Textbook (Emilio's Quizzes) Flashcards
(155 cards)
1
Q
The Federal Aviation Act of 1958 repealed the Civil Aeronautics Act and created what?
A
The Federal Aviation Agency
2
Q
What year was the Federal Aviation Agency brought into the Department of Transportation to be renamed? What was it renamed to?
A
1967
Federal Aviation Administration (FAA)
3
Q
What is the responsibility of the Federal Aviation Administration (FAA) what what are it’s primary regulatory tool?
A
The FAA is responsible for regulating and promoting civil aviation in the United States and it’s primary regulatory tools are the Federal Aviation Regulations (FARs).
4
Q
What is FAR Part 21?
A
Certification Procedures for Products and Parts
FAR Part 21 lists the requirements for establishing and maintaining the certification of aircraft and components.
5
Q
When an aircraft is manufactured, an inspector determines if it conforms to the model’s what?
A
Type Certification
6
Q
What is a Type Certification?
A
Certificate that list all pertinent information on an aircraft or accessory design.
7
Q
When an aircraft is in conformity and meets the standard for service, what is it issued?
A
Airworthiness Certification.
8
Q
What is FAR Part 23?
A
Airworthiness Standards: Normal, Utility, Acrobatic, and Commuter Category Airplanes.
FAR Part 23 describes in detail the performance characteristics various aircraft must demonstrate to be airworthy. It specifies requirements for every component and system installed on an aircraft, often down to the smallest detail.
9
Q
What is FAR Part 39?
A
Airworthiness Directives
10
Q
What is a Airworthiness Directives?
A
When an unsafe condition exists with an aircraft engine, propeller, or accessory, the FAA issues an Airworthiness Directives (AD) to notify and to describe the appropriate corrective action.
11
Q
What is FAR Part 43?
A
Maintenance, Preventive Maintenance, Rebuilding and Alterations.
Part 43 outlines the fundamental standards for aircraft inspection, maintenance, and repair, as well as all record keeping requirements.
12
Q
What is FAR Part 65?
A
Certification: Airmen other than Flight Crewmembers
Part 65 discusses the certification requirements as well as the privileges and limitations for aviation technicians.
13
Q
What is FAR Part 91?
A
General Operating and Flight Rules
FAR Part 91 Subpart E contains the regulations governing the maintenance, preventive maintenance, and alteration of U.S registered aircraft. Unlike Part 43, Subpart E of part 91 outlines the inspection that must be performed on all aircraft.
14
Q
An operation that restores an item to a condition of practical operation or to original condition is called what?
A
Repair
15
Q
Any change in the configuation or design of an aircraft is called what?
A
Alteration
16
Q
A operation that might appreciably affect weight, balance, structural strength, performance, powerplant operation, flight characteristics, or other airworthiness factors is called what?
A
Major Repair
17
Q
An alteration not listed is the product’s specification and that might affect the product’s performance in a similar fashion to a major repair is called what?
A
Major Alteration
18
Q
A list of examples for major repairs and alteration, engines, propellers, and appliances can be found where?
A
Appendix A of FAR Part 43
19
Q
A complete listing of those items that are classified as preventive maintenance can be found where?
A
Appendix A of FAR Part 43
20
Q
A listing of performance criteria for performance inspections and inspection check-lists can be found where?
A
FAR 43 Appendix D
21
Q
Annusl inspections are based on what?
A
12 calender months
22
Q
Who is authorized to do an annual inspection?
A
An Inspecion Authorization (IA)
23
Q
Who is able to perform an 100 hour inspection?
A
A&P Technician
or
Inspection Authorization (IA)
24
Q
What is the exception for an airplane for fly after it is due for it’s 100 hour inspection?
A
A maximum of 10 hours is given after the 100 hours to permit the aircraft to fly to a place where the inspection can be accomplished.
25
What is a Type Certification Data Sheet?
A data sheet that contains the informaion necessary for the proper maintenance and inspection of an aircraft or its associated equipment. Information contained in a TCDS is considered *approved data* for use on a 337 Form.
26
Information regarding minumum fuel grade for the approved engine and control surface movements in degrees can be found where?
Type Certification Data Sheet (TCDS)
27
A Federal Aviation Administrator or any person to whom he has delegated his authority in a matter concerned is called what?
Administrator
28
A device that is used or intended to be used for flight in the air is called what?
Aircraft
29
The fuselage, booms, nacelles, cowlings, fairings, airfoil surfaces (including rotors but not excluding propellers and rotating airfoils of engines), and landing gear of an aircraft and their accessories and controls is together called what?
Airframe
30
An engine-driven fixed-wixed aircraft heavier than air, that is supported in flight by the dynamic reaction of the air against the wing is caled what?
Airplane
31
Any instrument, mechanism, equipment, part, apparatus, or accessory, including communications equipment, that is used or intended to be used in operating or controlling an aircraft in flight, is installed in or attached to the aircraft, and is not part of an airframe, engine or propeller is called what?
Appliance
32
Unless used with reference to another person, what meas approved by the FAA or any person to whom the FAA has delegated its authority in the matter concerned, or approved under under the provision of a bilateral agreement between the United States and a foreign country or jurisdiction.
Approved
33
An aircraft other than a public aircraft is called what?
Civil Aircraft
34
A person assigned to perform duty in an aircraft during flight time is called what?
Crewmember
35
1) Pilot time that commences when an aircraft moves under its own power for the purpose of flight and ends when the aircraft comes to rest after landing; or
2) For a glider without self-launch capability, pilot time that commences when the glider is towed for the purpose of flight and ends when the glider comes to a rest after landing.
What is this called?
Flight Time
36
Inspection, overhaul, repair, preservation, and the replacement of parts, but excludes preventive maintenance is called what?
Maintenence
37
Simple or minor preservation operations and the replacement of small standard parts not involving complex assembly operations is called what?
Preventive Maintenance
38
With respect to maintenance time records, this means the time from the moment an aircraft leaves the surface of the earth until it touches it at the next point of landing. What is this called?
Time in Service
39
Manufacturer's maintenance manual information is considered what type of information by the FAA?
Approved Data
40
What type of information and drawings does overhaul manuals contain?
Information on the repair and rebuilding of components that can be removed from an aircraft.
These manuals contain muliple **illustrations** showing how individual components are assembled as well as list individual part numbers.
41
What type of information and drawings does illustrated parts catalog contain? Is it approved data?
Parts catalog show the location and part numbers of items installed on an aircraft. They contain detailed **exploded view** of all areas of an aircraft to assist the technician in locating parts.
They are not considered acceptable data for maintenance and repair by the FAA
42
What type of information and drawings does wiring manuals contain?
Aircraft electrical system and their components are illustrated in individual wiring manuals. Wiring manuals contain **schematic diagrams** to aid in electrical system troubleshooting.
43
What type of information and drawings does structural repair manuals contain? Is it approved data?
For repair of serious damage, structural repair manual are used. These manuals contain detailed information for repair of an aircraft's primary and secondary structure.
The repairs described in the structual repair manual are developed by the manufactuer's engineering staff and are usually considered approved data by the FAA.
44
What FAA publication is used to notify aircraft owners of unsafe conditions?
Airworthiness Directives
45
How often are Airworthiness Directives issued by the FAA?
On a biweekly schedule.
46
According to FAR 91.417, who is primarily responsible for maintaining an aircraft's required maintenance records?
The aircraft's owner
47
As a aircraft technician, any work you do on a aircraft needs to be what?
Documented
48
Major repairs and alterations to aircraft are recorded on what type of form?
FAA form 337
49
A copy of a completed FAA Form 337 must be provided to the local FAA office within\_\_\_\_\_\_hours after approval for return to service.
48
50
What can an A&P mechanic do as a mechanic?
Name 5 things
1) Minor repair and alterations
* Airframe
* powerplants
* Propellers
* Components
2) Approve minor repair and alterations for return to service
3) Major repair and alterations
* Airframe
* Powerplants
* Components
4) Perform 100 hour inspection
* Airframe
* Powerplants
* Propellers
* Accessories
* Instruments
5) Approve 100 hour inspection for return to service
51
What can an A&P mechanic NOT do as a mechanic?
Name 5 things
1) Cannot do Major repair or alerations on
* Propellers
2) Cannot approve a major repair or alteration for return to service.
3) Cannot do any repair or alteration to instruments.
4) Cannot delegate his inspection duties in a 100 hour inspection
5) Cannot perform annual inspections
52
The term that describes weight of the standard aircraft including any optional or special equipment, fixed ballast, unusable fuel, and full operating fluids including oil, hydraulic fluid, and other fluids required for normal operation of aircraft systems except potable water, lavatory precharge water, and water intended for injection in the engines is called what?
Basic empty weight
53
Aircraft certified prior to \_\_\_\_\_\_\_\_\_, might use the term \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_, which is similar to basic empty weight except that it does not include full engine oil. For these aircraft, the licenced empty weight includes only the weight of undrainable oil.
March 1, 1978
Licenensed empty weight
54
The weight of an aircraft without optional equipment, and is obtained from the aircraft manufacturers is called what?
Standard Empty weight
55
Standard weights are used for computing the weight of fuel, oil, crew, and baggage. For general weight and balance purpose, the following weights are considered standard:
## Footnote
Avgas..................................\_\_\_\_\_pounds per gallon
Turbine fuel.......................\_\_\_\_\_pounds per gallon
Lubricating oil...................\_\_\_\_\_pounds per gallon
Water..................................\_\_\_\_\_pounds per gallon
Crew & Passengers......\_\_\_\_\_\_ for utility/aerobatic aircraft
Avgas.................................. 6 pounds per gallon
Turbine fuel....................... 6.7 pounds per gallon
Lubricating oil...................7.5 pounds per gallon
Water..................................8.35 pounds per gallon
Crew & Passengers...... 190 pounds for utility/aerobatic aircraft
56
What refers to the weight of the flight crew, passengers, and any cargo or baggage?
Payload
57
The difference between the maximum takeoff weight and the basic empty weight which includes payload, usable fuel, and full operating fluids is called what?
Useful load
58
The fuel that is available for flight is called what?
Usable fuel
59
The operational weight of the aircraft including the payload but excluding the fuel load is called what?
Zero fuel weight
60
Maximum weight approved for aircraft ground operations is called what?
Maximum ramp weight
61
Basic Empty Weight
_+ \_\_\_\_\_\_\_\__
= Zero Fuel Weight
_+ \_\_\_\__
= Ramp Weight
_- _
= Takeoff Weight
_- \_\__
= Landing Weight
Basic Empty Weight
_+ Payload\_\_\_\_\_\_\_\__
= Zero Fuel Weight
_+Usable Fuel\_\_\_\_\__
= Ramp Weight
_- Fuel Used for Start, Taxi, and Engine Runup_
= Takeoff Weight
_- Fuel Used During Flight\_\__
= Landing Weight
62
.............?.........
_+ Payload_\_\_\_\_\_\_\_\_
= ...........?.................
_+Usable Fuel_\_\_\_\_\_
= ..............?................
_- Fuel Used for Start, Taxi, and Engine Runup_
= ...........?.............
_- Fuel Used During Flight\_\__
= ................?.......................
Basic Empty Weight
_+ Payload\_\_\_\_\_\_\_\__
= Zero Fuel Weight
_+Usable Fuel\_\_\_\_\__
= Ramp Weight
_- Fuel Used for Start, Taxi, and Engine Runup_
= Takeoff Weight
_- Fuel Used During Flight\_\__
= Landing Weight
63
With an forward CG limit, it will be too nose heavy. Although this tends to make an aircraft seem stable, adverse side affects include longer\_\_\_\_\_\_\_\_\_\_\_\_\_ and a higher\_\_\_\_\_\_\_\_.
With an forward CG limit, it will be too nose heavy. Although this tends to make an aircraft seem stable, adverse side affects include longer takeoff distance and a higher stalling speeds.
64
With an aft CG, the aircraft becomes tail heavy and very unstable in \_\_\_\_\_\_\_\_\_, regardless of speed. Furthermore, when the CG is beyond the aft limit, the stabilator may be ineffective for\_\_\_\_\_\_\_\_\_\_\_\_\_
With an aft CG, the aircraft becomes tail heavy and very unstable in pitch, regardless of speed. Furthermore, when the CG is beyond the aft limit, the stabilator may be ineffective for stall or spin recovery.
65
The imaginary vertical plane from which all horizontal measurements are taken with the aircraft in a level flight attitude is called what?
Datum Line
66
When an object's weight is multiplied by it's arm, the result is known as what? What is it expressed in?
Moment
Pound-feet or pound-meters
67
The distance of an item from the datum is called what?
Arm
68
What type of scales are used for measuring large planes vs. smaller planes
Platform scales - smaller planes
Load cells - larger planes
69
The CG location in a transport aircraft is given in terms of percent of the what?
Mean Aerodynamic Chord
| (%MAC)
70
The Leading Edge and Trailing Edge of the Mac is referred as what?
LEMAC
TEMAC
71
A weight in the aircraft to bring the CG into its desired range is called what?
Ballast
72
How do you convert oil's quantiy from quarts to pounds?
Divide quart amount by 4, then multiply by 7.5. The answer is expressed in Pounds per Gallon.
73
If weight is needed to move the CG to a desired location, what formula do you use?
Ballast Formula
## Footnote
Ballast =
Aircraft Weight x Change in C.G Desired ÷ Ballast Arm - Arm of Desired C.G
**Change of C.G Desired** - Expressed in inches forward or backward from the other C.G
**Ballast Arm** - Distance from datum to where you will place the weight
**Arm of desired C.G** - Distance from datum to where you will place the weight
74
If you need to shift the weight around to put the C.G within limits, what formula do you use?
Weight Shift Formula
Weight Shifted ÷ Total Weight = C.G change required ÷ Distance weight is shifted
**Change of C.G Desired** - Expressed in inches forward or backward from the other C.G
**Distance weight is shifted** - The difference between the two stations from where the weight will be shifted.
**Total weight** - the total weight of the aircraft.
75
What is a METO, when is it used, what is it's formula, and where can it be found?
METO - Maximum except take-off horsepower. It's rating is found in the Type Certifacation Data Sheet. It is used when trying to find the minumum fuel for a CG check.
Formula
Minimum Fuel = METO ÷ 2
76
As a formula, the solution to solve for the percent of
MAC would be what?
% MAC = CG − LEMAC ÷ MAC × 100
77
In regards to exterior cleaning, the use of nonapproved or ordinary commercial compounds can result in a condition known as what?
Hydrogen Embrittlement
Hydrogen embrittlement results when a chemical reaction produces hydrogen gas that is absorbed into a metal. This process subsequently reduces a metal's ductility and allows the formation of cracks and stress corrosion
78
The type of materials to be used in cleaning depends on the nature of the elements that need to be removed. When removing oil, grease, or soft preservative compounds, what type of dry-cleaning solvent is used? What are the 2 common types?
**Naphta**
* **Aliphatic Naphta** - hydrocarbon solvent that dissolves oil and grease but does not harm rubber or acrylic components. This is frequently used to wipe down cleaned surfaces before painting.
* **Aromatic naphtha** - attacks rubber and acrylic compounds.
79
When a metal such as aluminum is exposed to a gas containing oxygen, a chemical reaction takes place on the surface between the metal and the gas. Two aluminum atoms join three oxygen atoms to form aluminum oxide (AL2O3). If the metal is iron or steel, two atoms of ion join three atoms of oxygen to form iron oxide, or rust (Fe2O3).
What is this type of corrosion called?
Oxidation aka "dry" corrosion
The difference between iron oxide and aluminum oxide is that the film of aluminum oxide is unbroken and, therefore, once it has formed, further reaction with oxygen slows dramatically. Iron oxide, on the other hand, forms a porous, interrupted film. Since the film is not air tight, the metal continues to react with oxygen in the air until the metal is completely eaten away.
80
A type of corrosion often recognized as powdery deposits of salt or small blisters along the surface of a metal is called what?
Uniform Surface Corrosion
81
What type of corrosion is formed when uniform surface corrosion is left untreated and localized clumps of powdery salts is formed on the metal?
Pitting Corrosion
82
A type of corrosion that is formed when two dissimilar metals make electrical contact with the presence of an electrolyte is called what?
Galvanic Corrosion
83
What are the three general types of Concentration Cell Corrosion?
1. **Oxygen Concentration Cell Corrosion** - forms in the areas where there is a deficiency of oxygen *between* air tight lap joints
2. **Metal Ion Concentration Cell Corrosion** - forms in the open at the *edge* of a lap joint
3. **Active-Passive Cell Cell Corrosion**
84
A special form of oxygen concentration cell corrosion (crevice corrosion) recognized by its fine threadlike lines or puffines under the paint film and first noticed around rivet heads along the lap joints of skins is called what?
Filiform Corrosion
Filiform corrosion often results when the washer primer used on the metal has not been properly cured. A wash primer is a two0part metal preperation material in which phosphoric acid converts the surface of the metal into a phosphate film that protects the metal from corrosion, and provides an excellent bond for paint. This conversion process relies on moisture in the air and, if there is not enough moisture to convert all of the acid, some acis remains on the metal. If a dense polyurethane finish is then applied, the acid becomes trapped and reacts with the aluminum alloy to form corrosion.
85
After a heat treatment process, the alloy must be quenched promptly after it is removed from the heat bath. If quenching is delayed for even a few seconds, particles of the alloying agent precipitate out of the metal matrix and can become quite large. If quenching is delayed too long, these metal grains can reach a size that produces areas of dissimilar metals large enough to form effective cathodes and anodes so that \_\_\_\_\_\_\_\_\_corrosion can form.
Intergranular Corrosion
86
An extreme case of intergranular corrosion which occurs along the grain boundaries and causes the material to seperate, or delaminate is called what?
Exfoliation Corrosion
87
\_\_\_\_\_\_\_corrosion occurs when metal is subjected to tensile stress in the presence of a corrosive envrioment. Cracks caused by this corrosion grow rapidly as the corrosive attack concentrates at the end of the crack rather than along the side?
Stress Corrosion
88
When two surfaces fit tightly together but can move relative to one another, corrosion occurs. This type of corrosion is the result of the abrasive wear caused by the two surfaces rubbing against each other. What is this corrosion called?
Fretting Corrosion
89
Corrosion is an __________ action in which a metal is changed into a chemical salt.
Electrochemical
90
The four basic requirements for the formation of corrosion in a material is what?
1. Anode
2. Cathode
3. Electrolyte
4. Electrical contact between the anode & cathode.
91
What is used to neutralize Lead-Acid & Nickel-Cadmium batteries
Lead Acid - Bicarbonate Soda
Nickel-Cadmium - Boric Acid
92
What is used to determined that a battery area is completely neutralized?
Litmus Paper
93
What is Anodizing?
The process of applying an oxide film that protects the alloy from further corrosion by an *electrolytic* process
94
What is Alodizing?
The process of applying an oxide film that protects the alloy from further corrosion by an *chemical* process
95
What is sacrificial corrosion?
Using a cadmium plating to protect steel parts from corrosion.
96
What type of brushes are used to remove corrosion?
Stiff nonmetallic bristle brushes or nylon scrubbers
97
Some materials have an atomic structure that easily permits the movement of electrons. The materials are referred to as __________ .Materials which oppose the movement of electrons are called\_\_\_\_\_\_\_\_\_\_ .
Conductor
Insulator
98
The basic unit of electrical quanity and is equivalent to 6.28 billion billion electrons and typically written as 6.28 x 1018 is what? What is it's symbol?
coulomb
Its symbol is "Q"
99
What is an ampre (one amp) ? What is it's symbol?
When one coulomb of electrons flows past a point in one second.
It's symbol is "I"
100
What is an Ohm? What is it's symbol?
The standard unit of resistance, or opposition to current flow, and is represented by an "Ω".
One ohm is the resistance through which a force of one volt results in a flow of one ampere.
101
What is an electromotive force or EMF? What is this force measured in and what is it's symbol?
EMF is the force that causes electrons to flow.
This force is measured in **volts.** One volt represents the amount of force required to cause one amp of flow *through* one ohm of resistance.
The symbol used to represent the volt is "E or V"
102
What is a watt? What is it's symbol?
The standard unit of measure for electrical power.
It's symbol is "P"
103
What are the two basic types of electricity and what is the difference?
**Current electricity** - electrons move through a circuit and perform work through the magnetic field created by their movement, or by the heat generated when forced through a resistance.
**Static electricity** - non-moving electrons and serve little useful purpose.
104
When an airplane flies through the air, friction causes a static charge to build on the aircraft's surface. To help prevent an excessive charge from buulding, many aircraft utilize\_\_\_\_\_\_\_to discharge the electricity into the air.
Static wicks
105
What is the photo below? What is it used for and what is it's maximum permissible resistance?
Bonding strap - provides a conductive path for static electricity to move from aircraft's control surfaces to the airframe for discharging.
The maximum permissible resistance of a bonding strap is .**003 ohms**.
106
\_\_\_\_\_\_\_\_\_\_\_ is a basic statement which says the current that flows in a circuit is directly proportional to the voltage (force) that causes it, and inversely proportional to the resistance (oposition) in the circuit.
What is the formula for the relationship between volts, amps, and resistance?
What is the formula for the relationship between power, current, and voltage?
Ohm's Law
Relationship between volts, amps, and resistance
* Volt = Amps x Resistance (E = I x R)
Relationship between power, current, and voltage
* Power = Amps x Volts (P = I x E)
107
What is the difference between SPST, SPDT, DPST, and DPDT switches?
Which one is used to control both the battery and generator circuit so they both can turn ON and OFF at the same time?
**Single-pole, Single-throw (SPST)** - Used on single wire circuits
**Single-pole, Double-throw (SPDT)** - Used on two single wire circuits but allows only one circuit to be energized at a time.
**Double-pole, Single-throw (DPST)** - Used to control two circuits simultaneously (OFF/ON together) and may be of different voltages and from seperate sources. *This is used to control both the battery and generator circuit so they both can turn ON and OFF at the same time*
**Double-pole, Double-throw (DPDT)** - Used to control four circuits, permitting only two circuits to be energized at one time.
108
What is a precision switch?
A switch that is activated by the movement of some mechanism. It is usually important that this switch is activated when the mechanism moves and reaches a very definite and specific location
109
Charged atoms are called ions. If an atom possesses an excess of electrons, it is said to be negatively charged, and is called a \_\_\_\_\_\_\_. On the other hand, an atom with excess protons is called a \_\_\_\_\_\_\_\_.
Charged atoms are called ions. If an atom possesses an excess of electrons, it is said to be negatively charged, and is called a **negative ion**. On the other hand, an atom with excess protons is called a **positive ion**.
110
What simple rule is used to determine the direction the lines of flux travel through conductors?
Left Hand Rule
(Knuckles Down Counter-Clockwwise)
If you grasp the conductor in your left hand with your thumb pointing in the direction of electron flow, your fingers encircle the conductor in the direction of the lines of flux travel.
111
What simple rule is used to determine which end of an electromagnet is north and which is south?
Left-Hand Rule for Coils
(Knuckles Up clock-wise)
This rule states that if you grasp a coil with your left hand so your fingers wrap around the coil in the direction of electron flow, your thumb points to the coil's north pole.
112
What are the two most common switches used to control the flow of electrons in aircrafts?
Enclosed toggle switch
Rocker switch
113
What type of switches are used when it is necessary to select any of a large number of circuit conditions.
Wafer Switch
114
An electrical switch that is operated from a remote location is called what?
What are the two general types?
**Relay Switch**
There are two general types of relays used in the aviation industry; those having fixed cores, and those with movable cores. Both use a coil of wire, or *solenoid.*
1. **Fixed-Core Electromagnet Switch** - the core remains stationary at all times, however, once current flows through the coil, the magnetic force produced opens or closes a set of contacts to complete another circuit.
2. **Movable-Core Electromagnetic Switch** - The core of the electromagnet is typically held out from the center of the coil by a spring, however, once current flows through the coil, a strong magnetic field is produced that overcomes the spring and pulls the core into the center of the coil. When this occurs, a set of contacts attached to the core are pulled down to complete another circuit.
115
What is the difference between overloading and a short?
**Overloading** - overloading a circuit results from connecting loads that are too large for the wiring.
A **Short** - Part of a circuit comes in direct contact with the return side of the circuit. When a short occurs, a path for current flow with little or no resistance is established. This results in large amounts of current flow and conductor heating.
116
A ______ is made of a low-melting-point alloy enclosed in a glass tube and installed as part of a circuit. When current flow becomes excessive, the metal alloy melts and open the circuit to prevent wire damage.
Fuse
117
Like fuses, \_\_\_\_\_\_\_\_automatically open a circuit if current flow becomes excessive. However, once the circuit cools, this item can be easily reset by moving the operational control.
Circuit Breakers
118
What does it mean when it is said that aircraft circuit breakers are of a "trip-free type" ?
It means that once the breaker opens, the circuit remains open until the circuit cools regardless of the position of the operating control. With this type of breaker, it is impossible to hold the circuit if an actual fault exits.
119
What are the **two basic principles** that curcuit breakers operate on?
What are the three types?
**Thermal Breakers** - opens a circuit when excess current heats an element in the breaker causing the contact to open.
**Magnetic Breakers** - uses the magnetic field caused by the current in the circuit to open the contacts
Three basic types used in aircrafts
1. Push/Pull
2. Push-to-Reset
3. Toggle Type
120
What is used in electrical circuits to control the amount of current flow?
How is this done?
Resistors
They do this by converting some of the electrical energy that flows through the aircraft into heat. The resistors used in aircraft are generally cassified as *fixed* or *variable*
121
A type of variable resistor that controls resistance vary the amount of current flow in a circuit is called what?
Rheostats
122
A type of variable resistor that changes the amount of voltage in a circuit and are often used as voltage dividers is called what?
Potentiometer
123
Voltmeters, ammeters, and ohmmeters are used to analyze values in electrical circuits. Some basic rules should be followed in thier use to prevent injury to the technician or damage to the meters and circuit components. Explain proper procedures for each of the following:
Measuring Voltage
Measuring Amperage
Measuring Resistance
1. Voltage is always measured across a component. In other words, the probes of the volt-meter go across, or parallel to, the component being measured
2. Amperage is measured by placing the meter in series with a component. The technician must be sure the ammeter is able to handle the current in the circuit being measured.
3. Resistance is measured with power off the circuit. Individual components mest be isolated from the circuit if their resistance are to be checked.
124
Name the three components needed to complete the circuit.
Source
Load
Conductors
125
The resistance of a conductor is affected by what three factors.
Physical Characteristics
Dimensions
Temperature
126
When electrons flow in a conductor, they cause an \_\_\_\_\_\_\_to surround the conductor.
Magnetic Field
127
Each unit of electrical measurement may be expressed using a single letter. What letters are used for the expressions below?
Voltage
Current
Resistance
Power
Voltage - E
Current - I
Resistance - R
Power - P
128
The AC wave form produced by a rotary generator is called?
Sine Wave
129
One complete sequence of voltage or current change from zero, through a positive peak, back to zero, through a negative peak, and back to zero again is called what?
A Cycle
130
One-half of an AC cycle in which the voltage or current rises or falls from zero to a peak and back to zero is called what?
Alteration
131
The time required for one cycle of events to occur is called what?
Period
period of the alternating current or voltage
132
The frequency of AC is the number of \_\_\_\_\_\_\_\_\_\_\_. Frequency is expressed in\_\_\_\_\_\_ with one hertz equal to \_\_\_\_\_\_per second.
The frequency of AC is the number of **cycles completed in one second**. Frequency is expressed in **hertz (Hz**) with one hertz equal to **one cycle** per second.
133
The maximum value of voltage or current in either positive or the negative direction of a sine wave is called what?
Peak Value
134
The difference between the positive and the negative sine wave peak values is called what?
Peak-to-peak value
135
A sine wave's \_\_\_\_\_\_\_\_\_\_is found by multiplying its peak value by the sine of the angle through which the loop rotates beyond its zero-voltage position.
Instantaneous value
136
If all of the instantaneous values of current or voltage in one alteration of a sine wave are averaged together, they will have a value of ______ and is referred to as an \_\_\_\_\_\_\_\_\_\_\_.
If all of the instantaneous values of current or voltage in one alteration of a sine wave are averaged together, they will have a value of **0.637** and is referred to as an **average value**.
137
The AC value that produces the same amount of heat as a corresponding amount of DC is called what?
Effective value
138
To determine the effective value, square all of of the instantaneous values in one alteration, find the average of these squared values, and calculate the square root of this average. The effective value is sometimes referred to as\_\_\_\_\_\_\_\_\_and is \_\_\_\_\_\_of the peak value.
To determine the effective value, square all of of the instantaneous values in one alteration, find the average of these squared values, and calculate the square root of this average. The effective value is sometimes referred to as root mean square (RMS) and is 0.707 of the peak value.
139
The amount of shift between the voltage and the current is called what?
Phase angle
140
In the study of direct current, electrical power is the product of voltage and current and is measured in watts. However, with alternating current, the values for both voltage and current are given in effective values. The product of these effective values is called the _____ and is expressed in \_\_\_\_\_rather than watts.
In the study of direct current, electrical power is the product of voltage and current and is measured in watts. However, with alternating current, the values for both voltage and current are given in effective values. The product of these effective values is called the **apparent power** and is expressed in **volt-amps** rather than watts.
141
The actual AC power in current when phase is taken into account is called what?
True power
142
The ratio of true power to apparent power is called\_\_\_\_\_and, when multiplied by the current, indicates the amount of current that is in phase with the voltage
What is it's formula?
Power Factor
True power = E x I x power factor
143
Circuit components such as light bulbs, heaters, and composition resistors provide resistance to an AC circuit. Circuits containing only these types of devices are called\_\_\_\_\_\_. The current and voltage are in phase with these type of circuits and they both pass through zero in the sine wave at the same time.
Resistive circuits.
144
When the current flow through a conductor changes, the magnetic feild expands or contracts as appropriate. As it does, the lines of flux cut across the conductor and induce a voltage into it. This phenomenon is called \_\_\_\_\_\_\_.
Inductance
145
As the voltage begins to rise and the current in a conductor increases, the expanding lines of flux cut across the conductor and induce a voltage that opposes, or slows down the rising voltage. This induced voltage is sometimes referred to as _________ since it opposes the applied voltage
Counter-electomotive force
146
The symbol for inductance is \_\_\_\_\_and is measured in \_\_\_\_\_\_.
The symbol for inductance is **L** and is measured in **henrys (H).**
One henry of inductance generates one volt of induced voltage when the current changes at the rate of one ampre per second.
147
What law states that the voltage induced into the conductor is of such a polarity that it opposes the change that caused it?
Lenz's Law
148
A conductor's inductance is increased by forming it into a coil. The inductance of the coil is determined by what 4 things?
1. Type of core
2. Number of turns
3. Shape of the coil
4. Wire size
149
Name the circuits and what formula is used?
(Note: Circuit on right are of different values)
150
The tie required for the current to rise to 63.2 percent of its peak value is known as \_\_\_\_\_\_\_of the circuit and is determined by the value of inductance and resistance in the circuit.
What is the formula?
Time Constant
Time Constant = L (henrys) / R (ohms)
For example, a circuit containing 2 henrys of inductance and 50 ohms of resistance has a time constant of 0.04 seconds
Time Constant = 2 henrys / 50 ohms = .04 seconds
151
Inductive reactanceis represented by the symbol ____ and is measured in ohms. What is the formula for determining inductive reactance?
Inductive reactanceis represented by the symbol XL and is measured in ohms.
Formula for determining inductive reactance
XL = 2π*f*L
Where:
π = 3.14
*f* = frequency in cycles per second
L = inductance in henrys
152
Electrical energy can be stored in batteries through an electrochemical process. However, this is not the only means of storing electricity. For example, it can be stored in \_\_\_\_\_\_\_\_caused by an accumulation of electrical charges. The strength of an electrostatic field is determined by the amount of voltage contained by the static charges. A\_\_\_\_\_\_, sometimes called a\_\_\_\_\_\_\_, is a device that stores electrical energy in the electrostatic fields that exist between two conductors that are separated by an insulator, or \_\_\_\_\_\_\_\_\_.
Electrical energy can be stored in batteries through an electrochemical process. However, this is not the only means of storing electricity. For example, it can be stored in **electrostatic fields** caused by an accumulation of electrical charges. The strength of an electrostatic field is determined by the amount of voltage contained by the static charges. A **capacitor**, sometimes called a **condenser**, is a device that stores electrical energy in the electrostatic fields that exist between two conductors that are separated by an insulator, or **dielectric**.
153
Capacitive reactance is the opposition to the flow of alternating current caused by the capacitance in a circuit. What is the symbol and formula for capacitive reactance?
Symbol : Xc
Formula:
154
The ratio of true power to apparent power is called what?
Power Factor
155
