Cdc 2A251 Comm/nav Vol.2 Self Test

Front 1

201. Major structural areas

1. List six major structural areas of an aircraft.

Back 1

1. (1) Doors, (2) nacelles, (3) fuselage, (4) stabilizers, (5) windows, and (6) wings

Front 2

2. What provisions are made in the doors’ system for quick access for inspection or servicing of aircraft

components?

Back 2

2. Small hinged doors are installed in a larger door.

Front 3

3. What are the nacelles and their functions?

Back 3

3. They’re aerodynamically smooth housings that provide support for the aircraft engines

Front 4

4. What structural area provides a means for the aircrew to view outside the aircraft?

Back 4

4. Windows.

Front 5

202. Characteristics of aircraft systems

1. What type of system provides the capability to eject crew members?

Back 5

1. Crew escape and safety

Front 6

2. How do maintenance personnel talk to each other on the aircraft?

Back 6

2. Through the use of the crew/ground communications intercom system.

Front 7

3. List the five areas where exterior lights may be used on an aircraft.

Back 7

3. (1) Landing, (2) taxi, (3) position, (4) anticollision, and (5) air refueling

Front 8

4. Name the five functions of the fuel system?

Back 8

4. (1) Provide fuel storage, (2) provide fuel supply to engines, (3) fuel dumping, (4) refuel/defuel, (5) and

automatic fuel usage/sequence control

Front 9

203. Characteristics of avionics systems

1. What’s the main purpose of the offensive avionics systems?

Back 9

1. To provide accurate data for global navigation and weapons delivery

Front 10

2. What systems allow quick and efficient troubleshooting?

Back 10

2. BIT systems

Front 11

3. What abilities do defensive avionics provide?

Back 11

3. Ability to detect, identify, prioritize, and jam hostile radars

Front 12

4. What indications are provided by the hydraulic indicating systems?

Back 12

4. Hydraulic pressure, quantity, and temperature

Front 13

204. Danger areas associated with aircraft maintenance

1. Why are ejection seats so dangerous?

Back 13

1. Because the ejection system contains an explosive charge

Front 14

2. Why is it important to follow a checklist when performing maintenance, especially around ejection

seats?

Back 14

2. To prevent accidental discharge of the ejection seat.

Front 15

3. List the seven major danger areas around an operating jet engine.

Back 15

3. (1) Intake, (2) exhaust, (3) turbine plane of rotation, (4) noise, (5) cartridge starter, (6) auxiliary air inlet doors,

and (7) heat.

Front 16

4. What distances and in what directions are normally considered safe distances from the intake of an

operating jet engine?

Back 16

4. 25 feet to the front and sides.

Front 17

5. How can you determine the plane of rotation of an engine?

Back 17

5. By the painted RED BAND around the aircraft fuselage or engine nacelle or by consulting the proper technical

order.

Front 18

6. From which direction should you approach an aircraft with hot breaks? Why?

Back 18

6. Approach from the aircraft’s nose or tail direction—never in line with the axles. The areas on both sides of the

tire and wheel (in line with the axles) are where fragments would be hurled if the tire explode

Front 19

7. What is meant by the term “armed aircraft?”

Back 19

7. The aircraft has explosive weapons, such as bombs, missiles, or ammunition, installed.

Front 20

8. On what 781 series form and block is the status of aircraft armament recorded?

Back 20

8. The AFTO Form 781H, Aerospace Vehicle Flight Status and Maintenance Document, must always have an

entry in block II (Gun or Rocket Status). This entry of HOT or COLD appears in red in the status block.

Front 21

9. What effect will RF energy have on the tissue of your body?

Back 21

9. When RF energy is absorbed in the tissues of the body, heat is produced.

Front 22

10. What can you do to minimize the danger of your exposure to RF radiation?

Back 22

10. Avoid the areas of radiating sources and observe warning signs

Front 23

11. To prevent exposure to radiated RF, what’s the minimum safe distance you should maintain from an

operating UHF antenna and an operating HF antenna?

Back 23

11. 1 foot; 5 feet.

Front 24

12. What level of noise is likely to cause permanent hearing damage, even for a short exposure?

Back 24

12. 160 dBA.

Front 25

13. What’s considered the maximum safe dBA limit?

Back 25

13. 84 dBA

Front 26

14. Where is the greatest noise level intensity produced on a jet engine?

Back 26

14. To the rear of the engines through an angle of 45° on either side.

Front 27

15. What protective devices should be worn in areas with noise levels greater than 130 dBA?

Back 27

15. A protective helmet or headset in addition to earplugs

Front 28

16. How would you identify a person who was suffering from an overdose of noise?

Back 28

16. The individual may have pain, a feeling of fullness, ringing or burning of the ears; dizziness; impairment of

concentration; occasional nausea; vomiting, or weakness of the knees

Front 29

17. What precautions should you take when working around a rotating antenna system?

Back 29

17. Turn off the power, pull the circuit breakers, tell others that you’re working in the area, and post warning signs

Front 30

18. What actions should you take when working around moving machinery?

Back 30

18. Button any shirt cuffs and remove any items that could get caught in the rotating machinery

Front 31

19. What AFOSH standard gives the guidelines for fire prevention on the flight line?

Back 31

19. 127-66.

Front 32

205. Aircraft inspection systems

1. Under what four inspection concepts are AF aircraft inspected?

Back 32

1. (1) Periodic, (2) phased, (3) iochronal, and (4) programmed depot maintenance.

Front 33

2. Match the scheduled inspections in column A with the concepts in column B. Items in column B may

be used more than once.

Column A

____ (1) Preflight.

____ (2) Periodic.

____ (3) Home station

check.

____ (4) End-of-runway.

____ (5) Basic postflight.

____ (6) Hourly

postflight.

____ (7) Thruflight.

____ (8) Minor.

____ (9) Phase.

Back 33

Column B

a. Phased.

b. Periodic.

c. Isochronal

(2. (1) a, b, c, (2) b, (3) c, (4) a, b, c, (5) a, b, (c is optional), (6) b, (7) a, b, c, (8) c, (9) a.)

Front 34

206. Identifying basic scheduled inspections

1. Name the three purposes of PR, EOR, and TH inspections.

Back 34

1. (1) Flight stability, (2) suitability, and (3) preparedness

Front 35

2. How long is the PR inspection valid on a locally flown aircraft?

Back 35

2. 24, 48, or 72 hours; the time is optional for the MAJCOMs

Front 36

3. How many hours may elapse before a cargo aircraft that’s used for regularly scheduled airlift

operations requires a PR inspection?

Back 36

3. 48 hours.

Front 37

4. What inspection is performed just prior to flight?

Back 37

4. End-of-runway

Front 38

5. What type of inspection is performed on an aircraft that lands for refueling and plans to continue its

flight immediately?

Back 38

5. Thruflight

Front 39

6. When is a BPO inspection performed?

Back 39

6. After the last flight of the flying period

Front 40

7. What type of inspection determines if the aircraft is suitable for another flight?

Back 40

7. Basic postflight

Front 41

207. Inspections based on hours of operation

1. When is the HPO inspection performed?

Back 41

1. After a specified number of flying hours have accumulated.

Front 42

2. What inspection does the HPO inspection augment?

Back 42

2. Basic postflight.

Front 43

3. The PE inspection is more extensive than what two other inspections?

Back 43

3. Hourly postflight or basic postflight

Front 44

4. What’s the main objective of the PH inspection?

Back 44

4. To reduce the time the aircraft is out of commission for any given inspection

Front 45

208. Characteristics of isochronal inspections

1. How many inspections are peculiar to the isochronal inspection concept? What are they called?

Back 45

1. Three: major, minor, and HSC

Front 46

2. When are MAJ, MIN, and HSC inspections due?

Back 46

2. Major and minor inspections are due upon accrual of a specified number of calendar days. The HSC is due upon

accrual of a specified number of calendar days and/or at the completion of a long-range mission.

Front 47

3. Describe a MAJ inspection

Back 47

3. A thorough and searching “look, see, and fix” of the weapon system to see if a condition exists that, if not

corrected, could end in failure of a part or cause a system malfunction before the next scheduled inspection

Front 48

4. Describe a MIN inspection.

Back 48

4. Checking of certain components, areas or systems of the aircraft to determine that no conditions exist that could

result in failure or malfunction before the next scheduled inspection

Front 49

5. Describe an HSC inspection

Back 49

5. It’s a combination inspection of former basic postflight and hourly postflight items.

Front 50

209. Characteristics of intermediate-level inspections

1. Who has the responsibility of performing operator inspections?

Back 50

1. The user.

Front 51

2. What directs when special inspections are performed?

Back 51

2. TCTOs, MAJCOMS, or local directives as listed in the applicable TO

Front 52

3. When are periodic inspections and special lubrication requirements accomplished?

Back 52

3. Upon accrual of specified operating power-on hours or at expiration of a calendar period

Front 53

4. What’s the purpose of an acceptance inspection?

Back 53

4. To determine if the equipment is serviceable and to check the condition of the equipment documents

Front 54

5. Who performs the transfer inspection if more than 75 percent of the inspection interval has elapsed?

Back 54

5. Transferring organization

Front 55

210. AFTO Form 244

1. What’s the purpose of the AFTO Form 244?

Back 55

1. It’s a system/equipment status record

Front 56

2. What does part V of the AFTO Form 244 provide?

Back 56

2. A continuous record of all major and minor maintenance that has been done on the unit.

Front 57

211. Air Force Technical Order 781-series maintenance forms

1. What’s the purpose of the 781-series forms?

Back 57

1. To provide a maintenance, inspection, service, configuration, status, and flight record for the particular weapon

system or support system for which they’re maintained

Front 58

2. How would you use the AFTO Form 781A form?

Back 58

2. To document each discrepancy discovered by aircrew or maintenance personnel.

Front 59

3. What is an exception for using the AFTO Form 781A?

Back 59

3. Discrepancies resulting from battle damage.

Front 60

4. Explain the maintenance technician’s responsibilities for the AFTO Forms 781A.

Back 60

4. Ensures enough copies are on the aircraft, transcribes open discrepancies, and completes all heading entries.

Front 61

5. When can you erase symbols in the symbol block?

Back 61

5. Never, even if entered in error

Front 62

6. Explain the AFTO Form 781A entry for a removal to FOM.

Back 62

6. Document as a separate discrepancy with appropriate red symbol. Reference will be made to the original

discrepancy by using the see page ____, item ____ format.

Front 63

7. What’s required when a write-up is cleared?

Back 63

7. Document the corrective action in the CORRECTIVE ACTION block and enter the date in the DATE

CORRECTED block. TO reference is only required for red X discrepancies.

Front 64

8. How would you document an operational check that checked “good”?

Back 64

8. By documenting the CORRECTIVE ACTION block with a statement such as “OP CK GOOD.”

Front 65

9. Explain the purpose of the AFTO Form 781B

Back 65

9. Used to provide COMSEC equipment status and when such use is directed by the LG or MAJCOM.

Front 66

10. Who is responsible for checking the AFTO Form 781B prior to flight? Why?

Back 66

10. The aircraft commander or designated crew member. To ascertain that the COMSEC equipment configuration

conforms to the mission requirements.

Front 67

11. Describe the purpose of the AFTO Form 781H.

Back 67

11. It’s used to document maintenance status and servicing information to provide a ready reference as to the status

of the aircraft.

Front 68

12. How does the crew chief use the AFTO Form 781H prior to each flight?

Back 68

12. Checks the quantities of fuel and oil in tanks, the oxygen, nitrogen, and water systems status to ensure entries on

the form correspond with the actual quantities onboard.

Front 69

13. What’s the purpose of the exceptional release column on the AFTO Form 781H?

Back 69

13. Serves as a certification that the authorized individual who enters a signature in this column has made sufficient

investigation to justify that the aerospace vehicle is safe for flight.

Front 70

14. What’s the purpose of the AFTO Form 781J?

Back 70

14. To document aerospace vehicle time and engine data including operating time.

Front 71

15. Who is responsible for making entries on the AFTO 781J?

Back 71

15. The maintenance technician.

Front 72

16. What’s the purpose of the AFTO Form 781K?

Back 72

16. To record essential inspection and delayed maintenance data.

Front 73

17. What’s the purpose of Block D entries on the AFTO Form 781K?

Back 73

17. Enter all delayed discrepancies, urgent action TCTOs, Category I routine action safety modification TCTOs,

outstanding routine action TCTOs, or commercial equivalents in this block

Front 74

18. At what point are Red X entries entered on the AFTO Form 781K?

Back 74

18. Don’t enter Red X entries in the 781K.

Front 75

212. Air Force Form 1492, Warning Tag

1. What is the purpose of an AF Form 1492, Warning Tag?

Back 75

1. To facilitate safe maintenance by preventing the inadvertent activation of a system that should not be activated.

Front 76

2. Where are warning tags placed on the aircraft?

Back 76

2. At a point where undesirable activation of a system is possible

Front 77

3. The perforated bottom portion of the tag is used for what purpose?

Back 77

3. To provide a “cross-check” with the aircraft forms. It is inserted through the forms binder ring and aligned with

its corresponding entry.

Front 78

213. Static electricity and electrostatic discharge sensitive devices

1. What is static electricity?

Back 78

1. The accumulation of an electrical charge on the surface of a material

Front 79

2. How is a static charge generated?

Back 79

2. By the motion of one substance relative to another substance. As they’re rubbed together and separated, one

substance gains electrons and the other loses electrons. This results in the buildup of electron charges on the

surfaces of the substances which are equal but opposite in polarity.

Front 80

3. Does static electricity occur more easily in dry or humid air?

Back 80

3. Dry.

Front 81

4. How much static charge could be produced by simply walking across a vinyl floor during a period of

low humidity?

Back 81

4. As much as 12,000 volts

Front 82

5. List the seven types of ESD sensitive devices

Back 82

5. Any seven of the following:

(1) MOSFETs.

(2) PROMs.

(3) ROMs.

(4) RAMs.

(5) CMOS.

(6) Discrete semiconductors.

(7) Film resistors.

(8) Resistor chips.

(9) Film devices.

(10) Piezoelectric crystals.

Front 83

214. Electrostatic discharge protection procedures

1. Why are ESD failures often difficult to identify?

Back 83

1. Since ESD could cause only partial failure or an intermittent failure, an LRU that has been exposed to ESD may

check out good on the repair bench, but fail on the aircraft during flight.

Front 84

2. List the precautions you should take to protect aircraft components from ESD damage while working

on the flight line.

Back 84

2. (1) Cover exposed terminals and cable connectors with protective caps or covers.

(2) Never transport an LRU without the proper connector cover.

(3) Never apply pressure sensitive tape directly to connector pins of the LRU or aircraft wiring.

(4) Always ensure that the aircraft is grounded before you remove or install an LRU.

(5) Touch the LRU case with your hand before disconnecting the cable.

(6) Touch the outer shells of mating connectors together before connecting the cable.

(7) Never remove or install an LRU with power applied to the aircraft

Front 85

3. List the four main parts of an ESD protected area.

Back 85

3. (1) Grounded workbench.

(2) Personnel wrist strap.

(3) Grounded floor mat.

(4) Grounded tools and equipment

Front 86

4. What should the series resistance value be for the grounding cable on a grounded workbench?

Back 86

4. At least 250,000 Ohms.

Front 87

5. What safety feature should be incorporated into the personnel wrist strap?

Back 87

5. A quick-release mechanism

Front 88

6. What is a possible danger involved with the use of ionizers?

Back 88

6. Possible radiation hazard

Front 89

7. What types of protective clothing are available?

Back 89

7. ESD protective smocks, gloves, and aprons

Front 90

215. Types of wires and cable

1. Describe the construction features of insulated wire.

Back 90

1. A metal conductor covered with a dielectric or insulation material.

Front 91

2. What’s the purpose of having stranded conductors in wire used on aircraft?

Back 91

2. Allows for flexibility

Front 92

3. Describe the construction features of shielded cable

Back 92

3. Has a metallic braid over the insulation to provide a barrier against electromagnetic interference

Front 93

4. Describe the construction features of coaxial cable.

Back 93

4. Consists of an inner (center) conductor separated by an insulation dielectric

Front 94

7. Describe the protective layers of an EMP cable

Back 94

7. There are three outer protective layers, consisting of a braided overall shield, a laminated copper foil-mylarcopper

foil tape wrap, and a second braided overall shield.

Front 95

8. What part of an EMP cable can be repaired in the field?

Back 95

8. The first two layers and a jack or connector.

Front 96

216. Characteristics of aircraft electrical and radio frequency connectors

1. What are the two parts of an electrical connector? How is the electrical connector coupled?

Back 96

1. A plug assembly and a receptacle assembly. Coupled by means of a coupling device which is part of the plug

assembly.

Front 97

2. What part of an electrical connector is usually the fixed part?

Back 97

2. The receptacle.

Front 98

3. Which part of a connector/circuit should be the “hot” side?

Back 98

3. The socket (female) side.

Front 99

4. How are pin-and-socket contacts connected to the wires?

Back 99

4. Either by soldering or crimping

Front 100

5. What problems can occur if you don’t adhere to the design dimensions of a RF connector?

Back 100

5. Added RF power losses and/or radiation interference.

Front 101

217. Introduction to fiber optic cable

1. What’s a major factor to consider when using fiber optic cables in place of conventional wire cables?

Back 101

1. The elasticity of the glass fibers

Front 102

2. Twisting a fiber optic cable during installation can have what effect?

Back 102

2. It can cause disturbances in lay uniformity, resulting in reduced power transmission

Front 103

3. Why is it important to control the stress and forces exerted on a fiber optic cable?

Back 103

3. Because of the small diameter of the cables.

Front 104

4. In what areas does the military use fiber optic cable?

Back 104

4. Almost anywhere copper wire is used including fixed facilities, and tactical applications in aircraft, ships,

vehicles, and communications/radio shelters.

Front 105

5. What’s the key advantage of fiber optics in a tactical computer application?

Back 105

5. Its immunity to EMI.

Front 106

6. What are the advantages of fiber optics?

Back 106

6. Wide bandwidth, low attenuation, resistance to electromagnetic interference, small size, light weight, increased

safety, increased security, and faster speed.

Front 107

7. What’s the security advantage of fiber optics?

Back 107

7. It’s nearly impossible to tap a fiber optic cable.

Front 108

8. What’s the primary use for fiber optic cable?

Back 108

8. As a transmission link, connecting the two electric circuits of a transmitter and receiver.

Front 109

9. What’s the active component in a fiber optic communication system?

Back 109

9. The source.

Front 110

10. What are the two types of light sources used in a fiber optic system?

Back 110

10. LEDs and ILDs.

Front 111

11. What source is easiest to use?

Back 111

11. LEDs.

Front 112

12. How can you tell if a fiber optic system is energized?

Back 112

12. If power is applied to the system, you must assume the fiber is energized. You can’t see whether a source is

energized or not. Never look directly into a fiber unless you’re positive that it isn’t energized.

Front 113

13. What part of a fiber optic system converts the optical energy back to electrical energy?

Back 113

13. The detector.

Front 114

14. What two types of detectors are used in fiber optic systems?

Back 114

14. PIN and APD.

Front 115

15. What are the three parts of a fiber optic cable?

Back 115

15. The core, cladding, and buffer

Front 116

218. Soldering fundamentals

1. Why are exact dimensions necessary when stripping wire with wire strippers?

Back 116

1. To ensure proper connection.

Front 117

2. Why is rosin solder used for electrical soldering versus acid core?

Back 117

2. Rosin doesn’t produce the corrosive effects that are noted when acid is used as a flux.

Front 118

3. Explain a high-resistance solder connection.

Back 118

3. Solder composed of equal parts of tin and lead has an electrical conductivity that’s much lower than that of

copper wire, therefore. Make every joint to be soldered mechanically secure to prevent solder from separating

the conductors and causing resistance between them.

Front 119

4. Describe why flux is so important in the soldering process

Back 119

4. It prevents the oxygen in the air from combining with the metal (oxidation) which, in turn, prevents the solder

from fusing properly.

Front 120

219. Precautions, care, and procedures for using a soldering iron

1. Explain the purpose of keeping the soldering iron temperature correct.

Back 120

1. An iron that’s too hot won’t allow solder to adhere to it.

Front 121

2. What could be the consequences of using too much solder?

Back 121

2. Dripping solder could serious burns or damage equipment.

Front 122

3. Describe the first step of soldering joints.

Back 122

3. The first step is tinning. The item is heated allowing solder to melt and form a thin layer necessary to make a

solid solder joint.

Front 123

220. Types and use of solderless connectors

1. What’s the purpose of the terminal lug?

Back 123

1. To permit easy and efficient connection to and disconnecting from electrical equipment.

Front 124

2. Describe the use of the splice

Back 124

2. Joins two electrical wires into a permanent, continuous wire run

Front 125

3. Why do connector plugs make connections more reliable?

Back 125

3. Removable pins are crimped and inserted into a connector where more than one wire can be connected or

disconnected at one time.

Front 126

221. Proper use, care, and precautions of solderless connector tools

1. Explain the purposes of crimping tools.

Back 126

1. To ensure a good mechanical connection and to ensure that the crimp is not too loose or tight.

Front 127

2. Why is it necessary to properly crimp a connector?

Back 127

2. Because a crimp that’s too tight either breaks the connector or makes it fragile so that it will break under

vibration; a crimp that’s loose will cause the wire to have a poor connection.

Front 128

3. How can you ensure that you’re using the correct insertion/extraction tool?

Back 128

3. By looking in the applicable aircraft wiring tech order or TO 1-1A-14 to see which tool is used with which type

of connector part number.

Front 129

222. Wiring maintenance heating tools

1. What are the user’s responsibilities prior to using heating tools in a potentially explosive

environment?

Back 129

1. To determine the suitability for use in a particular environment and to operate the tool in accordance with local

policies and directives and the correct operations manual and warnings. Failure to do so could result in fire

and/or explosion.

Front 130

2. When using a heat tool, what determines the correct air temperature and pressure?

Back 130

2. The application instructions for the particular product you’re installing.

Front 131

223. Cable and wire repair

1. What is considered to be EMP cable repairable damage?

Back 131

1. Damage to cable jacket, to outer braided shield or underlying foil wrap, and broken wires at the connector.

Front 132

2. What is the criterion for flight line repair of the outer cable shield?

Back 132

2. Minor shield damage that doesn’t affect more that 25 percent of the outer shield circumference.

Front 133

3. Describe how to reapply copper shielding tape.

Back 133

3. Apply with a 20 to 40 percent overlap over the rewrapped shielding tape so the applied wrap covers at least 11/2

to 2 straight wraps of 1/2-inch wide pressure sensitive polyester tape.

Front 134

4. Describe the first step of wire repair.

Back 134

4. Check TO 1-1A-14 to ensure you have the proper materials for the job.

Front 135

5. What precaution must you take before applying heat shrink on a repair job?

Back 135

5. You must heed tech data warnings concerning use of heating tools on fueled aircraft.

Front 136

224. Wire bundling

1. Why is wire bundling important to proper maintenance?

Back 136

1. Provides ease of installation, maintenance, and inspection; provides strain relief.

Front 137

2. What is the recommended type of material for tying and bundling?

Back 137

2. Narrow flat type.

Front 138

3. Where is continuous lacing used?

Back 138

3. Only on those wire groups or bundles that are to be installed in panels or junction boxes.

Front 139

4. What are the spacing requirements for tying wire groups or bundles?

Back 139

4. You need to tie all wire groups or bundles where supports are more than 12 inches apart and all ties need to be

spaced 12 inches or less apart.

Front 140

5. What is the warning that you must heed when using cable straps?

Back 140

5. The strap must be cut flush with the boss surface in order to eliminate painful cuts and scratches from

protruding strap ends.