least complicated and requires the least maintenance?

*a. Chemical oxygen generator systems.

521. (8519) The main cause of contamination in gaseous oxygen systems is

*a. moisture.

522. (8520) Where does the last stage of cooling in an

air-cycle air-conditioning system occur?

*c. Expansion turbine.

523. (8521) The point at which freon flowing through a vapor-cycle cooling system gives up heat and changes from a gas to a liquid is the

*a. condenser.

524. (8522) The point at which freon flowing through a vapor-cycle cooling system absorbs heat and changes from a liquid to a gas is the

*b. evaporator.

525. (8523) How is the cabin pressure of a pressurized aircraft usually controlled?

*b. By an automatic outflow valve that dumps all the pressure in excess of the amount for which it is set.

526. (8524) Which is considered a good practice concerning the inspection of heating and exhaust systems of aircraft utilizing a jacket around the engine exhaust as a heat source?

*a. Supplement physical inspections with periodic operational carbon monoxide detection tests.

527. (8525) On some cabin pressurization systems, pressurization on the ground is restricted by the

*a. main landing gear operated switch.

528. (8526) The cabin pressure control setting has a direct influence upon the

*a. outflow valve opening.

529. (8527) The function of the evaporator in a freon cooling system is to

*b. lower the temperature of the cabin air.

530. (8528) What is the purpose of a mixing valve in a compressor bleed air air-conditioning system?

*a. Control the supply of hot, cool, and cold air.

531. (8529) What component of a pressurization system prevents the cabin altitude from becoming higher than airplane altitude?

*b. Negative pressure relief valve.

532. (8530) If the liquid level gauge in a vapor-cycle cooling system indicates a low freon charge, the system should

*b. be operated for a period of time to reach a stable condition and then the freon level rechecked.

533. (8531) If the cabin rate of climb is too great, the control should be adjusted to cause the

*b. outflow valve to close faster.

534. (8532) The position of the thermostatic expansion valve in a vapor-cycle cooling system is determined by temperature and pressure of the

*c. freon in the outlet of the evaporator.

535. (8533) The function of the condenser in a freon cooling system is to

*a. transfer heat from the freon gas to ambient air.

536. (8534) The function of an expansion valve in a freon cooling system is to act as a metering device and to

*c. reduce the pressure of the liquid freon.

537. (8535) Which prevents a sudden loss of pressurization in the event that there is a loss of the pressurization source?

*c. Delivery air duct check valve.

538. (8536) When servicing an air-conditioning system that has lost all of its freon, it is necessary to

*b. check oil and add as necessary, evacuate the system, and add freon.

539. (8537) The primary function of the cabin pressurization system outflow valve is to

*b. maintain the desired cabin pressure.

540. (8538) One purpose of a jet pump in a pressurization and air-conditioning system is to

*b. provide for augmentation of airflow in some areas of the aircraft.

541. (8539) After cleaning or replacing the filtering element in a combustion heater fuel system, the system should be pressurized and

*a. all connections checked for leaks.

542. (8540) The operation of an aircraft combustion heater is usually controlled by a thermostat circuit which

*a. alternately turns the fuel on and off, a process known as cycling.

543. (8541) The air-cycle cooling system produces cold air by

*c. extracting heat energy across an expansion turbine.

544. (8542) (Refer to Figure 13.) Determine what unit is located immediately downstream of the expansion valve in a freon refrigeration system.

*c. Evaporator coils.

545. (8543) When checking a freon system, a steady stream of bubbles in the sight gauge indicates the charge is

*c. low.

546. (8544) An aircraft pressurization cycle is normally considered to be

*a. one complete series of events or operations that recur regularly.

547. (8545) Which best describes cabin differential pressure?

*b. Difference between the ambient and internal air pressure.

548. (8546) Composite oxygen bottles that conform to

DOT-E-8162 have a service life of

*c. 15 years or 10,000 filling cycles whichever occurs first.

549. (8547) The cabin pressurization modes of operation are

*b. differential, unpressurized, and isobaric.

550. (8548) (1) Usually bleed air from a gas-turbine engine compressor can be safely used for cabin pressurization.

(2) Independent cabin condition air machines (air cycle machine) can be powered by bleed air from an aircraft turbine engine compressor.

Regarding the above statements,

*c. both No. 1 and No. 2 are true.

551. (8549) A pressurization controller uses

*b. barometric pressure, cabin altitude, and cabin rate of change.

552. (8550) What unit in a vapor-cycle cooling system serves as a reservoir for the refrigerant?

*a. Receiver-dryer.

553. (8551) What is the condition of the refrigerant as it enters the condenser of a vapor-cycle cooling system?

*c. High-pressure vapor.

554. (8552) What is the condition of the refrigerant as it enters the evaporator of a vapor-cycle cooling system?

*b. Low-pressure liquid.

555. (8553) The evacuation of a vapor-cycle cooling system removes any water that may be present by

*c. lowering the boiling point of the water and drawing out the vapor.

556. (8554) What is the condition of the refrigerant as it leaves the evaporator of a vapor-cycle cooling

system?

*b. Low-pressure vapor.

557. (8555) What is the condition of the refrigerant as it leaves the condenser of a vapor-cycle cooling system?

*b. High-pressure liquid.

558. (8556) In what position should the bottle be placed when adding liquid freon to a vapor-cycle cooling system?

*c. Vertical with the outlet at the bottom.

559. (8557) When purging a freon air-conditioning system, it is important to release the charge at a slow rate. What is the reason for the slow-rate discharge?

*b. Prevent excessive loss of refrigerant oil.

560. (8558) When a vapor-cycle cooling system is not in operation, what is an indication that the system is leaking freon?

*a. Oil seepage.

561. (8559) In an operating vapor-cycle cooling system, if the two lines connected to the expansion valve are essentially the same temperature, what does this indicate?

*b. The expansion valve is not metering freon properly.

562. (8560) The purpose of a subcooler in a vapor-cycle cooling system is to

*c. cool the freon to prevent premature vaporization.

563. (8561) (1) A small amount of water in a vapor-cycle cooling system can freeze in the receiver-dryer and stop the entire system operation.

(2) Water in a vapor-cycle cooling system will react with refrigerant to form hydrochloric acid which is highly corrosive to the metal in the system.

Regarding the above statements,

*b. only No. 2 is true.

564. (8562) When Refrigerant-12 is passed over an open flame, it

*c. changes to phosgene gas.

565. (8563) What type of oil is suitable for use in vapor-cycle cooling system?

*b. Special high grade refrigeration oil.

566. (8564) When an aircraft's oxygen system has developed a leak, the lines and fittings should be

*c. bubble tested with a special soap solution manufactured specifically for this purpose.

567. (8565) If oxygen bottle pressure is allowed to drop below a specified minimum, it may cause

*c. moisture to collect in the bottle.

568. (8566) What controls the amount of oxygen delivered to a mask in a continuous-flow oxygen system?

*a. Calibrated orifice.

569. (8567) In the diluter demand oxygen regulator, when does the demand valve operate?

*c. When the user breathes.

570. (8568) The primary difference between aviation breathing oxygen and other types of commercially available compressed oxygen is that

*b. aviation breathing oxygen has had all the water vapor removed.

571. (8569) What is used in some oxygen systems to change high cylinder pressure to low system pressure?

*a. Pressure reducer valve.

572. (8570) In a high-pressure oxygen system, if the pressure reducer fails, what prevents high-pressure oxygen from entering the system downstream?

*b. Pressure relief valve.

573. (8571) High-pressure cylinders containing oxygen for aviation use can be identified by their

*c. green color and the words 'AVIATOR'S BREATHING OXYGEN' stenciled in 1-inch white letters.

574. (8572) (Refer to Figure 14.) One hour after an oxygen system was charged for a leakage check, the oxygen pressure gauge read 460 PSI at 63¡F; 6 hours later the temperature was 51¡F. (A 5 PSI change is the maximum allowable in a 6-hour period.) What pressure gauge readings would be acceptable to remain within the allowable limits?

*a. 445 to 450 PSI.

575. (8573) An aircraft oxygen bottle may be considered airworthy if it has been hydrostatically tested and identified

*a. with the test date, DOT number and serial number stamped on the cylinder near the neck.

576. (8574) In a gaseous oxygen system, which of the following are vented to blow out plugs in the fuselage skin?

*a. Pressure relief valves.

577. (8575) The purpose of pressurizing aircraft cabins is to

(1) create the proper environment for prevention of hypoxia.

(2) permit operation at high altitudes.

Regarding the above statements,

*c. both No. 1 and No. 2 are true.

578. (8576) (1) Oxygen used in aircraft systems is at least 99.5 percent pure and is practically water free.

(2) Oxygen used in aircraft systems is 99.5 percent pure and is hospital quality.

Regarding the above statements,

*a. only No. 1 is true.

579. (8577) Oxygen systems in unpressurized aircraft are generally of the

*a. continuous-flow and pressure-demand types.

580. (8578) The purpose of the airflow metering aneroid assembly found in oxygen diluter demand regulators is to

*b. regulate airflow in relation to cabin altitude when in diluter demand position.

581. (8579) If a high-pressure oxygen cylinder is to be installed in an airplane, it must meet the specifications of the

*b. Department of Transportation.

582. (8580) Before a high-pressure oxygen cylinder is serviced, it must be the correct type and have been

*a. hydrostatically tested within the proper time interval.

583. (8581) A contaminated oxygen system is normally purged with

*a. oxygen.

584. (8582) How should you determine the amount of oxygen in a portable, high-pressure cylinder?

*b. Read the pressure gauge mounted on the cylinder.

585. (8583) What may be used as a lubricant on oxygen system tapered pipe thread connections?

*c. Teflon tape.

586. (8584) On transport category aircraft what might be an indication of an over pressure event of the aircraft oxygen system?

*a. The green thermal expansion disk missing.

587. (8585) Which of the following are characteristic of a chemical or solid state oxygen system?

1. An adjustable oxygen release rate.

2. A volume storage capacity about three times that of compressed oxygen.

3. The system generators are inert below 400¡F even under severe impact.

4. A distribution and regulating system similar to gaseous oxygen systems.

*a. 2 & 3.

588. (8586) An aircraft magnetic compass is swung to up-date the compass correction card when

. *c. equipment is added that could effect compass deviation

589. (8587) The operating mechanism of most hydraulic pressure gauges is

*a. a Bourdon tube.

590. (8588) What is the fixed line mark attached to the compass bowl of a magnetic compass called?

*b. Lubber line.

591. (8589) (1) Aircraft instruments are color-coded to direct attention to operational ranges and limitations.

(2) Aircraft instruments range markings are not specified by Title 14 of the Code of Federal Regulations but are standardized by aircraft manufacturers.

Regarding the above statements,

*a. only No. 1 is true.

592. (8590) When swinging a magnetic compass, the compensators are adjusted to correct for

*a. magnetic influence deviation.

593. (8591) What will be the result if the instrument static pressure line becomes disconnected inside a pressurized cabin during cruising flight?

*a. The altimeter and airspeed indicator will both read low.

594. (8592) The maximum deviation (during level flight) permitted in a compensated magnetic direction indicator installed on an aircraft certificated under Federal Aviation Regulation Part 23 is

*c. 10°

595. (8593) Magnetic compass bowls are filled with a liquid to

*c. dampen the oscillation of the float.

596. (8594) Instrument static system leakage can be detected by observing the rate of change in indication of the

*c. altimeter after suction has been applied to the static system to cause a prescribed equivalent altitude to be indicated.

597. (8595) The maximum altitude loss permitted during an unpressurized aircraft instrument static pressure system integrity check is

*c. 100 feet in 1 minute.

598. (8596) Which statement regarding an aircraft instrument vacuum system is true?

*a. Dry-type vacuum pumps with carbon vanes are very susceptible to damage from solid airborne particles and must take in only filtered air.

599. (8597) When an aircraft altimeter is set at 29.92" Hg on the ground, the altimeter will read

*a. pressure altitude.

600. (8598) Which of the following instrument discrepancies could be corrected by an aviation mechanic?

1. Red line missing.

2. Case leaking.

3. Glass cracked.

4. Mounting screws loose.

5. Case paint chipped.

6. Leaking at line B nut.

7. Will not adjust.

8. Fogged.

*c. 1, 4, 5, 6.

601. (8599) Which of the following instrument discrepancies would require replacement of the instrument?

1. Red line missing.

2. Case leaking.

3. Glass cracked.

4. Mounting screws loose.

5. Case paint chipped.

6. Leaking at line B nut.

7. Will not zero out.

8. Fogged.

*a. 2, 3, 7, 8.

602. (8600) Which instrument condition is acceptable and would not require correction?

1. Red line missing.

2. Case leaking.

3. Glass cracked.

4. Mounting screws loose.

5. Case paint chipped.

6. Leaking at line B nut.

7. Will not zero out.

8. Fogged.

*b. 5

603. (8601) A barometric altimeter indicates pressure altitude when the barometric scale is set at

*a. 29.92" Hg.

604. (8602) A Bourdon tube instrument may be used to indicate

1. pressure.

2. temperature.

3. position.

*a. 1 and 2.

605. (8603) A turn coordinator instrument indicates

*c. both roll and yaw.

606. (8604) Aircraft temperature thermocouple leads may

*a. not be altered and are designed for a specific installation.

607. (8605) A synchro transmitter is connected to a synchro receiver

*c. electrically with wires.

608. (8606) The operation of an angle-of-attack indicating system is based on detection of differential pressure at a point where the airstream flows in a direction

*a. not parallel to the true angle of attack of the aircraft.

609. (8607) Turbine engine exhaust gas temperatures are measured by using

*b. chromel/alumel thermocouples.

610. (8608) Fuel flow transmitters are designed to transmit data

*b. electrically.

611. (8609) Which of the following causes of aircraft magnetic compass inaccuracies may be compensated for by mechanics?

*a. Deviation.

612. (8610) Who is authorized to repair an aircraft instrument?

1. A certified mechanic with an airframe rating.

2. A certificated repairman with an airframe rating.

3. A certificated repair station approved for that class instrument.

4. A certificated airframe repair station.

*c. 3

613. (8611) What does a reciprocating engine manifold pressure gauge indicate when the engine is not operating?

*c. The existing atmospheric pressure.

614. (8612) The requirements for testing and inspection of instrument static systems required by

*c. Part 43, appendix E.

615. (8613) Which condition would be most likely to cause excessive vacuum in a vacuum system?

*b. Vacuum relief valve improperly adjusted.

616. (8614) Data transmitted between components in an EFIS are converted into

*a. digital signals.

617. (8615) The function of a CRT in an EFIS is to

*b. display alphanumeric data and representations of aircraft instruments.

618. (8616) The function of a symbol generator (SG) in an EFIS is to

*c. receive and process input signals from aircraft and engine sensors and send the data to the appropriate display.

(8617) The function of a display controller in an EFIS is to

*b. allow the pilot to select the appropriate system configuration for the current flight situation.

620. (8618) A radar altimeter determines altitude by

*a. transmitting a signal and receiving back a reflected signal.

621. (8619) A radar altimeter indicates

*c. altitude above ground level.

622. (8620) Resistance-type temperature indicators using Wheatstone bridge or ratiometer circuits may be used to indicate the temperatures of which of the following?

1. Free air.

2. Exhaust gas temperature.

3. Carburetor air.

4. Coolant (engine).

5. Oil temperature.

6. Cylinder head temperature.

*b. 1, 3, 4, and 5.

623. (8621) When flags such as NAV, HDG, or GS are displayed on an HSI, the indication is

*a. that function is inoperative.

624. (8622) Instrument panel shock mounts absorb

*b. low frequency, high-amplitude shocks.

625. (8623) Which procedure should you use if you find a vacuum-operated instrument glass loose?

*c. Install another instrument.

626. (8624) Which instruments are connected to an aircraft's pitot-static system?

1. Vertical speed indicator.

2. Cabin altimeter.

3. Altimeter.

4. Cabin rate-of-change indicator.

5. Airspeed indicator.

*c. 1, 3, and 5.

627. (8625) Which of the following instruments will normally have range markings?

*b. Cylinder head temperature gauge, airspeed indicator.

628. (8626) How would an airspeed indicator be marked to show the best rate-of-climb speed (one engine inoperative)?

*b. A blue radial line.

629. (8627) The green arc on an aircraft temperature gauge indicates

*b. the desirable temperature range.

630. (8628) What must be done to an instrument panel that is supported by shock mounts?

*a. Bonding straps must be installed across the instrument mounts as a current path.

631. (8629) What marking color is used to indicate if a cover glass has slipped?

*b. White.

632. (8630) Aircraft instrument value should be marked and graduated in accordance with

*c. the specific aircraft maintenance or flight manual.

633. (8631) Aircraft instrument panels are generally shock-mounted to absorb

*b. low-frequency, high-amplitude shocks.

634. (8632) The method of mounting aircraft instruments in their respective panels depends on the

*b. design of the instrument case.

635. (8633) How is a flangeless instrument case mounted in an instrument panel?

*b. By an expanding-type clamp secured to the back of the panel and tightened by a screw from the front of the instrument panel.

636. (8634) Cases for electrically operated instruments are made of

*b. Iron or steel cases.

637. (8635) When installing an instrument in an aircraft, who is responsible for making sure it is

*b. The instrument installer.

638. (8636) Where may a person look for the information necessary to determine the required markings on an engine instrument?

1. Engine manufacturer's specifications.

2. Aircraft flight manual.

3. Instrument manufacturer's specifications.

4. Aircraft maintenance manual.

*a. 2 or 4.

639. (8637) A certificated mechanic with airframe and powerplant ratings may

*c. not perform repairs to aircraft instruments.

640. (8638) The red radial lines on the face of an engine oil pressure gauge indicates

*c. minimum and/ or maximum safe operating limits.

641. (8639) A certificated mechanic may perform

*b. 100-hour inspections of instruments.

.642. (8640) An aircraft instrument panel is electrically bonded to the aircraft structure to

*b. provide current return paths.

643. (8641) How many of the following are controlled by gyroscopes?

1. Attitude indicator.

2. Heading indicator.

3. Turn needle of the turn-and-slip indicator.

*a. Three.

644. (8642) The lubber line on a directional gyro is used to

*a. represent the nose of the aircraft.

645. (8643) Which instruments are connected to an aircraft's static pressure system only?

1. Vertical speed indicator.

2. Cabin altimeter.

3. Altimeter.

4. Cabin rate-of-change indicator.

5. Airspeed indicator.

*a. 1 and 3.

646. (8644) When an unpressurized aircraft's static pressure system is leak checked to comply with the requirements of Section 91.411, what aircraft instrument may be used in lieu of a pitot-static system tester?

1. Vertical speed indicator.

2. Cabin altimeter.

3. Altimeter.

4. Cabin rate-of-change indicator.

5. Airspeed indicator.

*c. 3

647. (8645) If a static pressure system check reveals excessive leakage, the leak(s) may be located by

*b. isolating portions of the line and testing each portion systematically starting at the instrument connections.

648. (8646) When performing the static system leakage check required by Section 91.411, the technician utilizes

*c. negative pressure.

649. (8647) What is the primary purpose of an autopilot?

*a. To relieve the pilot of control of the aircraft during long periods of flight.

650. (8648) Which of the following provides manual maneuverability of the aircraft while the autopilot is engaged?

*c. Flight controller.

651. (8649) In an autopilot, which signal nullifies the input signal to the ailerons?

*c. Followup signal.

652. (8650) In which control element of an autopilot system is an attitude indicator?

*b. Sensing.

653. (8651) What is the operating principle of the sensing device used in an autopilot system?

*b. The relative motion between a gyro and its supporting system.

654. (8652) What will occur if an aircraft attitude is changed by its autopilot system in order to correct for an error and the involved control surfaces are returned to streamline by the time the aircraft has reached its correct position?

*c. Normal operation.

655. (8653) What component of an autopilot system applies torque to the control surfaces of an aircraft?

*a. Servo.

656. (8654) What is the main purpose of a servo in an autopilot system?

*c. Move the control surface as commanded.

657. (8655) Which channel of an autopilot detects changes in pitch attitude of an aircraft?

*a. Elevator.

658. (8656) The elevator channel of an autopilot controls the aircraft about which axis of rotation?

*c. Lateral.

659. (8657) What component is the sensing device in an electromechanical autopilot system?

*b. Gyro.

660. (8658) A fully integrated autopilot controls the aircraft around how many axes?

*b. Three.

661. (8659) Dutch roll, a combination yawing and rolling oscillation that affects many sweptwing aircraft, is counteracted with

*c. a yaw damper system.

662. (8660) When operationally checking an autopilot system on the ground, after the aircraft's main power has been switched on, the autopilot should be engaged

*a. only after the gyros come up to speed and the amplifier warms up.

663. (8661) Installed radio equipment is protected from damage due to jolts and vibration by

*a. shock mounts.

664. (8662) (1) Use solder to attach bonding jumpers on radio equipment.

(2) Radio equipment is bonded to the aircraft in order to provide a low-impedance ground and to minimize radio interference from static electrical charges.

Regarding the above statements,

*c. only No. 2 is true.

665. (8663) When must the radio station license be displayed in an aircraft equipped with a two-way radio?

*a. When the aircraft is operated outside the U.S.

666. (8664) When would a U.S. resident NOT be required to hold a Federal Communications Commission (FCC) Restricted Radio Telephone Operator Permit to operate two-way aircraft VHF radio equipment?

*b. When flying or communicating within the United States.

667. (8665) Part of the ADF system used on aircraft includes

*c. sense and loop antennas.

668. (8666) When installing coaxial cable, it should be secured firmly along its entire length

*c. at 2-foot intervals.

669. (8667) When must the emergency locator transmitter (ELT) battery be replaced (other than reading the replacement date)?

*a. When the transmitter has been in use for more than one cumulative hour.

670. (8668) An emergency locator transmitter (ELT) battery must be capable of furnishing power for signal transmission for at least

*b. 48 hours.

671. (8669) The preferred location of an ELT is

. *c. as far aft as possible, but forward of the vertical fin

672. (8670) An emergency locator transmitter (ELT) is normally activated by an inertial switch or equivalent mechanism if subjected to a force of a prescribed intensity and duration. It must activate when the force is applied

*a. parallel to the longitudinal axis of the aircraft.

673. (8671) How may the battery replacement date be verified for an emergency locator transmitter (ELT)?

*b. By observing the battery replacement date marked on the outside of the transmitter.

674. (8672) How may the operation of an installed emergency locator transmitter (ELT) be verified during aircraft inspection?

*c. By tuning a communications receiver to the civil emergency frequency and activating the ELT momentarily within five minutes after the hour.

675. (8673) Static dischargers help eliminate radio interference by dissipating static electricity into the atmosphere at

*a. low current levels.

676. (8674) Long Range Navigation (LORAN) systems determine aircraft location by

*b. means of pulsed signals transmitted from ground stations.

677. (8675) An aircraft antenna installation must be grounded

*a. to the airframe.

678. (8676) VHF radio signals are commonly used in

*c. both VOR navigation and ATC communications.

679. (8677) On modern large aircraft, what electronic device typically monitors flight parameters and performs autopilot functions?

*a. Flight management computer.

680. (8678) In the landing configuration GPWS typically monitors the radio (radar) altimeter; air data computer; instrument landing system; and

*b. landing gear and flap positions.

681. (8679) In general, the purpose of an aircraft transponder is to

*c. receive an interrogation signal from a ground station and automatically send a reply back.

682. (8680) When an antenna is installed, it should be fastened

*c. so that loads imposed are transmitted to the aircraft structure.

683. (8681) After an automatic direction finding antenna has been installed, the

*b. loop must be calibrated.

684. (8682) Doublers are used when antennas are installed to

*c. reinstate the structural strength of the aircraft skin.

685. (8683) One antenna can be used for the radio range and standard broadcast bands in light aircraft because the

*a. two ranges are close together.

686. (8684) What characteristics of the installation of a rigid antenna on a vertical stabilizer should be evaluated?

*c. Flutter and vibration.

687. (8685) A gasket or sealant is used between the antenna mast and fuselage skin

*a. to prevent the entry of moisture.

688. (8686) The preferred location of a VOR antenna on light aircraft is on

*b. top of the cabin with the apex of the V pointing forward.

689. (8687) The purpose of a localizer is to

*c. align the airplane with the center of the runway.

690. (8688) (Refer to Figure 15.) What is the approximate drag load on an antenna with a frontal area of .125 square feet installed on an aircraft with a speed of 225 MPH?

*a. 2.069 pounds.

691. (8689) (Refer to Figure 15.) What is the approximate drag load on an antenna with a frontal area of .137 square feet installed on an aircraft with a speed of 275 MPH?

*a. 3.387 pounds.

692. (8690) A DME antenna should be located in a position on the aircraft that will

*a. not be blanked by the wing when the aircraft is banked.

693. (8691) When bending coaxial cable, the bend radius should be at least

*a. 10 times the diameter of the cable.

694. (8692) When installing a DME antenna, it should be aligned with the

*c. centerline on the airplane.

695. (8693) (Refer to Figure 16.) Which of the antennas shown is a typical DME antenna?

*a. 1

696. (8694) (Refer to Figure 16.) Which of the antennas shown is a typical glideslope antenna?

*a. 2

697. (8695) The addition of avionics and associated antenna systems forward of the CG limit will affect

*a. empty weight and useful load.

698. (8696) How much clearance from the seat bottom is required when installing radio equipment under a seat?

*c. 1 inch with the seat occupied and subjected to maximum downward seat spring deflection.

699. (8697) The purpose of a glideslope system is to

*c. assist the pilot in making a correct angle of descent to the runway.

700. (8698) Fuel jettisoning is usually accomplished

*a. through a common manifold and outlet in each wing.

701. (8699) The primary purpose of an aircraft's fuel jettison system is to quickly achieve a

*a. lower landing weight.

702. (8700) (1) The fuel jettison valve must be designed to allow flight personnel to close the valve during any part of the jettisoning operation.

(2) During the fuel jettisoning operation, the fuel must discharge clear of any part of the airplane.

Regarding the above statements,

*a. both No. 1 and No. 2 are true.

703. (8701) Which of the following is employed to maintain lateral stability when jettisoning fuel?

*a. Two separate independent systems.

704. (8702) A fuel jettison system is required under certain conditions if the maximum takeoff weight exceeds the maximum landing weight. What regulations cover the requirements of fuel jettisoning?

*b. Federal Aviation Regulation Part 23, 25 and CAM 4b.

705. (8703) Fuel is moved overboard in most fuel jettison systems by

*a. boost pumps.

706. (8704) Fuel jettisoning past the limits prescribed by Federal Aviation Regulations is usually prevented by

*b. dump limit valves or a low-level circuit.

707. (8705) Which procedure must be followed when defueling aircraft with sweptback wings?

*c. Defuel the outboard wing tanks first.

708. (8706) (Refer to Figure 17.) What is the purpose of the pump crossfeed valve?

*b. Allow operation of engines from one tank.

709. (8707.1) Normal fuel crossfeed system operation in multiengine aircraft

*c. provides a means to maintain a balanced fuel load condition.

710. (8708) What is the primary purpose of the crossfeed system?

*a. To allow the feeding of any engine from any tank.

711. (8709.1) Fuel system components must be bonded and grounded in order to

*a. drain off static charges.

712. (8710.1) A typical large transport aircraft fuel manifold system allows how many of the following?

1. All tanks can be serviced through a single connection.

2. Any engine can be fed from any tank.

3. All engines can be fed from all tanks simultaneously.

4. A damaged tank can be isolated from the rest of the fuel system.

*c. 1, 2, 3, and 4.

713. (8711) The use of turbine fuels in aircraft has resulted in some problems not normally associated with aviation gasolines. One of these problems is

*c. microbial contaminants.

714. (8712) What is used in many aircraft to prevent bubbles in the fuel after it leaves the tank when atmospheric pressure is lower than fuel vapor pressure?

*c. Boost pumps.

715. (8713) Which of the following precautions is most important during refueling operations?

*b. Fuel to be used must be appropriately identified.

716. (8714) Before fueling an aircraft by using the pressure fueling method, what important precaution should be observed?

*a. The truck pump pressure must be correct for that refueling system.

717. (8715) What flight safety-related advantage does a pressure fueling system provide?

*b. Reduces the chances for fuel contamination.

718. (8716) Aircraft pressure fueling systems instructional procedures are normally placarded on the

*a. fuel control panel access door.

719. (8717) Pressure fueling of aircraft is usually accomplished through

*b. at least one single point connection.

720. (8718) Which of the following may be used for the repair of fuel leaks on most integral fuel tanks?

*c. Riveting and resealing.

721. (8719) How is the outlet fuel pressure regulated on a submerged, single-speed, centrifugal-type fuel pump?

*c. By the pump's design and internal clearances.

722. (8720) What is one purpose of a fuel tank vent?

*a. To maintain atmospheric pressure.

723. (8721) When inspecting a removable rigid fuel tank for leaks, what procedure should be followed?

*a. pressurize the tank with air and brush with soapy water.

724. (8722) If it is necessary to enter an aircraft's fuel tank, which procedure should be avoided?

*c. Conduct the defueling and tank purging operation in an air-conditioned building.

725. (8723) What is the recommended practice for cleaning a fuel tank before welding?

*c. Steam clean the tank interior.

726. (8724) An aircraft's integral fuel tank is

*b. a part of the aircraft structure.

727. (8725) Which gas is used for purging an aircraft fuel tank?

*b. Carbon dioxide.

728. (8726) Why is the main fuel strainer located at the lowest point in the fuel system?

*a. It traps any small amount of water that may be present in the fuel system.

729. (8727) The purpose of a diaphragm in a vane-type fuel pump is to

*c. compensate fuel pressures to altitude changes.

730. (8728) When moving the mixture control on a normally operating engine into the idle cutoff position, engine RPM should

*a. slightly increase before the engine starts to die.

731. (8729) Entrained water in aviation turbine fuel is a hazard because of its susceptibility to freezing as it passes through the filters. What are common methods of preventing this hazard?

*c. Anti-icing fuel additives and fuel heater.

732. (8730) As a general rule, which statement is true regarding fuel leaks?

*c. Stains, seeps, and heavy seeps, (in addition to running leaks) are considered flight hazards when located in unvented areas of the aircraft.

733. (8731) The presence of fuel stains around a fuel nozzle would indicate

*c. clogged fuel nozzle.

734. (8732) What should be used to inert an integral fuel tank before attempting repairs?

*a. CO(2).

735. (8733) What should be used to remove flux from an aluminum tank after welded repairs?

*b. 5 percent solution of nitric or sulfuric acid.

736. (8734) What method would be used to check for internal leakage of a fuel valve without removing the valve from the aircraft?

*a. Place the valve in the OFF position, drain the strainer bowl, and with boost pump on, watch to see if fuel flows to the strainer bowl.

737. (8735) Why are jet fuels more susceptible to water contamination than aviation gasoline?

*a. Jet fuel has a higher viscosity than gasoline.

738. (8736) When installing a rigid fuel line, 1/2 inch in diameter, at what intervals should the line be supported?

*c. 16 inches.

739. (8737) The probe of a capacitance-type fuel level gauge is essentially a

*c. capacitor with fuel and air acting as a dielectric.

740. (8738) Which statement concerning an electronic capacitance-type fuel quantity indicating system is true?

*a. It has no moving parts in the tank.

741. (8739) What type of remote-reading fuel quantity indicating system has several probes installed in each fuel tank?

*b. Electronic.

742. (8740) Which aircraft fuel quantity indicating system incorporates a signal amplifier?

*a. Electronic.

743. (8741) A drip gauge may be used to measure

*a. the amount of fuel in the tank.

744. (8742) The electronic-type fuel quantity indicating system consists of a bridge circuit,

*a. an amplifier, an indicator, and a tank unit.

745. (8743) A probe or a series of probes is used in what kind of fuel quantity indicating system?

*b. Capacitor.

746. (8744) Why is the capacitance fluid quantity indicating system more accurate in measuring fuel level than a mechanical type?

*c. It measures by weight instead of volume.

747. (8745) One advantage of electrical and electronic fuel quantity indicating systems is that

*c. several fuel tank levels can be read on one indicator.

748. (8746.1) A fuel totalizer is a component which indicates the

*c. amount of fuel in all tanks.

749. (8747) What is the dielectric (nonconducting material) in a capacitance-type fuel quantity indicating system?

*c. Fuel and air in the tank.

750. (8748) A capacitance-type fuel quantity indicating system measures fuel in

*a. pounds.

751. (8749) What are the four general types of fuel quantity gauges?

*a. 1, 2, 3, 4.

752. (8750) How does temperature affect fuel weight?

*a. Cold fuel is heavier per gallon.

753. (8751) One advantage of electrical and electronic fuel quantity indicating systems is that the indicator

*a. can be located any distance from the tank(s).

754. (8752) When fuel quantity is measured in pounds instead of gallons, the measurement will be more accurate because fuel volume

*a. varies with temperature change.

755. (8753) An electrical-type fuel quantity indicating system consists of an indicator in the cockpit and a

*a. float-operated transmitter installed in the tank.

756. (8754) What is the purpose of a float-operated

transmitter installed in a fuel tank?

*a. It sends an electric signal to the fuel quantity indicator.

757. (8755) In an electronic-type fuel quantity indicating system, the tank sensing unit is a

*a. capacitor.

758. (8756) What must each fuel quantity indicator be calibrated to read during level flight when the quantity of fuel remaining is equal to the unusable fuel supply?

*c. Zero.

759. (8757) What unit would be adjusted to change the fuel pressure warning limits?

*b. Pressure-sensitive mechanism.

760. (8758) Select one means of controlling the fuel temperature on turbine-powered aircraft.

*c. Engine bleed air to a heat exchanger.

761. (8759) What is the purpose of flapper-type check valves in integral fuel tanks?

*b. To prevent fuel from flowing away from the boost pumps.

762. (8760) What unit is generally used to actuate the fuel pressure warning system?

*b. Pressure-sensitive mechanism.

763. (8761) What method is used on turbine-powered aircraft to determine when the condition of the fuel is approaching the danger of forming ice crystals?

*c. Fuel temperature indicator.

764. (8762) Which of the following would give the first positive indication that a change-over from one fuel tank to another is needed?

*a. Fuel pressure warning.

765. (8763) A fuel pressure warning switch contacts close and warning light is turned on when

*c. the fuel pressure drops below specified limits.

766. (8764) A transmitter in a fuel pressure warning system serves what function?

*b. Converts fluid pressure to an electrical signal.

767. (8765) Where is fuel pressure taken for the pressure warning signal on most aircraft engines?

*b. Fuel pressure line of the carburetor.

768. (8766) Which of the following is necessary to effectively troubleshoot a fuel pressure warning system?

*a. The manufacturer's maintenance manuals.

769. (8767) Which of the following would be most useful to locate and troubleshoot an internal fuel leak in an aircraft fuel system?

*c. A fuel system schematic.

770. (8768) In some aircraft with several fuel tanks, the possible danger of allowing the fuel supply in one tank to become exhausted before the selector valve is switched to another tank is prevented by the installation of

*a. a fuel pressure warning signal system.

771. (8769) (1) The function of a fuel heater is to protect the engine fuel system from ice formation.

(2) An aircraft fuel heater cannot be used to thaw ice in the fuel screen.

Regarding the above statements,

*a. only No. 1 is true.

772. (8770) (1) Gas-turbine-engine fuel systems are very susceptible to the formation of ice in the fuel filters.

(2) A fuel heater operates as a heat exchanger to warm the fuel.

Regarding the above statements,

*c. both No. 1 and No. 2 are true.

773. (8771) (1) A fuel heater can use engine bleed air as a source of heat.

(2) A fuel heater can use engine lubricating oil as a source of heat.

Regarding the above statements,

*b. both No. 1 and No. 2 are true.

774. (8772) (1) A fuel pressure gauge is a differential pressure indicator.

(2) A fuel pressure gauge indicates the pressure of the fuel entering the carburetor.

Regarding the above statements,

*b. both No. 1 and No. 2 are true.

775. (8773) (1) A fuel pressure relief valve is required on an aircraft positive-displacement fuel pump.

(2) A fuel pressure relief valve is required on an aircraft centrifugal fuel boost pump.

Regarding the above statements,

*a. only No. 1 is true.

776. (8774) The primary purpose of a fuel tank sump is to provide a

*b. place where water and dirt accumulations in the tank can collect and be drained.

777. (8775) Why are integral fuel tanks used in many large aircraft?

*c. To reduce weight.

778. (8776) If an aircraft is fueled from a truck or storage tank which is known to be uncontaminated with dirt or water, periodic checks of the aircraft's fuel tank sumps and system strainers

*b. are still necessary due to the possibility of contamination from other sources.

779. (8777) Aircraft defueling should be accomplished

*c. in the open air for good ventilation.

780. (8778) Integral fuel tanks on transport aircraft are

*c. formed by the aircraft structure.

781. (8779) What precautions must be observed if a gravity-feed fuel system is permitted to supply fuel to an engine from more than one tank at a time?

*a. The tank airspaces must be interconnected.

782. (8780) The purpose of the baffle plate in a fuel tank is to

*b. resist fuel surging within the fuel tank.

783. (8781) What minimum required markings must be placed on or near each appropriate fuel filler cover on utility category aircraft?

*c. The word 'Avgas' and the minimum fuel grade.

784. (8782) What is one disadvantage of using aromatic aviation fuels?

*b. Deteriorates rubber parts.

785. (8783) Fuel-boost pumps are operated

*a. to provide a positive flow of fuel to the engine.

786. (8784) Flapper valves are used in fuel tanks to

*c. act as check valves.

787. (8785) Why are centrifugal-type boost pumps used in fuel systems of aircraft operating at high altitude?

*b. To supply fuel under pressure to engine-driven pumps.

788. (8786) Why is it necessary to vent all aircraft fuel tanks?

*c. To limit pressure differential between the tank and atmosphere.

789. (8787) According to Part 23, what minimum required markings must be placed at or near each appropriate fuel filler cover for reciprocating engine-powered airplanes?

*a. The word 'Avgas' and the minimum fuel grade.

790. (8788) The location of leaks and defects within the internal portions of the fuel system can usually be determined by

*c. observing the pressure gauge and operating the selector valves.

791. (8789) What type of fuel-booster pump requires a pressure relief valve?

*b. Sliding vane.

792. (8790) To prevent vapor lock in fuel lines at high altitude, some aircraft are equipped with

*c. booster pumps.

793. (8791) A fuel temperature indicator is located in the fuel tanks on some turbine-powered airplanes to tell when the fuel may be

*b. in danger of forming ice crystals.

794. (8792) When inspecting a fuel system, you should check all valves located downstream of boost pumps with the pumps

*c. operating.

795. (8793) The type of fuel-boost pump that separates air and vapor from the fuel before it enters the line to the carburetor is the

*b. centrifugal-type pump.

796. (8794) (1) On a large aircraft pressure refueling system, a pressure refueling receptacle and control panel will permit one person to fuel or defuel any or all fuel tanks of an aircraft.

(2) Because of the fuel tank area, there are more advantages to a pressure fueling system in light aircraft.

Regarding the above statements,

*a. only No. 1 is true.

797. (8795) When routing a fuel line between two rigidly mounted fittings the line should

a. have at least one bend between such fittings.

798. (8796) (1) If aviation gasoline vaporizes too readily, fuel lines may become filled with vapor and cause increased fuel flow.

(2) A measure of a gasoline's tendency to vapor lock is obtained from the Reid vapor pressure test.

Regarding the above statements,

*a. only No. 2 is true.

799. (8797) Microbial growth is produced by various forms of microorganisms that live and multiply in the

water interfaces of jet fuels. Which of the following could result if microbial growth exists in a jet fuel tank and is not corrected?

1. Interference with fuel flow.

2. Interference with fuel quantity indicators.

3. Engine seizure.

4. Electrolytic corrosive action in a metal tank.

5. Lower grade rating of the fuel.

6. Electrolytic corrosive action in a rubber tank.

*a. 1, 2, 4.

800. (8798) The vapor pressure of aviation gasoline is *a. lower than the vapor pressure of automotive gasoline.

801. (8799) What can be done to eliminate or minimize the microbial growth problem in an aircraft jet fuel tank? *a. Use anti-icing and antibacterial additives.

802. (8800) What is the maximum vapor pressure allowable for an aircraft fuel? *a. 7 PSI.

803. (8801) If a bladder-type fuel tank is to be left empty for an extended period of time, the inside of the tank should be coated with a film of

*a. engine oil.

804. (8802) How may the antiknock characteristics of a fuel be improved? *a. By adding a knock inhibitor.

805. (8746.2) A digital fuel totalizer automatically indicates the amount of fuel used, fuel remaining, current rate of consumption, and fuel *a. weight, aboard at takeoff.

806. (8707.2) How many vents, arranged so that they are not likely to become plugged at the same time, must be used in multiengine fuel systems?

*a. Two.

807. (8709.2) How many engine driven fuel pumps per engine are required for engines requiring fuel pumps? *b. One fuel pump for each engine.

808. (8710.2) A fuel system must be designed to prevent fuel-vapor ignition caused by *c. lightning.

809. (8710.3) What is the minimum distance allowed between a fuel tank and the fire wall separating the engine? *a. One-half inch.

810. (8710.4) Fuel baffles are installed in tanks to prevent _ caused by changes in the altitude of the aircraft. *b. surging

811. (8710.5) Many fuel tanks incorporate _ valves to prevent fuel from flowing away from the boost pump or tank outlet when the aircraft is in a high 'G' maneuver.

*a. flapper

812. (8710.6) Fuel heaters are used with fuel systems for turbine engines to prevent _ in the fuel from clogging system filters.

*b. ice crystals

813. (8710.7) A transducer in a fuel pressure system serves what function? *c. Converts fluid pressure directly through a transmitter to the indicator.

814. (8803) Some electric motors have two sets of field

windings wound in opposite directions so that the *c. motor can be operated in either direction.

815. (8804) One purpose of a growler test is to determine the presence of *c. a shorted armature.

816. (8805) Electric wire terminals for most aircraft applications must be what type? *c. Ring.

817. (8806) What is the principal advantage of the series-wound dc motor? *a. High starting torque.

818. (8807) If a generator is equipped with a vibrator-type voltage regulator, the actual time the voltage regulator points remain open

*a. depends on the load carried by the generator.

819. (8808) What is a cause of generator brush arcing? *c. Low spring tension.

820. (8809) What is required when operating two aircraft ac generators in parallel? *b. Frequency and voltage must both be equal.

821. (8810) The starting current of a series-wound dc motor, in passing through both the field and armature windings, produces a *c. high starting torque.

822. (8811) Which motor would be most likely to have an armature brake? *b. Landing light retraction motor.

823. (8812) The method most often used in overcoming the effect of armature reaction is through the use of

*a. interpoles.

824. (8813) The only practical method of maintaining a constant voltage output from an aircraft generator under

varying conditions of speed and load is to vary the *a. strength of the magnetic field.

825. (8814) The pole pieces or shoes used in a dc generator are a part of the

of the magnetic circuit for the field. a. armature assembly.

826. (8815) How many cycles of ac voltage are produced in a six-pole alternator of the revolving-field type for each revolution of the rotor? *b. Three.

827. (8816) If the reverse current cutout relay contact points fail to open after the generator output has dropped below battery potential, current will flow through the generator armature *c. opposite the normal direction and through the shunt field in the normal direction.

828. (8817) How does the magnetic brake used to stop rotation of an electric motor armature operate? *c. A friction brake is applied by a spring and released by a magnet.

829. (8818) In a generator, what eliminates any possible sparking to the brush guides caused by the movement of the brushes within the holder? *a. The brush pigtail.

830. (8819) A series-wound dc electric motor will normally require *c. more current at low RPM than at high RPM.

831. (8820) The type of electric wire terminals used for most aircraft applications, in addition to providing good current carrying capabilities, are designed primarily *a. to prevent circuit failure due to terminal disconnection.

832. (8821) Aluminum wire must be stripped very

carefully because *c. individual strands will break easily after being nicked.

833. (8822) The commutator of a generator *b. changes alternating current produced in the armature into direct current as it is taken from the armature.

834. (8823) An ammeter in a battery charging system is for the purpose of indicating the

*c. rate of current used to charge the battery.

835. (8824) Which of the following is not one of the purposes of interpoles in a generator? *a. Reduce field strength.

836. (8825) To test generator or motor armature windings for opens, *a. place armature in a growler and connect a 110V test light on adjacent segments; light should light.

837. (8826) What is the color and orientation of the position lights for navigation on civil airplanes? *b. Left side - red, right side - green, rear aft - white.

838. (8827) To what depth is the mica insulation between the commutator bars of a dc generator undercut?

a. *c. Equal to the width of the mica.

839. (8828) A voltage regulator controls generator output by *c. varying current flow to generator field coil.

840. (8829) Which type of dc generator is not used as an airplane generator? *b. Series wound.

841. (8830) What is the most accurate type of frequency-

measuring instrument? *a. Integrated circuit chip having a clock circuit.

842. (8831) During ground operation, aircraft generator cooling is usually accomplished by *b. an integral fan.

843. (8832) What does a rectifier do? *b. Changes alternating current into direct current.

844. (8833) What type of instrument is used for measuring very high values of resistance? *a. Megohmmeter.

845. (8834) When a diode is checked for an open circuit or a short circuit, it should be

*c. disconnected from the circuit.

846. (8835) When handling a high voltage capacitor in an electrical circuit, be sure it

*c. is fully discharged before removing it from the circuit.

847. (8836) Which of the following is most likely to cause thermal runaway in a nickel-cadmium battery? *b. Excessive current draw from the battery.

848. (8837) How can it be determined if a transformer

*c. The transformer will get hot in normal operation.

849. (8838) Which of the following are the major parts of a dc motor? *a. 1, 2, 3, 7.

850. (8839) (1) There are three basic types of dc motors; series, shunt, and compound.

(2) In the series motor, the field windings, consisting of relatively few turns of heavy wire, are connected in

series with the armature winding.

Regarding the above statements, *c. both No. 1 and No. 2 are true.

851. (8840) For general electrical use in aircraft, the acceptable method of attaching a terminal to a wire is by *a. crimping.

852. (8841) Which of the following factors must be taken into consideration when determining the wire size to use for an aircraft installation?

1. Mechanical strength.

2. Allowable power loss.

3. Ease of installation.

4. Resistance of current return path through the aircraft structure.

5. Permissible voltage drop.

6. Current carrying capability of the conductor.

7. Type of load (continuous or intermittent). *a. 2, 5, 6, 7.

853. (8842) When selecting hardware for attaching bonding connections to an aircraft structure, which of the following should be considered?

1. Mechanical strength.

2. Allowable power loss.

3. Ease of installation.

4. Permissible voltage drop.

5. Amount of current to be carried.

6. Type of load (continuous or intermittent). *a. 1, 3, 5.

854. (8843) How should the splices be arranged if several are to be located in an electrical wire bundle? *a. Staggered along the length of the bundle.

855. (8844) What is the minimum bend radius for an electrical wire bundle? *a. Ten times the outside diameter of the bundle.

856. (8845) When approved, splices may be used to repair manufactured harnesses or installed wiring. The maximum number of splices permitted between any two connectors

is *a. one.

857. (8846) AN/MS electrical connectors are specifically designed to meet *b. military specifications.

858. (8847) The most common method of attaching a pin or socket to an individual wire in an MS electrical connector is by

*a. crimping.

859. (8848) The pin section of an AN/MS connector is normally installed on *b. the ground side of a circuit.

860. (8849) The voltage output of an alternator may be regulated by controlling the *b. voltage output of the dc exciter..

861. (8850) If several long lengths of electrical cable are to be installed in rigid conduit, the possibility of damage to the cable as it is pulled through the conduit will be reduced by *b. dusting the cable with powdered soapstone..

862. (8851) Grounding is electrically connecting a conductive object to the primary structure. One purpose of grounding is to *c. prevent development of radio frequency potentials.

863. (8852) What is normally used to bond noncontinuous stainless steel aircraft components? *b. Copper jumpers.

864. (8853) Aircraft fuse capacity is rated in *c. amperes.

865. (8854) When adding a rheostat to a light circuit to control the light intensity, it should be connected in *b. series with the light.

866. (8855) Circuits that must be operated only in an

emergency or whose inadvertent activation could endanger a system frequently employ *a. guarded switches.

867. (8856) If one switch is used to control all navigation lights, the lights are most likely connected *c. parallel to each other and in series with the switch.

868. (8857) Oil canning of the sides of aluminum or steel electrical junction boxes is considered to be *b. a shorting hazard.

869. (8858) Electric wiring installed in aircraft without special enclosing means (open wiring) offers the advantages of ease of installation, simple maintenance, and reduced weight. When bundling open wiring, the bundles should *a. be limited as to the number of cables to minimize damage from a single electrical fault.

870. (8859) During inspection of the terminal strips of an aircraft electrical system, it should be determined that *b. the terminal studs are anchored against rotation.

871. (8860) What protection to wires and cables does conduit provide when used in aircraft installations? *b. Mechanical.

872. (8861) Which of the following should be accomplished in the installation of aircraft wiring? *c. Locate the bundle above flammable fluid lines and securely clamp to structure.

873. (8862) If the (+) terminal of a voltmeter is connected to the (-) terminal of the source voltage and the (-) terminal of the meter is connected to the (+) terminal of the source voltage, the voltmeter will read *c. backwards.

874. (8863) When using the voltage drop method of checking circuit resistance, the *a. input voltage must be maintained at a constant value.

875. (8864) The nominal rating of electrical switches refers to continuous *c. current rating with the contacts closed.

876. (8865) Aircraft electrical junction boxes located in a fire zone are usually constructed of *c. stainless steel.

877. (8866) To help minimize radio interference a capacitor will largely eliminate and provide a steady direct current if the capacitor is connected to the generator in *a. parallel.

878. (8867) The primary considerations when selecting electric cable size are *a. current-carrying capacity and allowable voltage drop.

879. (8868) The navigation lights of some aircraft consist of a single circuit controlled by a single switch which has an ON position and an OFF position, with no additional positions possible. This switch is referred to as a *c. single-pole, single-throw (SPST), two-position switch.

880. (8869) Electric circuits are protected from overheating by means of *c. fuses.

881. (8870) How does the routing of coaxial cables differ from the routing of electrical wiring? *c. Coaxial cables are routed as directly as possible.

882. (8871) Which of the following copper electrical cable sizes should be selected to replace a No. 6 aluminum electrical cable? *b. No. 6.

883. (8872) In installations where the ammeter is in the generator or alternator lead, and the regulator system does not limit the maximum current that the generator or alternator can deliver, the ammeter can be redlined at what percent of the generator or alternator rating? *c. 100

884. (8873) Which statement relating to electric wiring is true? *b. When attaching a terminal to the end of an electric cable, it should be determined that the strength of the cable-to-terminal joint is at least equal to the tensile strength of the cable itself.

885. (8874) Bonding connections should be tested for *a. resistance value.

886. (8875) What kind of switch should you install in a single wire circuit that required the switch to be manually held in the ON position? *a. Single-pole, single-throw (SPST), two-position normally open (NO).

887. (8876) A circuit breaker is installed in an aircraft electrical system primarily to protect the *a. circuit and should be located as close to the source as possible.

888. (8877) How should a voltmeter be connected? *b. In parallel with the load.

889. (8878) A circuit protection device called a current limiter is essentially a slow-blow fuse and is designed to be used in *b. heavy power circuits.

890. (8879) If it is necessary to use an electrical connector where it may be exposed to moisture, the mechanic should

*b. use a special moisture-proof type.

891. (8880) The three kinds of circuit-protection devices used most commonly in aircraft circuits are *b. circuit breakers, fuses, and current limiters.

892. (8881) If a wire is installed so that it comes in contact with some moving parts, what protection should be given the wire? *c. Pass through conduit.

893. (8882) In the American Wire Gauge (AWG) system of numbers used to designate electrical wire sizes, the number assigned to a size is related to its *c. cross-sectional area.

894. (8883) What is the voltage drop for a No. 18 copper wire 50 feet long to carry 12.5 amperes, continuous operation?

Use the formula VD = RLA

VD = Voltage drop

R = Resistance per ft = .00644

L = Length of wire

A = Amperes *c. 4V.

895. (8884) What is the purpose of the selection of derated switches for known continuous load current applications? *c. To obtain reasonable switch efficiency and service life.

896. (8885) What is the advantage of a circuit breaker when compared to a fuse? *c. Resettable and reusable.

897. (8886) What is the advantage of a current limiter? *c. It will take overload for a short period.

898. (8887) Where electric cables must pass through holes in bulkheads, formers, ribs, firewalls, etc., the

wires should be protected from chafing by

*b. using a suitable grommet.

899. (8888) In aircraft electrical systems, automatic reset circuit breakers *a. should not be used as circuit protective devices.

900. (8889) A certain switch is described as a single-pole, double-throw switch (SPDT). The throw of a switch indicates the number of *a. circuits each pole can complete through the switch.

901. (8890) When considering an alteration, the criteria upon which the selection of electric cable size should be based are *b. current-carrying capacity and allowable voltage drop.

902. (8891) What is an important factor in selecting aircraft fuses? *c. Capacity matches the needs of the circuit.

903. (8892) The circuit breaker in the instrument lighting system protects the *b. wiring from too much current.

904. (8893) One advantage of using ac electrical power in aircraft is *b. greater ease in stepping the voltage up or down.

905. (8894) Why are the iron cores of most induction coils laminated? *c. To reduce the effects of eddy currents.

906. (8895) Certain transport aircraft use ac electrical power for all normal operation and battery furnished dc electrical power for standby emergency use. In aircraft of this type that operate no dc generators, the batteries are kept charged by *c. rectifiers which use the aircraft's ac generators as a source of power.

907. (8896) The voltage in an ac transformer secondary that contains twice as many loops as the primary will be *a. greater and the amperage less than in the primary.

908. (8897) If the positive field lead between a generator and a generator control panel breaks and is shorted while the engine is running, a voltmeter connected to generator output would indicate *b. residual voltage.

909. (8898) What is a method used for restoring generator field residual magnetism? *a. Flash the fields.

910. (8899) The major advantages of alternating current (AC) over direct current (DC) is the fact that its current and voltage can easily be increased or decreased *c. by means of a transformer.

911. (8900) Which of the following must be accomplished when installing an anticollision light? *a. Install a switch independent of the position light switch.

912. (8901) The inductor-type inverter output voltage is controlled by the *c. dc stator field current.

913. (8902) When using an ohmmeter to check the continuity of a generator field coil, the coil should *c. show very low resistance if it is a series field coil.

914. (8903) The strength of the core of an electromagnet depends upon the material from which it is constructed and which of the following? *b. The number of turns of wire in the coil and the amount of current (amperes) passing through the coil.

915. (8904) A voltage regulator controls generator voltage by changing the *c. resistance of the generator field circuit.

916. (8905) The overvoltage control automatically protects the generator system when excessive voltage is present by

*a. opening the shunt field circuit.

917. (8906) When dc generators are operated in parallel to supply power for a single load, their controls include an equalizer circuit to assure that all generators share the load equally. The equalizer circuit operates by *c. increasing the output of the low generator and decreasing the output of the high generator until they are equal.

918. (8907) What is the maximum amount of time a circuit can be in operation and still be an intermittent duty circuit? *b. Two minutes.

919. (8908) The most common method of regulating the voltage output of a compound dc generator is to vary the *a. current flowing through the shunt field coils.

920. (8909) (Refer to Figure 18.) Which of the batteries are connected together incorrectly? *c. 3

921. (8910) (Refer to Figure 19.) Upon completion of the landing gear extension cycle, the green light illuminated and the red light remained lit. What is the probable cause? *c. Short in the up limit switch.

922. (8911) If any one generator in a 24-volt dc system shows low voltage, the most likely cause is *a. an out-of-adjustment voltage regulator.

923. (8912.1) How can the direction of rotation of a dc electric motor be changed? *b. Reverse the electrical connections to either the

924. (8913) Aircraft which operate only ac generators (alternators) as a primary source of electrical power normally provide current suitable for battery charging through the use of *a. a stepdown transformer and a rectifier.

925. (8914) During inspection of an anticollision light installation for condition and proper operation, it should be determined that *c. the anticollision light can be operated independently of the position lights.

926. (8915) Major adjustments on equipment such as regulators, contactors, and inverters are best accomplished outside the airplane on test benches with necessary instruments and equipment. Adjustment procedure should be as outlined by *a. the equipment manufacturer.

927. (8916) A battery-generator system provides direct current. On installations requiring alternating current from the battery-generator system, it is necessary to have *b. an inverter.

928. (8917) An aircraft electrical circuit control relay is *a. an electronically operated switch.

929. (8918) The purpose of a rectifier in an electrical system is to change

*c. alternating current to direct current.

930. (8919) What is the ratio of turns between the primary coil winding and the secondary coil winding of a transformer designed to triple its input voltage?

*a. Primary will have one-third as many turns as its secondary.

931. (8920) In an ac circuit with no phase lead or lag, which is true?

*c. Real power equals apparent power.

932. (8921) How are generators rated?

*b. Amperes at rated voltage.

933. (8922) How is a shunt-wound dc generator connected?

*b. Both fields are shunted across the armature.

934. (8923) The poles of a generator are laminated to

*c. reduce eddy current losses.

935. (8924) What is the frequency of an alternator dependent upon?

*b. RPM.

936. (8925) The generator rating is usually found stamped on the

*b. generator.

937. (8926) Residual voltage is a result of magnetism in the

*b. field shoes.

938. (8927) In troubleshooting an electrical circuit, if an ohmmeter is properly connected across a circuit component and some value of resistance is read,

*c. the component has continuity and is not open.

939. (8928) CSD driven generators are usually cooled by

*a. oil spray.

940. (8929) A CSD unit drives a generator through the use of

*c. a variable hydraulic pump and hydraulic motor.

941. (8930) Integrated drive generators (IDG) employ a type of high output ac generator that utilizes

*c. a brushless system to produce current.

942. (8931) If the Integrated Drive Generator (IDG) scavenge oil filter is contaminated with metal, you should

*b. remove and replace the IDG.

943. (8932) When necessary during operation, CSD disconnect is usually accomplished by

*a. a switch in the cockpit.

944. (8933) A CSD unit that is disconnected in flight, due to a malfunction such as overtemperature, may be reconnected

*c. only on the ground by maintenance personnel.

945. (8912.2) Static inverters are electronic devices that change DC to AC with the

*a. use of an oscillator.

946. (8934) The purpose of antiskid generators is to

*c. measure wheel rotational speed and any speed changes.

947. (8935) In a brake antiskid system, when an approaching skid is sensed, an electrical signal is sent to the skid control valve which

*b. relieves the hydraulic pressure on the brake.

948. (8936) An antiskid system is

*b. an electrohydraulic system.

949. (8937) Antiskid braking systems are generally armed by

*b. a switch in the cockpit.

950. (8938) A typical takeoff warning indication system, in addition to throttle setting, monitors the position of which of the following?

*b. Elevators, speed brake, flaps, and stabilizer trim.

951. (8939) The primary purpose of a takeoff warning system is to alert the crew that a monitored flight control is not properly set prior to takeoff. The system is activated by

*c. a thrust lever.

952. (8940) (1) An airspeed indicator measures the

differential between pitot and static air pressures surrounding the aircraft at any moment of flight.

(2) An airspeed indicator measures the differential between pitot and cabin air pressures at any moment of flight.

Regarding the above statements,

*c. only No. 1 is true.

953. (8941) The angle-of-attack detector operates from differential pressure when the airstream

*b. is not parallel to the true angle of attack of the aircraft.

954. (8942) (1) When an airplane is slowed below approximately 20 MPH, the antiskid system automatically deactivates to give the pilot full control of the brakes for maneuvering and parking.

(2) An antiskid system consists basically of three components; wheel speed sensors, control box, and control valves.

Regarding the above statements,

*c. both No. 1 and No. 2 are true.

955. (8943) In an antiskid system, wheel skid is detected by

*a. an electrical sensor.

956. (8944) Which of the following functions does a skid control system perform?

1. Normal skid control.

2. Normal braking.

3. Fail safe protection.

4. Locked wheel skid control.

5. Touchdown protection.

6. Takeoff protection.

*b. 1, 3, 4, 5.

957. (8945) In the air with the antiskid armed, current cannot flow to the antiskid control box because the landing gear

*a. squat switch is open.

958. (8946) At what point in the landing operation does normal skid control perform its function?

*a. When wheel rotation deceleration indicates an impending skid.

959. (8947) (1) An antiskid system is designed to apply enough force to operate just below the skid point.

(2) A warning lamp lights in the cockpit when the antiskid system is turned off or if there is a system failure.

Regarding the above statements,

*c. both No. 1 and No. 2 are true.

960. (8948) When an airplane's primary flight control surfaces are set for a particular phase of flight, such as landing or takeoff, the corresponding control-surface indicating system will show

*c. trim position.

961. (8949) The pneumatic (reed) type stall warning system installed in some light aircraft is activated by

*c. negative air pressure.

962. (8950) Stall warning systems are generally designed to begin warning the pilot when a stall

*a. is imminent.

963. (8951) (Refer to Figure 19.) What is the indication of the red landing gear position light under the following conditions?

Aircraft on jacks.

Landing gear in transit.

Warning horn sounding.

*a. extinguished.

964. (8952) (Refer to Figure 19). Which repair should be made if the gear switch was placed in UP position and the gear does not retract?

*c. Replace electrical wire No. 12.

965. (8953) Which of the following conditions is most likely to cause the landing gear warning signal to sound?

*c. Landing gear not locked down and throttle retarded.

966. (8954) (Refer to Figure 20.) What will illuminate the amber indicator light?

*c. Closing the nose, left and right wheel gear full retract switches.

967. (8955) (Refer to Figure 20.) What is the minimum circumstance that will cause the landing gear warning horn to indicate an unsafe condition?

*c. Any gear not down and locked, and one throttle retarded.

968. (8956) Where is the landing gear safety switch usually located?

*a. On the main gear shock strut.

969. (8957) What safety device is actuated by the compression and extension of a landing gear strut?

*c. Ground safety switch.

970. (8958) Which repair would require a landing gear retraction test?

*c. Gear downlock microswitch.

971. (8959) Landing gear warning systems usually provide which of the following indications?

*c. Red light for unsafe gear, green light for gear down, no light for gear up.

972. (8960) In most modern hydraulically actuated landing gear systems, the order of gear and fairing door operation is controlled by

*a. sequence valves.

973. (8961) What landing gear warning device(s) is/are incorporated on retractable landing gear aircraft?

*c. A horn or other aural device and a red warning

light.

974. (8962) When a landing gear safety switch on a main gear strut closes at liftoff, which system is deactivated?

*b. Antiskid system.

975. (8963) The rotor in an autosyn remote indicating system uses

*a. an electromagnet.

976. (8964) The basic difference between an autosyn and a magnesyn indicating system is the

*a. rotor.

977. (8965) The rotor in a magnesyn remote indicating system uses

*a. a permanent magnet.

978. (8966) Microswitches are used primarily as limit switches to

*b. control electrical units automatically.

979. (8967) Which of the following are some uses for a dc selsyn system?

1. Indicates position of retractable landing gear.

2. Indicates the angle of incidence of an aircraft.

3. Indicates the altitude of an aircraft.

4. Indicates cowl flaps or oil cooler door position.

5. Indicates fuel quantity.

6. Indicates the rate of climb of an aircraft.

7. Indicates position of wing flaps.

*a. 1, 4, 5, 7.

980. (8968) (1) A dc selsyn system is a widely used electrical method of indicating a remote mechanical movement or position.

(2) A synchro-type indicating system is an electrical system used for transmitting information from one point

to another.

Regarding the above statements,

*c. both No. 1 and No. 2 are true.

981. (8969) Prior to installation of a pneumatic surface-bonded type deicer boots, on the leading edge of the wing, you should

*a. remove all paint from the area to be covered by the deicer boot.

982. (8970) Which of the following are found in a laminated integral electrically heated windshield system?

1. Autotransformer.

2. Heat control relay.

3. Heat control toggle switch.

4. 24V dc power supply.

5. Indicating light.

*c. 1, 2, 3, 5.

983. (8971) What is one check for proper operation of a pitot/static tube heater after replacement?

*a. Ammeter reading.

984. (8972) What controls the inflation sequence in a pneumatic deicer boot system?

*c. Distributor valve.

985. (8973) What is the source of pressure for inflating deicer boots on reciprocating engine aircraft?

*a. Vane-type pump.

986. (8974) Which of the following regulates the vacuum of the air pump to hold the deicing boots deflated when the pneumatic deicing system is off?

*c. Suction relief valve.

987. (8975) What may be used to clean deicer boots?

*c. Soap and water.

988. (8976) Some aircraft are protected against airframe icing by heating the leading edges of the airfoils and intake ducts. When is this type of anti-ice system

usually operated during flight?

*c. Whenever icing conditions are first encountered or expected to occur.

989. (8977) Which of the following indications occur during a normal operational check of a pneumatic deicer system?

*b. Fluctuating readings on the pressure gauge and relatively steady readings on the vacuum gauge.

990. (8978) What method is usually employed to control the temperature of an anti-icing system using surface combustion heaters?

*a. Thermo-cycling switches.

991. (8979) What is the purpose of the distributor valve in a deicing system utilizing deicer boots?

*b. To sequence the deicer boots inflations symmetrically.

992. (8980) What is the purpose of the oil separator in the pneumatic deicing system?

*a. To protect the deicer boots from oil deterioration.

993. (8981) Where are the heat sensors located on most aircraft with electrically heated windshields?

*a. Imbedded in the glass.

994. (8982) Two possible sources of heat for the operation of a wing thermal anti-icing system are

*b. compressor bleed air and aircraft electrical system.

995. (8983) What maintains normal windshield temperature control in an electrically heated windshield system?

*b. Thermistors.

996. (8984) Arcing in an electrically heated windshield panel usually indicates a breakdown in the

*c. conductive coating.

997. (8985) Which of the following connects vacuum to the deicer boots when the system is not in operation, to

hold the boots tightly against the leading edges in flight?

*c. Distributor valve.

998. (8986) How do deicer boots help remove ice accumulations?

*b. By breaking up ice formations.

999. (8987) Why are the tubes in deicer boots alternately inflated?

*a. Alternate inflation of deicer boot tubes keeps disturbance of the airflow to a minimum.

1000. (8988) Carburetor icing may be eliminated by which of the following methods?

*a. Alcohol spray and heated induction air.

1001. (8989) Why should a chemical rain repellant not be used on a dry windshield?

*b. It will restrict visibility.

1002. (8990) What is the principle characteristic of a windshield pneumatic rain removal system?

*b. An air blast forms a barrier that prevents raindrops from striking the windshield surface.

1003. (8991) What mixture may be used as a deicing fluid to remove frost from an aircraft surface?

*a. Ethylene glycol and isopropyl alcohol.

1004. (8992) Which of the following is the best means to use when removing wet snow from an aircraft?

*a. A brush or a squeegee.

1005. (8993) What are three methods of anti-icing aircraft windshields?

1. Blanket-type heating system.

2. An electric heating element in the windshield.

3. Heated air circulating system.

4. Hot water system.

5. Windshield wipers and anti-icing fluid.

6. Ribbon-type heating system.

*a. 2, 3, 5.

1006. (8994) What icing condition may occur when there is no visible moisture present?

*c. Carburetor ice.

1007. (8995) What should be used to melt the ice in a turbine engine if the compressor is immobile because of ice?

*c. Hot air.

1008. (8996) What is used as a temperature-sensing element in an electrically heated windshield?

*b. Thermistor.

1009. (8997) In what area of an aircraft would you find a carbon monoxide detector?

*b. Cockpit and/or cabin.

1010. (8998) What occurs when a visual smoke detector is activated?

*b. A lamp within the indicator illuminates automatically.

1011. (8999) The types of fire-extinguishing agents for aircraft interior fires are

*a. water, carbon dioxide, dry chemical, and halogenated hydrocarbons.

1012. (9000) When air samples contain carbon monoxide, portable carbon monoxide detectors containing yellow silica gel will turn which color?

*b. Green.

1013. (9001) Smoke detection instruments are classified by their method of

*c. detection.

1014. (9002) Smoke detectors which use a measurement of light transmissibility in the air are called

*b. photoelectrical devices.

1015. (9003) A contaminated carbon monoxide portable

test unit would be returned to service by

*b. installing a new indicating element.

1016. (9004) Which fire-detection system measures temperature rise compared to a reference temperature?

*c. Thermocouple.

1017. (9005) A carbon dioxide (CO(2)) hand-held fire extinguisher may be used on an electrical fire if the

*a. horn is nonmetallic.

1018. (9006) The proper fire-extinguishing agent to use on an aircraft brake fire is

*c. dry powder chemical.

1019. (9007) Smoke in the cargo and/or baggage compartment of an aircraft is commonly detected by which instrument?

*b. Photoelectric cell.

1020. (9008) Light refraction smoke detectors are activated when the detector

*b. senses light reflected from smoke particles passing through a chamber.

1021. (9009) Why does the Fenwal fire-detection system use spot detectors wired parallel between two separate circuits?

*c. A short may exist in either circuit without causing a false fire warning.

1022. (9010) A fire-extinguisher container can be checked to determine its charge by

*b. weighing the container and its contents.

1023. (9011) What is the color code for fire-extinguisher lines?

*a. Brown.

1024. (9012) The most common cause of false fire warnings in continuous-loop fire-detection systems is

*c. dents, kinks, or crushed sensor sections.

1025. (9013) A thermocouple in a fire-detection system

causes the warning system to operate because

*a. it generates a small current when heated.

1026. (9014) The thermocouple fire-warning system is activated by a

*c. rate-of-temperature rise.

1027. (9015) When used in fire-detection systems having a single indicator light, thermal switches are wired in

*a. parallel with each other and in series with the light.

1028. (9016) Built-in aircraft fire-extinguishing systems are ordinarily charged with

*b. halogenated hydrocarbons and nitrogen

1029. (9017) In reference to aircraft fire-extinguishing systems,

(1) during removal or installation, the terminals of discharge cartridges should be grounded or shorted.

(2) before connecting cartridge terminals to the electrical system, the system should be checked with a voltmeter to see that no voltage exists at the terminal connections.

Regarding the above statements,

*b. both No. 1 and No. 2 are true.

1030. (9018) What method is used to detect the thermal discharge of a built-in fire-extinguisher system?

*b. A rupture of the red plastic disk in the thermal discharge line.

1031. (9019) The thermal switches of a bimetallic thermal-switch type fire-detection (single-loop) system are heat-sensitive units that complete circuits at a certain temperature. They are connected in

*b. parallel with each other, but in series with the indicator lights.

1032. (9020) (Refer to Figure 21.) Using the chart, determine the temperature range for a fire-extinguishing agent storage container with a pressure of 330 PSIG. (Consider 330 PSIG for both minimum and maximum pressure.)

*c. 45 to 73¡F.

1033. (9021) (Refer to Figure 21.) Determine what pressure is acceptable for a fire extinguisher when the surrounding area temperature is 33¡F. (Rounded to the nearest whole number.)

*a. 215 to 302 PSIG.

1034. (9022) On a periodic check of fire-extinguisher containers, the pressure was not between minimum and maximum limits. What procedure should be followed?

*b. Replace the extinguisher container.

1035. (9023) In some fire-extinguishing systems, evidence that the system has been intentionally discharged is indicated by the absence of a

*c. yellow disk on the side of the fuselage.

1036. (9024) If a fire extinguisher cartridge is removed from a discharge valve, it should be

*b. used only on the original discharge valve assembly.

1037. (9025) Which of the following are fire precautions which must be observed when working on an oxygen system?

1. Display 'No Smoking' placards.

2. Provide adequate fire-fighting equipment.

3. Keep all tools and oxygen servicing equipment free from oil or grease.

4. Avoid checking aircraft radio or electrical systems.

*c. 1, 2, 3, and 4.

1038. (9026) Which fire-extinguishing agent is considered to be the least toxic?

*b. Bromotrifluoromethane (Halon 1301).

1039. (9027) Maintenance of fire-detection systems includes the

*c. replacement of damaged sensing elements.

1040. (9028) A squib, as used in a fire-protection system, is a

*b. device for causing the fire-extinguishing agent to be released.