Module 5

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Raju Poulose Kuwait Airways Module 5

Module 5 DIGITAL TECHNIQUES

ELECTRONIC INSTRUMENT SYSTEMS

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Electronic Instrument Systems

1. Typical displays on an EHSI are

* VOR, Map, Plan and weather radar

VOR, Plan, Map and Attitude

Engine indications

2. EADI displays show

pitch, roll and waypoints

* pitch and roll attitudes

heading and weather radar

3. ILS indications on PFD/ND are shown in

green

* magenta

cyan

4. The two sets of flight regulations that a pilot may fly by are

* VFR and IFR

VHF and IFR

VFR and IFU

5. An EADI display showing a moving runway moves down during the final stages of an approach. The aircraft must

fly up

* fly down

hold descent path

6. What are the basic elements for 'Classic T' format?

Airspeed, pitch and roll

Direction, altitude and height

* Airspeed, attitude, altitude and direction

7. An EADI display of flight director commands are coloured

* magenta

red

cyan

At 200ft, during Approach, the Rising Runway starts to move up the EADI display until, at touch down, it touches the bottom of the aircraft symbol. If the Rising Runway start to move down again it means that the aircraft is climbing and should FLY DOWN

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8. An EFIS system ADI displays pitch, roll

* autoland, rad alt, decision height and slip indicator

autoland, altitude, compass rose and flight director bars

autoland, decision height, range to altitude and flight director bars and slip indicator

9. On an EFIS system the weather radar is displayed on

the EADI

* the EHSI

the FMC CDU

10. An EFIS ADI display will show along with pitch and roll

flight director bars, autoland, altitude, range to altitude, decision height

flight director bars, autoland, compass rose, altitude

* decision height, autoland, rad alt , altitude

11. An electronic flight instrument display consists of;

* Mode control panel, Raster and Stroke generator display, microprocessor and Data inputs

ADC, Altimeter, VSI and ASI

ADI, HSI and Symbol generator

12. EFIS systems have two control panels, their purpose is

to provide display control by one control panel whilst the other provides a standby

* one to control the type of EFIS display and the other to select the source of the information being displayed

one for the EADI display and one for the EHSI display

13. A modern Electronic Horizontal Situation Indicator will display the following:

* Waypoints, ILS Steering Information, Distance to go and Magnetic Heading

ILS Steering Information, Flight director information and Glide Slope Deviation

Ground speed, Magnetic Heading, Way points and Localiser

14. What is the fixed feature of an ADI?

The lateral deviation bar

* The aircraft symbol

The glideslope pointer

15. What functions are available on the EHSI?

* Full arc, Wx and Map Mode

Full arc and Wx only

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Full Arc only

16. On an EADI, the Flight Director command bars show

* the required path with respect to the actual path

the actual path with respect to the required path

the path with respect to the horizon

17. During an instrument approach, the glideslope pointer deflects below the glideslope centre mark. This means the aircraft is positioned

below the glideslope

* above the glideslope

to the left of the localiser

18. What does ECAM mean?

Engine Centralised Aircraft Management System

* Electronic Centralised Aircraft Monitoring System

Engine Centralised Aircraft Monitoring System

19. What does EICAS mean?

Electronic indicator and crew alerting system

Electronic indicator and control alerting system

* Engine indicating and Crew alerting system

20. In a typical commercial aircraft Head Up Guidance System

only emergency indications or warnings are displayed to the pilot

all instrument information is displayed on the windshield

* the type of information shown on the attitude director indicator is displayed on a transparent plate

21. On an EHSI in weather radar mode, a severe storm would be shown as

* red areas with black surrounds

orange areas with black or yellow surrounds

blue areas with white background

22. If the glideslope pointer is below the centre mark the aircraft is

* above the glideslope

on the glideslope

below the glideslope

Consider the centre of the G/S scale as the aircraft position and the pointer as the centre of the G/S beam

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23. Engine parameters are displayed on

EHSI

FMSCDU

* ECAM

24. A complete EFIS installation in an aircraft is made up of

right (captain) and left (co-pilot)

left (captain) and right (co-pilot)

* either left (captain) and right (co-pilot), or right (captain) and left (co-pilot)

25. The EFIS system consists of

* EADI, EHSI, Symbol generators

EHSI, Mode control panel, EADI

Mode control Panel, RDMI, EHSI

26. With radio coupled autopilot, what are the inputs?

ADF and VOR

ADF and ILS

* ILS and VOR

27. During flight (non fault conditions) the EICAS system displays on the lower CRT

flight phase page

synoptic display

* secondary engine parameters

28. What would you expect to see displayed on an EADI display?

Course information, weather radar, way point alert and bearing pointers

* Flight director command bars, slip indicator, rate to altitude and autoland

Compass heading, selected heading and VOR

29. What does EFIS mean?

Electronic Fire Indication Signal

* Electronic Flight Instrument System

Electronic Flight Information System

30. On a modern 'glass cockpit' aircraft, engine information will be displayed on

* ECAM

FMS

could be either, as most helicopters are the other way round when compared to aeroplanes

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EFIS

31. In a basic 'T' configuration

* the ASI appears on the left and the Altimeter appears on the right

the ADI appears on the left and the HSI appears on the right

the ADI appears on the left and the ASI appears on the right

32. What instrument includes a display of a rising runway?

* EADI

ECAM

EHSI

33. In an EIS (Electronic Instrument System), what does EAD stand for?

* Engine and Alert Display

Electronic Attitude Display

Electronic Alert Display

34. Radio altitude is displayed on an EFIS system

* on the Electronic Attitude Direction Indicator

on the RMI

on the Electronic Horizontal Situation Indicator

35. A weather radar image can be displayed on the ND on all modes except

* plan

arc

nav rose

36. Cockpit panels have a matt colour finish. The purpose is

so that pilots feel more comfortable during daytime

so that dust and dirt are less evident on panels

* so that the amount of glare is reduced to minimum

Numbering Systems

1. 101012 + 110012 =

468

462

* 4610 101012 + 110012 = 1011102 = 4610

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2. The Binary number 10101 is equivalent to the decimal number

19

* 21

35

3. The decimal number 37 is represented by the octal number

37

* 45

54

4. Convert 0111012 to octal

25

33

* 35

5. F80 hexadecimal converts to binary

3968

101100000001

* 111110000000

6. What is hex 110 in decimal?

* 272

282

32

7. Convert the binary word 1100 to decimal

11

* 12

16

8. If a data message is made up of 1s and 0s, it is

* digital

binary

analogue

9. Convert the binary word 1110 to decimal

* 14

15

011=1x21 +1x20 =2+1=3 and 101=1x22 +1x20 =4+1=5. Ie 35.

F80, F=15,

ie 15=1111, 8=1000, 0=0000

1x162 +1x161 +0x160 =256+16=272

1x23 +1x22 +0x21 +0x20 =8+4=12

1x23 +1x22 +1x21 +0x20 =8+4+2=12

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12

10. Convert the binary number 110010 to decimal.

34

80

* 50

11. Convert the hexadecimal number D into decimal.

15

14

* 13

12. Convert decimal 15 into binary.

1110

1101

* 1111

13. Convert decimal 15 into hexadecimal.

G

* F

E

14. What is 345 in binary?

* 101011001

100111001

110011001

15. A hexadecimal is a number to base

2

* 16

8

16. 1012 converted to decimal is

52

210

* 510

17. The decimal number 7 expressed as a binary number is

1012

1x25 +1x24 +0x23 +0x22 +1x21 +0x20 =32+16+2=50

1x23 +1x22 +1x21 +1x20 =8+4+2+1=15

1x28 +0x27+1x26+0x25 +1x24 +1x23 +0x22 +0x21 +1x20=256+64+16+8+1=345

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* 1112

72

18. Convert 011101 binary to octal.

25

* 35

33

19. Binary Number: 110010 is

* 50

80

34

20. The binary number 11010111 is expressed as a decimal is

107

53

* 215

21. The octal number 1001 expressed as a decimal is

613

* 513

713

22. What is 0111000012 in Octal?

* 3418

28110

2258

23. The binary number 10101000111001012 in hexadecimal is

FFFF16

* A8E516

22BC16

24. A computer message 3B4 is

binary

* hexadecimal

octa

25. 2D in decimal is

10


43

41

* 45

26. 84 decimal in hexadecimal is

* 54

5f

f4

27. 16 hexadecimal converted to decimal is equivalent to

48

38

* 22

28. Decimal 10 converted to binary is

1001

1111

* 1010

29. What systems uses base 10?

Octal

Digital

* Decimal

30. What systems use base 16?

BCD

* Hexadecimal

Octal

31. What is used for the base of 10?

Digital

Octal

* Decimal

32. What is 44 in hexadecimal?

* 2c

2d

2F

(2 x 16) + (12 x 1) = 44 (c = 12)

D=13, 2x161 +13x160 =45

84 binary=1010100 ie in hexadecimal, 101=5 and 0100=4 ie54.

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33. An octal format hexadecimal number 3F written as binary would be

110 111

101 011

* 111 111

34. In a computer, the address 3B8 is

octal

decimal

* hexadecimal

35. Hexadecimal 5C is what in binary?

1011111

* 1011100

1110100

36. Binary 11001101 converted to octal is

12E

* 315

205

37. What is the binary notation for 29?

0001 0110

0010 1001

* 0001 1101

Data Conversion

1. In A/D conversion, a signals bandwidth represents

* the maximum frequency range occupied by a signal

the frequency of a signal

the minimum frequency range occupied by a signal

2. What does 1 represent in an analogue system?

High frequency

Switches open, unmagnetised

* Switches closed, magnetised

3. Analogue logic 1 is

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* closed circuit, Logic Q=1

closed switch, Logic Q=0

open circuit

4. An A to D converter uses successive approximation to

increase resolution

* increase speed

increase accuracy

5. An analogue to digital converter where it counts up to binary state equal to the analogue input and then back down when this is reached is a

* a ramp type converter

successive approximation counter

flash type converter

6. Within a computer controlled flight system, position feedback is converted from

* analogue to digital

digital to analogue

position feedback to rate feedback

7. The advantage of digital sound over analogue sound is

greater selectivity

* minimal error and noise

the narrow bandwidth allows it to copy exactly

8. A given transducer provides a voltage which corresponds to true heading. This voltage can be converted to 'bits' by using a

commutator

digital to analogue converter

* analogue to digital converter

9. An R-2R Converter has values of resistance

whose precision are accurate

* whose precision are not accurate

whose relative precision are accurate

10. Audio sounds recorded digitally

* are superior quality and greater bandwidth

are narrow bandwidth

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are not as accurate due to clipping and input errors

11. What is the quickest method of analogue to digital conversion?

Single ramp method

Voltage to frequency

* Flash converter

12. A number represented as a physical quantity, e.g. voltage or speed of rotation is

* analogue

maximum value

digital

13. An R-2R D to A converter uses

resistors whose values are logarithmic

* two values of resistors whose precision is not important

two values of precision resistors

14. An ADC uses successive approximation to

increase resolution

* increase speed

increase accuracy

15. Digital signals can be represented

* by a series of integers

only as a binary value

by real numbers

16. If a signal has quantity in volts and physical position it is

digital

synchronous

* analogue

17. In an R-2R ladder converter the values of resistors

* do not need to be of precise values

are precise

only the first resistor need to be precise

18. Physical variables in quantitative forms, such as voltage or angular rotation of a shaft are

* analogue

This is the definition of an analogue signal

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digital

binary

Data Buses

1. In arinc 629, LRUs are programmed

to transmit all at the same time

* to transmit one at a time

so that one transmits and one receives

2. The maximum number of terminals connecting to a MIL-STD-1553B databus is

120

20

* 31

3. How is the data transmitted on an ARINC 429 bus?

* Asynchronous and serial

Asynchronous and parallel

Synchronous and parallel

4. What is a parity bit used for on an ARINC429 bus?

Synchronization

Data word

* Fault/self check

5. A bus which supports the transfer of data in both directions is referred to as

Asynchronous

* Bidirectional

Universal

6. The maximum data rate supported MIL-STD-1553 is

12.5 Kbps

* 1 Mbps

100 Kbps

7. Manchester II encodes logic 1 with a voltage transition from

* a high to low state

a specific voltage value

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a low to high state

8. The maximum data rate supported by the FDDI bus is

1 Mbps

* 100 Mbps

10 Mbps

9. In aircraft use, fibre optic cables should comply with

ARINC 629 standard

ARINC 429 standard

* ARINC 636 standard

10. The ARINC 429 data word is

16 bits long

* 32 bits long

64 bits long

11. ARINC 629 databus is

* two cables, bi directional

two cables, uni-directional

one cable, bi-directional

12. The ARINC 429 standard uses

* odd parity checking

no parity checking

even parity checking

13. ARINC 629 runs at a baud rate of

50 kBaud

100 kBaud

* 2000 kBaud

14. An ARINC 573 data bus is used

to supply digital inputs from a Symbol Generator to the EADI and EHSI

* to input into a Digital Flight Data Recorder

to input into a FDR Digital Acquisition Unit

15. An ARINC 429 bus uses

a single twin wire cable for each transmitter

The FDR can have different inputs depending upon the age of the system, modern systems use ARINC 573. The inputs to FDR DAU are only analogue, discreet and ARINC 429. The interface between SGUs, EADI and EHSI is only ARINC 429

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* a twisted shielded pair of wires

two bi-directional twin sheathed and earthed wires

16. The ARINC 429 data bus word systems use

decimal numbering

hexadecimal numbering

* binary coded decimal

17. ARINC 573 is related to what system?

* FDR

Weather Radar

INS

18. ARINC 629 current mode couplers are

resistive

* inductive

capacitive

19. ARINC 629 databus is

* one bus, bi-directional data flow

two buses, bi-directional data flow

two buses, unidirectional

20. Normal transmission order of ARINC 629 LRUs in periodic mode is in order of

shortest to largest TI

* power up

shortest to largest TG

21. In an ARINC 429 wordstring, bits 1 to 8 represent the

destination LRU address

message

* monitored parameter

22. MIL-STD-1533 is a data bus for

* Digital Information Transfer System

Flight Data Recorders

Inertial Reference System

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23. ARINC 629 periodic mode is used for

transferring data only on events important to aircraft operation

database loads

* normal operation

24. How is data coupled to an ARINC 629 data bus?

* By an inductive pickup

By a capacitive pickup

By a resistive pickup

25. How does MIL-STD-1533 put data onto the databus?

Through the bus controller

* SSIFU (sub-system interface unit)

R1 (remote terminal)

26. The parity bit in digital information is used

* to check the validity of data information

for BITE programs

to check the status of the system

27. ARINC 429 SDI word format is at bits

1 - 8

* 9 - 10

32

28. What is the parity bit for on an ARINC 429 bus?

To delay the signal

To act as a terminal gap in an emergency

* To check for corruption during transmission of a word

29. An ARINC 429 word label format is

* octal

binary

hexadecimal

30. How many LRUs can be connected to an ARINC 429 data bus?

120

* 20

18


60

31. ARINC 629 terminal transmit interval is

when all transmissions are quiet

* common to each terminal

unique to each terminal

32. ARINC 429 data bus systems uses

hexadecimal numbering

decimal numbering

* binary coded decimal

33. An ARINC 429 Binary Coded Decimal word occupies word bits

* 11 - 29

11 - 28

1 - 8

34. An ARINC 429 system uses a

16 bit word over a twisted pair of wires

20 bit word over a bi-directional bus

* 32 bit word over a twisted pair of wires

35. An ARINC 629 characteristic is

* data can transmit in both directions down the data bus

all LRUs can transmit at the same time

all LRUs can transmit and receive at the same time

36. What limits the number of ARINC 429 receivers on a bus?

* The parallel input impedance

The speed and size

The weight

37. Data is transferred on the MIL-STD-1553B by

non return to zero

bi-polar return to zero

* Manchester bi-phase

38. How are engine indications sent to the FDR?

* Via ARINC 573

Two versions of ARINC 429. BCD uses 11 - 29, Binary uses 11 - 28.

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Source isolated

Via ARINC 629

39. What system uses base 8?

ARINC 629

* ARINC 429, in dataword labels only

ARINC 573

40. On an ARINC 629 data bus, the maximum amount of current-mode couplers per data bus is

* 120

46

64

41. To connect an LRU to an ARINC 629 data bus

a terminal controller and interface module only is required

current mode coupler, terminal controller and a production break is required

* a current mode coupler, serial interface module and terminal controller is required

42. A current-mode coupler contains an E-Core assembly. The purpose of the E-Core is to

provide effective screening of the signal through the current-mode coupler

* couple the signal to the data bus

enable easy access for monitoring of the signal

43. The ARINC 429 low rate of transmission is

100 kbits/second with high of 12-14 Mbits/second

* 12-14 Kbits/second with high of 100 kBits/second

12-14 Mbits/second with high of 100 Mbits/second

44. What is the highest speed in ARINC 429?

* 100 kbps

2 Mbps

100 bps

45. What is the slowest speed for ARINC 429?

10 kbps

100 kbps

* 12.5 kbps

46. Where is the pass and fail of an ARINC 429 code indicated?

120 LRUs maximum (but the B777 uses 46)

20


* SSM field

SDI field

Label field

47. What is the encoding method used in ARINC 429?

Bipolar NRZ

* Bipolar RZ

Manchester coding

48. An ARINC 629 bus cable is a twisted pair of wires with

a 130 ohm resistor at one end

* a 130 ohm resistor at both ends

a 230 ohm resistor at one end

49. How many voltage levels does ARINC 429 have?

* 3

1

2

50. An ARINC 629 stub cable

* connects bi-directional data between the LRU and current mode coupler

connects bi-directional data between two LRUs

connects single directional data between the LRU and current mode coupler

51. Care must be taken when installing ARINC 629 cables into bus panels, damage to cables can cause

arcing of high voltage signals

standing waves

* corrosion of the conductor

52. An aircraft databus system

cannot use both ARINC 629 and ARINC 429 data buses.

* can use both systems, ARINC 629 and ARINC 429 via system card files and signal gateways

can use both ARINC 629 and ARINC 429 as they are compatible.

53. ARINC 629 is used for

a backup to ARINC 429

* normal flight

emergency only

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54. Once an ARINC 629 LRU has transmitted a message it will wait how long before transmitting again?

Until the start of the terminal gap

* Until the end of the transmit interval

Until the end of the synchronization gap.

55. How is the word label 206 written in ARINC 429?

* Octal 01100001

Binary 11000110

Decimal 206

56. What is ARINC 561 used for?

Fly by Wire systems

Flight Data Recorder systems

* Inertial Navigation Systems

57. An ARINC data word is bits 11-29, if bits 11-18 are patched which of the following would be the LSB bit?

21

* 29

19

58. Fibreoptic databus links are

simplex

one way data buses

* bi-directional

59. ARINC 429 is

* simplex

full duplex

half duplex

60. A signal in an ARINC 629 system uses

a pair of wires per transmitter unit

a single wire

* a twisted pair of wires or fibre optics

61. An in-series ARINC 429 system transmits using

wave division multiplexing

* time division multiplexing

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encoder

62. A terminal controller

is repetitive transmitting

transmits only when addressed

* will transmit only once during each transmit interval

63. The number of LRUs which transmit/receive on ARINC-429 is dependent upon

size of S.D.I

speed of transmission & size of aircraft systems

* parallel input impedance

64. One of the ARINC 429 formats is

hexadecimal

octal

* BCD

65. A group of bits transmitted at the same time is

* parallel data

serial data

a clock signal

66. The ARINC 429 system uses which of the following system to transfer data?

Non return to zero

* Bi-polar return to zero

Harvard bi phase

67. Data is transferred on the MIL-STD-1553B by using

* Manchester bi-phase

non return to zero

bipolar return to zero

68. The general arrangement of ARINC 629 includes

current mode coupler, databus cable only

databus cable, stub cable, voltage mode coupler

* databus cable, current mode coupler, stub cable

69. ARINC 629 Databus cables are terminated using

100 ohms resistor

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* 130 ohms resistor

25 ohms resistor

70. In ARINC 429 data field is bits 11 to 28. If the bits 11 to 18 had pad bits, the L.S.B. Of the data would be

bit 11

* bit 19

bit 28

71. The BCD data field of ARINC 429 is contained within bits

1- 8

* 11- 29

11- 28

72. ARINC 629 is transmitted using

SWG 28 wire

* fibre optics or twisted pair of wires

single wire for each transmitter

73. A simplex system has

1 bus controller and multiple receivers

* 1 transmitter and multiple receivers

1 bus controller and 1 remote terminal

74. To create a bi-directional communications link within an ARINC 429 system

only one databus is required

* two databuses are required

four databuses are required

75. Why does an ARINC databus system send data to LRUs in series?

Takes less time

More information can be sent

* Saves weight

76. Can an LRU transmit and receive on more than one 629 bus?

* Yes

No

Only if paralleled

Binary Word is 11 - 28. BCD Word is 11 - 29

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77. ARINC 629 LRUs transmit

when signal gap is sensed

when addressed

* when terminal gap is sensed

78. An ARINC 429 BCD word occupies bits 11-29, if 11-15 are filled with padders then the LSB of the word will be

* 16

29

11

79. A simplex system has

* one transmitter, many receivers

one transmitter, one receiver

a bus controller and separate controller

80. In an Arinc 429 Word label-representing heading is 320, this is represented in bits 1- 8 as

01011001

* 00001011

01101000

81. In ARINC 629 aperiodic mode, LRUs transmit in order of

power up

* shortest terminal gap to longest terminal gap

longest terminal gap to shortest terminal gap

82. ARINC 629, aperiodic mode is used

for normal operation

for landing and approach operation

* for database loads

83. How is ARINC 429 bi-directional data transfer achieved?

* Using two data buses

Via a twisted pair of shielded cables

Via a current mode coupler

84. The data format used to transmit a signal to the flight data recorder

Bi-Polar RZ 12 bit

Manchester 2 bi-phase 12 bit

Octal 320 converted to binary, and reversed.

B777 MM 23-91-00 pg 41. Periodic mode is for normal operation. Aperiodic mode is for non-normal operation and large information transfer such as database loads and operating software loads.

25


* Harvard bi-phase 12 bit

85. The output voltage of ARINC 429 signal is

* +10v to -10v

-5v

+5v

86. An ARINC 629 label word is

8 bits

10 bits

* 12 bits

87. The TX/RX of ARINC 629 is

switching

* multiplex/demultiplex

encoder/decoder

88. Terminal gap in ARINC 629 is

always the same period

* can be changed by adjusting the rx/tx software

flexible

89. How does ARINC 629 bus transmit and receive information?

* Inductive coupling

Sockets and pins

Optical coupling

90. What is ARINC 561 used for?

To specify Flight Data Recorder data bus

To specify LRU pin-outs

* To specify Inertial Nav data bus

91. What is the purpose of the parity bit on an ARINC 429 bus?

To indicate that the data is digital

To indicate if the data is analogue

* To indicate to the receiver that the data is valid

92. ARINC 429 is

Multiple Source Multiple Sink system

12-bit label field, 4-bit label extension, single parity, 3-bit time hi-lo synch pulse. 20 bit in total

26


* Single Source Multiple Sink System

Single Source Single Sink system

93. What is the purpose of intermediate production breaks in ARINC 429 or 629 Data cables?

To allow connection of new cables to the existing ones in case of a modification

* To allow maintenance personnel to divide the right and left system buses into two parts for easy removal and installation

Cables are only manufactured 40 feet long

94. Where is the parity bit installed in a data word?

Front

* End MSB

Middle

95. RZ bi-polar modulation consists of bits which are one of __________ states?

* Three

Two

Eight

96. In the ARINC 429 digital information transfer system, data may travel in:

* one direction only

both directions on the same bus sequentially by time multiplexing

both directions on the same bus simultaneously

97. An ARINC 629 data word

includes an 8 bit label and a 16 bit data field

* has only 20 bits

comprises up to 256 data bits

98. In an ARINC 429 digital word bit number 32 is used for

identifying word type

terminating the data field

* checking parity

99. What connects an LRU to the Bus Coupler in an ARINC 629 Data Bus?

Interconnect Cable

* Stub Cable

Patch Cord

27


Logic Circuits

1. Adding invertors to the two inputs of an AND gate makes a

NAND gate

OR gate

NOR gate

2. To get logic 1 using this gate

A and B = 1

A or B = 1

A and B = 0

3. The output of an AND gate having two inputs A and B is logic 1. The two inputs will have the logic states of

A = 0, B = 0

A = 1, B = 0

A = 1, B = 1

4. When the voltage that represents a logic 1 state is less than the voltage that represents a logic 0 state, the logic being used is

negative

positive

either positive or negative

5. A B S

0 0 0

0 1 1

1 0 1

1 1 0

What type of gate is this?

E-OR

NAND

NOT

6. An AND gate output is 1 when inputs are

E-OR is another name for XOR

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both 0

1 and 0

both 1

7. When will a NAND gate give logic 0 at the output?

When both inputs are at 0

When the inputs are different

When both inputs are at 1

8. Making an inverter from a NAND or NOR gate is achieved by

inverting the input

connecting two in series

connecting the inputs

9. What sort of gate is this?

Or gate

NOR gate

NOT gate

10. What does the logic circuit shown represent?

Analogue to Digital Converter

Full Adder Circuit

3-way converter

11. In Positive Logic representation

29


both states have same positive voltages but stage 1 has more current

state 0 is more positive than state 1

state 1 is more positive than state 0

12. The output of a NOT gate is logic 1. The input is

both logic 1

logic 0

logic 1

13. What is this truth table?

AND gate

NOT gate

NOR gate

14. What sort of gate requires two negative input voltages to operate?

XOR

NOT

NAND

15. Switching within logic gates is normally achieved with the use of

diodes

relays

BTB's

16. The output of an OR gate having two inputs A and B is logic 0. The two inputs will have the logic states of

A = 0, B = 0

A = 0, B = 1

A = 1, B = 0

17. Which logic gate has both inputs 'high' to get an output?

NAND gate

XOR gate

AND gate

A negative input voltage has the same effect as an input of 0 volts. 2-inputs specified, so cannot be a NOT gate.

30


18. This truth table is for a

NAND gate

OR gate

AND gate

19. A NAND and NOR to become a NOT gate have

inputs inverted

inputs connected together

outputs inverted

20. What logic gate would this circuit represent?

NAND Gate

NOR gate

AND gate

21. What input is required to activate the relay shown?

A=0 B=1

A=1 B=1

A=1 B=0

22. Logic gates internal operating mechanisms are produced from

diodes

31


transistors

thin film resistors

23. What Logic Gate does this switch circuit indicate?

OR gate

NOR gate

AND gate

24. A logic 1 may be represented in an analogue system by (where Q is an output of a latch / flip-flop)

positive / magnetised / Q

switch closed / light off / Not Q

switch open / light on / Q

25. What sort of gate requires two positive voltages to operate?

OR

AND

NOT

26. What is this symbol?

Exclusive NOR gate

Exclusive OR gate

Exclusive AND gate

27. An AND gate with inverted inputs and an inverted output is equivalent to

an AND gate

a NOR gate

an OR gate

32


28. Which logic gate can be represented as a parallel circuit?

OR gate

Exclusive OR gate

NAND gate

29. A NAND gate has inputs A and B and output C. If the output (c) was zero, what are the inputs?

A=0 B=0

A=1 B=1

A=1 B=0

30. The most appropriate logic family for use in a portable item of test equipment is

Low-power Schottky TTL

MOS

TTL

31. What is the equivalent of this gate?

X = (NOT-A + NOT-B)

X = (A + B)NOT

X = (A.B)NOT

32. A NOR gate with both inputs inverted becomes a

NAND gate

AND gate

OR gate

33. A CMOS logic gate is operated from a 12V supply. If a voltage of 3V is measured at the input to the gate, this would be considered equivalent to:

Indeterminate

logic 1

logic 0

34. Which logic gate has this truth table?

33


Exclusive OR

NAND

NOT

35. Logic gates internal operating mechanisms are produced from

thin film resistors

diodes

transistor

36. The truth table of A =0011 B=0101 and X =0110 indicates that the logic device is

an AND gate

a NOR gate

an EXCLUSIVE OR gate

Basic Computer Structure

1. A BYTE is usually

a six bit word

a 12 bit word

an 8 bit word

2. A typical example of a mass storage memory device which is also WORM (Write Once Read Many) is

a magnetic tape

an IC

a CD Rom

3. In a volatile bi-stable memory circuit

the memory is lost as soon as power is removed

the memory is retained indefinably

the memory needs to be refreshed constantly, even when power is on

4. Ferrite medium is used for computer memory because

it is light

it has low eddy current losses

34


data is stored after the power is removed

5. A computer using RAM would utilise

an integrated circuit (chip)

a compact disc

magnetic tape

6. What is EPROM?

Erasable programming read only module

Enhanced programmable read only memory

Erasable programmable read only memory

7. What is the advantage of series over parallel message sending?

Only one pair of conductors

Quicker

More information sent

8. In a computer memory device, which one of these has the slowest access time?

8mm video tape

magnetic tape

floppy disk

9. Which would have the least components?

LSI

CPU

ALU

10. The advantage of DRAM over SRAM is

has a larger storage capacity per chip area

they operate slower

are cheaper to manufacture

11. A computer must have which of the following to operate?

ROM/RAM, Buses, Monitor, CPU

RAM, I/O devices, Buses, Printer

RAM/ROM, I/O devices, OS, Buses, Clock

12. A common used material in computer manufacturing is

permeamag material

8mm video tape is not (and never has been) a computer memory device

Ferromagnetic material is that which hard-drives and floppy drives are made from

35


ferrite material

ferromagnetic material

13. What is a baud?

A block of data

A byte of data

A bit of data

14. REAL TIME computers are ones that

are up-to-date

store data as soon as it is retrieved

display data as soon as it is processed

15. Magnetic materials are used in

ROMs only

EPROM

some RAMs

16. A typical example of a mass storage device is

CD

IC

magnetic tape

17. Data is usually stored in

ROM

RAM

EEPROM

18. What is the definition of baud rate?

1 word per second

1 bit per second

1 byte per second

19. How many bytes can be carried in a 32bit word?

2 bytes

8 bytes

4 bytes

Fibre Optics

36


1. A disadvantage of a fibre optic cable is

shallow bend radius allowed

end terminals are susceptible to environmental contamination

couplings susceptible to ingress of fluid

2. A fibreoptic cable to LRU connector should be connected

using torque-loaded pliers

hand tight only

very carefully to ensure alignment and reduce light loss

3. Two connected fibre optic cable ends are parallel but not quite touching. This is called

lens connector

end fire coupling

end to end coupling

4. Most fibreoptic connectors are designed so

the connectors can not be over tightened

the connector can not be replaced on the aircraft

the receptacle has to be torqued to a designated value to ensure correct alignment

5. A fibre optic cable consists of

a silica glass core with a cladding having a higher refractive index

a silica glass core with a cladding having a lower refractive index

a plastic core with a cladding having a higher refractive index

6. Fibreoptic cables use

reflective outer shell

refractive outer shell

reflective inner shell

7. Some of the advantages of fibre optic cable over copper cables are

smaller in size and weight, non conductive, higher security and higher bandwidth

non conductive, smaller in size and weight, easy to manufacture and assemble and higher security

non conductive, easy to manufacture and assemble, more robust, cheap

8. What maintenance problems are associated with fibreoptics?

Kinking and contamination of connectors

Corrosion

The outer cladding is glass, so it is refractive (but less so than the core). Cladding causes Total Internal Reflection (TIR), so question can be interpreted in two ways.

37


Earthing faults

9. Fibreoptics relies on

light reflecting off cladding

fibre absorbing light

light escaping cladding

10. In fibreoptics the wavelength of the light is

less than visible light

more than visible light

equal to that of visible light

11. What is the advantage of a single mode fibreoptic over ordinary wire?

Small bend radius

Not prone to damage

Large bandwidth

12. A fibreoptic light source is normally

a filament lamp

a laser or LED

a strobe light

13. Light transmission in a fibreoptic cable is due to

repeated internal reflection

defraction of the light

refraction of the light

14. Star couplers are used in fibre optic systems for

amplifying the low power optical signals

splicing lengths of optical fibre together

equally distributing signals to equipments

15. What kind of light is used in a fibre optic systems?

Infrared

Ultraviolet

Visible

16. What is the main cause of attenuation in fibreoptics?

Refractive index

38


Poor termination

Bends in the cable

17. What is the main disadvantage of a fibre optic data bus?

Expensive to install

Bend radius and moisture ingress at connections

Less strong and durable when compared to twisted pair and coaxial cable

18. Fibre optic cables

are immune to EMI

attenuate EMI

are susceptible to EMI

19. What does a fibreoptic star connection do?

Shares a common bandwidth of a common cable

Provides a continuous loop of fibre interconnecting all nodes

Provides direct point-to-point services to units on dedicated lines emanating from the central hub

20. Speed of light in a fibreoptic fibre

is always the same no matter what material it is

increases if it passes through material of higher refractive index

is never greater then the speed of light in free space

11. Electronic Displays

1. A shadow masks CRT works by

two layers of phosphor, the top layer is red, the bottom layer is green

one layer of red, green and blue dot matrix excited by their own electrode guns

three layers of phosphor coating, red, green and blue

2. The inside of a CRT consists of

a phosphor coating and rare mercury gas

iodine and rare mercury gas

an oxide coating and rare mercury gas

3. CRT horizontal beam control is achieved by a

square wave

sawtooth wave

sinusoidal wave

39


4. In a CRT, if the magnetic field is parallel to the Y plates, what will be the direction of the electron beam movement?

No movement

Horizontal

Vertical

5. Primary colours of a CRT are

red, blue and yellow

red, green and blue

red, green and yellow

6. What are the effects of the X and Y plates on a CRT?

X plates move the beam vertically, Y plates move the beam horizontally

Y plates move the beam vertically, X plates move the beam horizontally

X and Y plates can move the beam in either direction

7. EADI sky and ground display is provided by

synthetic TV signals

raster scan

stroke pulse

8. What frequency creates the raster effect on a CRT?

250Hz

400 Hz

50/60 Hz

9. The sweep waveform used on a electromagnetic CRT is

sinusoidal

trapezoidal

sawtooth

10. What shape does the waveform take to counter the impedance effect of the coils in an electromagnetic controlled CRT?

Sawtooth

Trapezoid

Rectangular

11. Magnetic deflection in a CRT is achieved by

a sinusoidal voltage

40


a trapezoidal waveform

a sawtooth waveform

12. The timebase in a CRT consists of

an amplifier only

an amplifier and an oscillator

an oscillator only

13. What creates the raster effect on a CRT?

Sawtooth frequency

Trapezoidal frequency

Sinusoidal frequency

14. The trace of an oscilloscope begins when the input level is approximately 10 volts but the peak values indicate 20 volts. What can be done to cause the trace to begin at zero volts?

Adjust the trigger level to zero volts trigger.

Adjust the volt per division to zero volts/cm

Adjust the horizontal position to show the full trace on the screen

15. How are colours produced on an active matrix LCD (AMLCD)?

By controlling the twist of the liquid crystal display immediately behind each of the three colour filters in each pixel

By synchronizing the colour modulation of the back light with the twisting of the liquid crystal located behind each pixel

By controlling the intensity of the tri-colour emitters in each pixel.

16. LCD screens are driven by

fixed current DC voltage

AC voltage

variable current DC voltage

17. A Liquid Crystal Display (LCD) has the advantage over a CRT that

it displays more colours

it requires less servicing

it requires no cooling

18. The release of a photon by another photon is the principle of

a zener diode

an LED

41


a photo diode

19. If a magnetic field is parallel to the X plates in a CRT, which way will the beam move?

Vertically

Diagonally

Horizontally

20. An LED display is

monochrome only

red and green

high definition

21. An LCD display uses what type of power supply?

Continuous AC

DC voltage

Variable level DC voltage

22. A beam deflection on EFIS displays are

solid state

electrostatic

electromagnetic

23. The supply to an LCD is

voltage restricted DC

AC

current restricted DC

24. An LED will emit light when

it is reverse biased

it is forward biased

either forward or reverse biased if a sufficient level of ac voltage is applied

25. A CRT display has the advantage over an LCD display of a

large viewing angle

more energy efficient

brighter clearer output

26. To display a circle on a CRT you use

2 sine waves 180 degrees out of phase

42


2 square wave 90 degrees out of phase

2 sine waves 90 degrees out of phase

27. To deflect the beam of a CRT horizontally, coils are placed on the neck of the tube

one on the side, one at the bottom

top and bottom

each side

28. If the magnetic deflection plates produce a magnetic field which is parallel to the horizontal then the trace is deflected in

vertical axis

horizontal axis

circular motion

29. The most common CRT control for an EFIS system screen is

a combined system

an electrostatic system

an electromagnetic system

30. L.E.D.s can give

high definition displays

monochrome displays only

red and green displays only

31. At low ambient temperatures, an LCD screen

viewing angle becomes larger

is slower to update as data changes

loses contrast

32. Colour CRT shadow mask screen resolution is

600 lines per scan

400 lines per square inch

84 triads

33. An LCD display

is monochrome

has infinite colours

has three colours only

34. A segmented configuration for the display of alphanumeric data requires

43


at least 13 segments for all upper and lower case letters

the starburst display for numbers and lower case letters only.

16 segments to display the full range of capital letters and numerals

35. Electronic CRT beam display is used typically in

IRU control display units.

distance measuring indicators; digital counters

weather radar indicators

36. In a colour cathode ray tube, how is the phosphor arranged in the tube?

Layers of red, blue and green

A red layer on the front with two green layers behind it

A single phosphor layer containing red, green and blue

37. A colour LCD which is back lit has

three colours

an infinite amount of colours

monochrome

38. A dot matrix/LED construction is

4x7 or a 9x5 rolling end display



39. What are the advantages of an LCD display over an LED?

There are no advantages

It uses less current

It is brighter

40. A seven segment display is used to

display octal and decimal numbers only

display alpha-numeric characters

display octal and binary numbers only

41. How are Alphanumeric Displays produced on a CRT?

by the use of X & Y EM Coils

Raster scanning

By Stroke pulse

44


42. The Shorter lead near the Flat portion of an LED is the

Gate

Anode

Cathode

43. 'Submarining' is

caused by the inability of some LCD screens to respond to fast moving images on screen

a CRT screen defect which can usually be remedied by degaussing the screen

the process used to form liquid crystals into a flat screen

Electrostatic Sensitive Devices

1. A flight deck CRT LRU is being replaced. What does the ESDS label indicate?

Remove power before connecting

Do not touch plug pins or leave them exposed

Wrist straps should be worn

2. A humid atmosphere

reduces static charge

has no effect on the level of charge

eliminates static charge

3. Electrostatic discharge occurs when

materials are rubbed together or pulled apart

the ground lead on a wrist strap touches the skin

materials of different potential are brought in close proximity to each other

4. With a relative humidity of 10% to 20%, if you walked over a carpet what electrostatic voltage value would you expect to see?

12,000 volts

6,000 volts

35,000 volts

5. When handling PCB's labelled ESDS, what precaution are taken?

Isolate electrical power before installing on Aircraft

First earth with aircraft then to it

45


Do not touch its pins as copper contamination can occur

6. What precautions are required when removing ESDS equipment?

Wear a wrist strap connected to an approved ground point

No special precautions are required

Keep one hand on the airframe

7. Which of the following ESDS devices can withstand higher static electricity voltage?

ECL

MOSFET

SCR

8. ESDS bags are sealed by

twine (100% cotton)

ESDS labels

zip locks

9. When removing a PC card from an ESDS assembly ensure a low current path between

aircraft and ground

you and the assembly

you and the aircraft

10. After attaching a wrist strap to your wrist (which is connected to aircraft ground), prior to removal of ESDS equipment, the resistance measured

between the strap and the pin ground must be >1 Megohms

between the strap and the pin ground must be <1 megohms

between your skin and the pin ground must be >1 megohms

11. Before removing an assembly from an aircraft, with regards to HIRF, you must first ensure that there is minimum current flow between

you and the assembly

the assembly and the aircraft

you and the aircraft

12. A wrist band must be worn when working with ESDS devices

to prevent the operator from getting an electric shock

to dissipate and prevent static build-up on the operator

to dissipate static charge on the device

13. Before fitting a Printed Circuit Board you should check the

Boeing manual says 100% cotton twine. Other manuals say ESDS label. However, it could be considered that ESDS labels do not 'seal'.

Answer found in Boeing SWPM. 20-41-01 3(2) (e) Hold the red lead of the (test) meter between the forefinger and the thumb. The acceptable range is less than 10,000,000 ohms. Lower limit of range however seems to vary.

46


resistance between skin and strap end plug is more than 1 megohms

resistance between strap and strap end plug is less than 1 megohms

resistance between skin and strap end plug is less than 10 megohms

14. The resistance of the wrist strap used as part of anti static precautions should be

20 megohm - 200 megohm

250 kilohm - 1.5 megohm

0 - 200 ohm

15. During an EFIS screen fit

do not touch terminals

use bonding strap

no tooling is required

Software Management Control

1. If due to a software error in an aircraft system that would cause injuries to some of the occupants, the system has a software criticality category of

major effect

minor effect

hazardous effect

2. An aircraft system that, should it fail due to a software error, would cause a slight increase in crew workload, has a software level of

C

B

D

3. Requirements for software control can be found in

JAR AWO

AWN 43

JAR OPS

4. What is the definition of level one software?

Non-essential

Essential

Critical

47


5. An aircraft system allocated a software level of C that, should it fail due to a software error, may cause

injuries to a large proportion of occupants

no injuries to occupants

injuries to some occupants

6. An aircraft system that, should it fail due to a software error, would cause a significant reduction in safety margins may also cause

injuries to some occupants

the loss of the aircraft

no injuries to occupants

7. As far as a software product is concerned

the 'Validation' phase is done to the software rather than to the component.

the 'Verification' phase includes performance testing a programmed EPROM

the 'Software Release' phase is the same as the 'Finished Product' phase

8. An aircraft system with a software level of D, should it fail due to a software error, may cause the aircraft safety margin to be

significantly decreased

slightly decreased

slightly increased

9. Who is responsible for producing the operational program of the FMS?

The pilot

The engineer

The manufacturer

10. An aircraft system allocated a Criticality Category of Hazardous has a Software Level of

A

C

B

11. Software changes come under the responsibility of

the national aviation authority

the aircraft constructor

the engineer

12. Software can be modified by

48


using the same rules as apply as to modifications to hardware

the manufacturer

licensed avionics engineers

13. An aircraft system that, should it fail due to a software error, would cause no injuries to occupants, has a criticality category of

minor effect

hazardous effect

major effect

14. What is the effect of a level 1 software failure?

Loss of aircraft and / or fatalities

Significant reduction in safety margins

Large reduction in safety margins

15. Who can sign for a software update?

Design organization or the aircraft manufacturer

Chief pilot

Engineer

16. Software documentation procedures are laid down in

MOE

AWN (45)

JAA Ops

17. Level 1 software failure

is defined as essential and will reduce safety margins

is defined as critical and can lead to loss of aircraft

is defined as essential and may have a minor effect

18. Who can design new software?

BCAR section A8 approved company

BCAR section A1 approved company

The CAA

19. Requirements for configuration management of software can be found in

ATA Chapter 46, Information Systems

AWN 43

JAR Ops (M)

49


20. AWN 43 requires that

the CAA be responsible for software assessment

the aircraft operator be responsible for software assessment

the aircraft constructors be responsible for software assessment

21. Where would you find the rules regarding upgrade of software?

JAR OPS

AWN 43

The aircraft manufacturer

22. Control of software is carried out by

the aircraft manufacturers

the National Aviation Authority

a licensed engineer

Electromagnetic Environment

1. When carrying out airframe bonding checks as part of a programme of HIRF prevention the airframe bonding resistance should be less than

50 milliohms

1 ohm

100 milliohms

2. To shield a fibre optic from EMI you must

shield it with a braided shield

use an opto-isolator

earth both transducer and couplings

3. HIRF is acronym for

Heavily Ionised Radio Frequencies

High Intensity Radiated Field

High Intensity Radio Frequencies

4. When clamping cable looms containing co-axial cables

distortion of the outer sheath is allowed providing the inner cable is not affected

the clamps must be no more than 1 metre apart

avoid distortion to the co-axial cable to maintain the dielectric constant

50


5. Electromagnetic compatibility is achieved by

shielding, screening, earthing, bonding and interference filters

enclosing the system with same frequency and strength of which screening is done

coating in a conductive paint

6. To reduce HIRF on radio equipment

periodically check bonding leads for condition

transmit on all radio frequencies to determine which frequencies are causing the interference

ensure all static wicks are in place

7. Manufacturers of aircraft can ensure HIRF protection

by advising the operator of parts of the aircraft susceptible to degradation due to corrosion, moisture ingress, flexing etc.

by designing specific avionic areas that are shielded against HIRF

by ensuring all single wires are shielded with metal conduit

8. Ribbon cables effected by mutual impedance and current loop leakage should be protected by

connecting all conductors to a common earth

earthing each alternative conductor to separate point

shielding each individual conductor

9. To stop earth loops forming, you would

earth both ends of the cable screen

earth only one end of the cable screen

leave both ends of the cable screen open circuit

10. When incorporating an aerial cable it must be

in the centre of the other wires

outside the other wires for easy access

positioned separately from the loom

11. Testing of HIRF on aircraft systems is done

at and during production and testing (initial certification)

only after a report of radio interference

by periodically listening for interference on all systems

12. For braided cables, the amount of braiding

is a trade-off design feature

must conform to the requirement for the shielding to cover at least 50% of the surface of the cable

51


keeps radiated power inside the emitting assembly or away from the susceptible circuit

13. When carrying out a bonding check on a surface protected by anodic film

the film is conductive so no preparations are required

the anodic film should be removed locally to ensure a good contact

add a bonding factor to the result of the test to account for the resistance of the anodic film

14. HF aerials are protected against lightning strike by

bus terminal

spark gap

current mode coupler

15. Which of the following could be a primary cause of HIRF protection failure?

Unserviceable radio filters

Corrosion on bonding leads

Broken or missing static wicks

16. HIRF protection of LRUs is provided by

built in filters and overvoltage circuits

internally shielded cables

built in filters only

17. An aircraft may have been HIRF affected.

A static wick check is required

Test all radio frequencies for interference

A bonding load check is required

18. In order to maintain HIRF protection, bonding checks between airframe and electrical components carrying voltages greater than 50 volts RMS or DC or main earth return should not exceed

0.05 ohm

1 ohm

1 megohm

Typical Electronic/Digital Aircraft Systems

1. An FMS system, besides controlling navigation, thrust and auto-nav, also provides

GPWS warnings

dedicated status and warnings The FMS is not used for Take Off or Landing The GPWS warnings come from the GPWS Computer

52


take-off and landing warnings

2. The minimum standards for aircraft instrumentation is set by

ICAO

CAA

JAA

3. Testing of a CADC can be carried out

in the air only

on the ground only

in the air and on the ground

4. EADI sky and ground display is provided by

stroke pulse

synthetic TV signals

raster scan

5. What has the highest priority on an ECAM display?

Engine page

Failure

Door page

6. SIDs data stored in the FMC performance database is

Standard Input Data

Standard Information Departure Services

Standard Instrument Departures

7. A modern EHSI will display the following in MAP mode:

waypoints, ILS frequency, ETA, magnetic heading, WXR display, distance to go

waypoints, WXR display only

waypoints, magnetic heading, WXR display

8. HSI heading is valid if the heading flag is

in view

green

out of view

9. MFD is the abbreviation for

Master flight display

Warning flags 'in view' indicate failure. Normally the only coloured flag used is RED, indicating failure

53


Multi function display

Mandatory flight display

10. A level 'B' alert message in EICAS requires

Timely Action

Prompt Action

Time Available Action

11. The FMS can reset the error that builds up in the IRS by using

VOR, DME, GPS, LOC

VOR and DME only

DME and GPS only

12. A TCAS uses the radar mile definition in its calculations, which is

12.36 microsecond

6.18 microsecond

24.72 microsecond

13. GPS navigation uses a constellation of satellites that is made up of

21 active and 3 spare



14. An IRS is only certifed for alignment up to

+88.45 and -88.45 degrees

+60 and -60 degrees

+78.25 and -78.25 degrees

15. The command bars on an ADI relate to

path being followed

roll indications

path required

16. ECAM has at its heart

a multi function symbol generator

a central maintenance computer

ACARS

17. The glideslope in an ILS provides

54


horizontal directional references

vertical references

vertical references and horizontal directional references

18. The recording medium in an FDR is

copper foil coated with ferrite

magnetic tape coated with ferrite

a high density floppy disc

19. An FMS databank memory is updated

every 365 days

every 28 days

every 32 days

20. The frequency of glideslope transmitter is

328.6 to 335.4 MHz

328.6 to 335.4 Hz

328.6 to 335.4 KHz

21. A strapdown INS has

a solid state accelerometer system

both solid state and normal accelerometer system

moving parts

22. What does the CADC feed?

standby altimeter / machmeter

cabin pressure controller sensor / machmeter / altimeter

Altimeter / FMS / secondary radar

23. Marker beacon receivers have

no control unit as the unit typically turns on when the avionics master switch is activated

two control units: one on captain side and the other on copilot side

one control unit

24. In a Flight Management System (FMS), data is input manually to the computing system through the

Control and Display Unit

Electronic Centralised Aircraft Monitoring control panel

Data Acquisition Unit

55


25. The polled mode in an ACARS

operates only when interrogated by the ground facility

both operates when interrogated by the ground facility and allows the flight crew or airborne equipment to initiate communication

allows the flight crew or airborne equipment to initiate communication

26. In a Global Positioning System (GPS), the number of satellites required to achieve a 3 dimensional fix is

2

3

4

27. ACARS system operates in the frequency range of

121.550 MHz

131.550 KHz

131.550 MHz

28. In a Global Positioning System (GPS), each satellite transmission identifies the satellite using a

pseudo random code

whisper shout method

different channel frequency

29. In a MCDU, the flight deck effect is

the sudden irregular reading causing to an instrument

impact of irregular reading to the flight crew

any EICAS display or discrete annunciator to inform the flight crew of an in-flight fault

30. In a Global Positioning System (GPS) satellites below the Mask Angle are ignored as these may cause

clock errors

range errors

ephemeris errors

31. In an EICAS level C messages are

memos and displayed in white

advisories and displayed in amber or light blue

caution and displayed in white

32. Information required by a Flight Management System (FMS) to function correctly is indicated on the display by

a flashing cursor

56


dashes

boxes

33. The compact mode in a EICAS is used

to show maintenance pages

to show maintenance pages and when one display is inactive

when one display is inactive

34. The four display modes used by the ECAM system are

flight phase, advisory, failure-related, manual

warnings, flightphase, advisories, memos

warnings, cautions, advisories, memos

35. A flight data recorder can obtain information from aircraft instruments

provided there is adequate isolation

provided there is adequate damping

by direct connection to the instruments

36. The inputs and outputs of a CADC are

pitot and static in; altitude, CAS, mach and VS out

pitot in; static, altitude, mach, CAS and VS out

pitot and static in; altitude, attitude, CAS and VS out

37. EICAS provides the following:

Engine parameters and system warnings only

Engine parameters only

Engine parameters and engine warnings only

38. A central maintenance computer provides

ground and flight monitoring and testing on an on-board computer

ground and BITE testing using a portable control panel

display of system warnings and cautions

39. The rising runway is positioned from information derived from

radio altimeter

vertical speed

barometric height

40. Where are the Digital Flight Data Recorder outputs supplied to?

57


The recording unit

There are no outputs

Flight instruments

41. FMS failure and warnings are

engine warnings only

displayed on EICAS

EFIS warnings only

42. Flight director command bars are moved to the correct position by

amplifier gain

position feedback

calibration

43. What information is required before completion of the alignment of an Inertial Navigation System?

Heading and attitude

Aircraft present position

Aircraft present position and heading

44. IRS accelerometers are mounted

90° to each other

60° to each other

45° to each other

45. An FMS navigation database is updated

at the operators request

once a month

every 28 days

46. A single failure of a fly-by-wire system

will reduce operational heights and speeds

will limit the flight profile

has no effect on aircraft operation

47. Fly-by-wire load alleviation function in turbulent conditions will result in

spoilers moving symmetrically upwards

ailerons moving symmetrically upwards

ailerons and spoilers moving symmetrically upwards

58


48. Fly-by-wire roll control is achieved by

spoilers

spoilers and ailerons

ailerons

49. The movement of fly-by-wire control surfaces are

both electrically controlled and electrically actuated

hydraulically controlled and electrically actuated

electrically controlled and hydraulically actuated

50. If an EFIS has 3 symbol generators. What is the purpose of the 3rd symbol generator?

Comparison with No.1 symbol generator

Parity function

Standby

51. An FDR fitted to a helicopter begins recording

when power is applied to the aircraft

on engine start-up

on take-off

52. The FMS databases consist of

two performance and one navigation database

one navigation and one performance database

one performance and two navigation databases

53. The FMS can update the IRS position outputs by using information from either

VOR and DME only

DME and GPS only

GPS, DME, LOC and VOR

54. The accepted error from INS/IRS is

1 mile/hour + 3 miles

2 miles per hour + 3 miles

3 miles / hour + 3 miles

55. Before an IRS can complete the alignment sequence

the current present position must be entered

the shutdown present position must be entered

Normally we consider the FMS as having 2 databases (1 navigational and 1 performance). (Jeppesen Avionics Fundamentals Page 385). However, the Navigational database is split in two. 1 is for Jeppesen data, uploaded on the ground, the other is for pilot input data (additional waypoints etc.)

59


either the last or current position must be entered

56. What warnings can an FMS provide?

Ground faults only

Spurious faults

Discrete warnings

57. Electronic Centralised Aircraft Monitoring System

performs in-flight BITE interrogation only

give red warnings and amber cautions to display system status

performs in-flight and ground tests of aircraft systems by carrying out a BITE interrogation

58. The control of the speed or rate that the flight director command bars move can be controlled by

rate or velocity feedback

position feedback

amplifier gain

59. The Centralised Aircraft Monitoring System uses the maintenance mode of operation

either in the air or on the ground

in the air only

on the ground only

60. The third EFIS Symbol Generator is operated

in an emergency

with EICAS

as a standby to the No1 and No2 system

61. EFIS displays of the right hand and left hand displays are compared by comparators in the

FMS

EICAS

Symbol Generators

62. What is the approximate earth rate?

5°/hour

15°/hour

10°/hour

63. An IRS has

two or three accelerometers depending on the system

This means it can warn of inoperative equipment, but not when equipment is providing incorrect data

60


two accelerometers

three accelerometers

64. IRS Laser Ring Gyros provide

rate of movement about an axis

displacement about an axis

both rate and displacement about an axis

65. What are the outputs of a Digital ADC?

TAS, MACH, Altitude, TAT and SAT

TAS, MACH and Altitude

TAS, MACH, Altitude and TAT

66. Fly By Wire systems in the fully active mode, the actuators will

one in active mode, one in damping mode

both be active

both be in damping mode, awaiting control inputs

67. On a Fly By Wire system, what controls the stab trim?

SEC

ELAC

ELAC and SEC

68. The minimum requirement for a cockpit voice recorder to begin operating is

on commencing the takeoff roll

once established in the en-route climb

on engine start-up

69. Aircraft Communications Addressing and Reporting Systems is used to

download aircraft status reports

make telephone calls

allow the pilot of an aircraft to talk to base

70. B-RNAV system must be capable of

reversing the waypoints for return journey

displaying distance and bearing to waypoint

holding six waypoints

71. The basic principle of radar is based upon

Ref to B777 and A330 manuals, the term active mode will always be associated with fully operational of redundancy of all actuators or servo controls. This means, each primary flight control surfaces' actuators (either 2 or 3 actuators configuration designed to provide fully-powered controls that suit the size and purpose of surfaces) are actually active on all phases. If any failure occurs, the failed actuator will then revert to 'damping' mode, becoming slave to remaining active actuators.

JAR Ops states that the CVR must begin when the aircraft is capable of moving under its own power.

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ultrasonic wave propagation

the time delay between outward and returning pulse

the amount of power in the signal returned

72. What systems does the ADC feed?

Standby altimeter/machmeter

Altimeter / FMS / secondary radar

Cabin pressure controller sensor / machmeter / Altimeter

73. Which systems does a modern ADC give information to?

Flight control computer, Air Data Instrument, Engine systems

EICAS

EFIS

74. Where do the outputs from a DADC go?

IRMP: Inertial Reference Mode Panel

EHSI

EADI

75. How many satellite signals are required to achieve precise 3D positioning?

5

4

6

76. The minimum requirement for an aeroplane CVR is

from engine start

from beginning of take off roll

from power on

77. The minimum requirement for an aeroplane CVR is

prior to engine start

prior to power on

prior to beginning of take off roll

78. The difference between the right ADC (air data computer) and the left ADC is encoded in the

label Field

SDI field

SSM field

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79. In a typical EFIS (Electronic Flight Instrument System)

three symbol generators are used to supply the four displays with the correct signals

two waveform generators are used to supply all displays with the appropriate signals

four symbol generators are used to supply the display panels with information

80. If colour distortion appears around the edges of an EFIS (Electronic Flight Instrument System) display, the

CRT (Cathode Ray Tube) has become magnetised

CRT's degaussing circuits are operating continuously

display panel's luminance circuits are at fault

81. An Inertial Navigation System (INS/IRS) computes distance from acceleration by

two successive integrations

a differentiation followed by an integration

a simple integration

82. Before the aircraft is moved from the loading pier the pilot must

insert the longitude and latitude of the first waypoint into the INS

set the altitude to be fed into the INS

insert the latitude and longitude of the pier into the IRS

83. An IRS has

accelerometers fixed to the airframe and gyros on a stable platform

accelerometers and gyros fixed to a the airframe

accelerometers on a stable platform and gyros fixed to the airframe

84. An IRS system requires data for wind computation from

central Air Data Computer

satellites

Doppler System

85. The FMS carries out a Rho/Theta navigation function, the purpose of this is to

update the FMS with the new lateral flight profile for the flight plan

update the VOR and DME systems with an accurate position fix

update the IRS system with an accurate position fix of latitude and longitude

86. The FMS is updated

by the aircrew by reference to the Tech Log

by an aircraft engineer updating the system either by a magnetic tape or floppy disc

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automatically by update data from the ACARS

87. Pitch Control of a fly by wire system is achieved by

stabilizer and elevator

elevators only

stabilizer only

88. In a fly by wire system, if the pilot control input is derived from a side stick controller:

there will be only control surface feedback to the side stick after a computer failure

there is no control surface feedback to the side stick

control surface feedback is fed to the side stick

89. A basic IRS platform has

2 Accelerometers and 3 laser gyros

3 accelerometers and 2 laser gyros

3 accelerometers and 3 laser gyros

90. What must be entered into the IRS before the aircraft can be moved?

Cruise height

Present position

Flight plan

91. The FMS Operational Database is

needs no update information

updated once a month

is fed with information on aircraft weight, cruise altitude and cost index before take off

92. Control surface feedback is fed back to

the side stick controller only

the Flight Control Computer only

the Flight Control Computer and side stick controller

93. The accelerometer output in an INS/IRS is

integrated once to give distance

integrated twice to give velocity

integrated twice to give distance

94. An INS/IRS Battery Unit provides

standby power only on the ground

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standby power when airborne and on the ground

standby power only whilst in flight

95. If a fly by wire actuator loses hydraulic power the control surface will

remain rigid in the failure position

remain in the failure position but may move due to aerodynamic pressure

automatically move back to the neutral position

96. IRS alignment

takes up to 10 minutes and present position must be entered before alignment.

takes up to 10 minutes and the previous flight shut down present position is used for the alignment

takes up to 10 minutes and the present position can be entered at any time during alignment

97. A fault light appears on the IRS Mode Selector Unit during the alignment sequence. The correct action is

select HDG/STS on the Inertial System Display Unit (ISDU), observe the action code in the right alpha/numeric display

refer to the warning display on the EICAS/ECAM system.

immediately switch off and select the standby system

98. A FMS has a total of how many Databases

4

1

2

99. Fly by wire High Speed protection is

to increase the pitch angle as speed increases

to prevent high speed stall

to prevent tuck under

100. An IRS Laser gyro provides

detection of the earth's gravitational force to establish true north

detection of the earth's rotation to establish true north

detection of the rate of movement about an aircraft axis

101. The left and right cockpit displays

are supplied from the same Symbol Generator

are supplied from separate Symbol Generators at all times

will only be supplied from the same symbol generator when all other symbol generators have failed

102. A single failure of a fly by wire control surface computer will

65


cause the system to revert to an alternate law of operation

cause the system to revert to a direct law of operation

not have any operational effect on the system

103. What are the outputs from digital clocks used for?

Flight data acquisition unit, Flight management computer and Voice recorder

VOR, ILS and DME

Weather radar, TCAS and ACARS

104. A full operation system BITE check will carry out an internal system test that ensures the system meets design requirements and is operational

but will not move the controls

as well as checking full system and will move the controls to their stops

as well as checking full system but will not move the controls to their stops

105. If on a flight deck EFIS system all the displays were missing one bit of information. This is most likely to be

the input sensor bus and display controller

the symbol generator and display

the display controller and symbol generator

106. A centralised monitoring computer system is used

testing systems on the ground only

to test systems in flight and on the ground using a centralised on board control unit

to test system during flight and for BITE test of systems on the ground using a carry on control unit

107. In an EFIS display, the lines, scales, indicator and synoptic are generated by

stroke pulse

synoptic scan

raster scan

108. The method of producing (white) lines for aircraft symbols, V/S scale etc. on an EADI is by

raster scan

trapezoidal input

stroke pulse

109. In modern aircraft, the output from the clock is used

to synchronise the signals on the control bus

to provide a clock pulse for CRT

use of built in test equipment states... 'BITE should exercise the hardware sufficiently to determine if it meets the performance requirements but should not drive it against mechanical stops.'

By elimination, since each display is supplied from a different SG, a fault with one SG would affect only one display.

'The special symbols, characters, letters, vectors and arcs are displayed using the stroke method. The EADI sky/ground ball or EHSI weather radar are displayed

66


to give GMT details to the flight recorder and other systems

110. As a minimum requirement, when must a cockpit voice recorder start recording?

After take off when airborne

On first engine start

From the start of the aircraft take off run

111. The operational database of the FMS may have to be modified in flight

automatically by the DADC

by the pilot

It cannot be modified in flight

112. CADC outputs are

altitude ,vertical speed, angle of attack, TAT, SAT

altitude, vertical speed, IAS, mach no

altitude, vertical speed, TAS, CAS, mach no, SAT, TAT

113. If one EICAS CRT fails

the FMS CDU will display the failed CRT data

the standby CRT will automatically take over

the remaining CRT will display primary EICAS data

114. Variations in light on EFIS displays are compensated for by

manual adjustment by flight crew on EFIS controller

An external light dependant resistor mounted on the flight deck compensating for all displays in a parallel-parallel format

integrated light dependant resistors in the display compensating for each display individual

115. A method used in modern aircraft for reporting in flight faults to an engineering and monitoring ground station is

ACARS

TAWS

TCAS II

116. The self test function on an EFIS system can be tested

in the air and on the ground

in the air only

on the ground only

117. Each of the symbol generator outputs in an EFIS system

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can be displayed on each individual display

can not be interchanged

only no. 2 can be displayed on the no.1

118. BITE tests are inhibited for ground use during

forward motion

gear retraction

take-off

119. Modern aircraft with electronic displays would display information on airframe and engine on which system?

EADI

Flight management system

Electronic centralised aircraft monitoring system (ECAM)

120. The Flight data recorder starts recording

on aircraft roll out from stand

after take off

after the first engine has started

121. Data to flight data recorder can be taken from a communal data bus if

source isolation has been considered

the power is within flight data recorder limits

it goes directly to it

122. A central fault display system should be available through

an easily accessible multifunction control display unit

a central bite test box with clear LED indications

a bite test

123. A flight data recorder should be capable of recording

the last 25 hours of aircraft flight

the last 25 hours of operation

the last 25 hours with engines running

124. BITE for ground use only is switched off

when undercarriage up

when brakes are released

on take-off

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125. During normal functioning of an ECAM system the engine data shown on the Engine/Warning display comes from the

ECAM channel of DMC3

EFIS channel of DMC3

ECAM channel of DMC1

126. Using I.N.S. an aircraft flies

course directed by ground station

great circle route

rhumb line

127. Aircraft heading (HDG) is

the angle between True North and the actual track

the angle between True North and the longitudinal axis of the aircraft

the angle between True North and the desired track

128. For an IRS System to pass the 'Alignment System Performance Test' the

entered present latitude and longitude must agree with the latitude and longitude at last power down

the latitude entered must be within given limits of the latitude computed by IRU

the No 1 and No 2 must both have the same latitude and longitude present position entered

129. Control Display Unit (CDU ) selection of TKE (Track Angle Error), displays

difference in degrees from True North in a clockwise direction from the desired track

distance perpendicular from the selected track

difference in degrees that the aircraft is to the right or left of the desired track

130. In the EICAS system, when is the maintenance mode available?

In flight

Lower screen only - only available on the ground

On the upper and lower screens - only available on the ground

131. On a modern aircraft when are BITE checks carried out?

Only when BITE selected

Continuously when system is in use

After engine shut down

132. In an IN system, the purpose of the stable platform is to

stop the gyros from toppling

provide attitude reference

69


prevent unwanted acceleration affecting the accelerometers

133. An IN system requires data from the

satellites

Doppler system

air data computer

134. XTK (cross track) is the

angle in degrees that the aircraft track is left or right of desired track

perpendicular distance from the desired track

actual track across the earth's surface

135. The output of an INS can be fed to the

attitude indicators

vertical speed indicators

altimeters

136. The three accelerometers on a strapdown system are mounted

120° apart

parallel to each other

90° to each other

137. Gyro-compassing is the term used for

self-alignment in the vertical

use of the gyro-magnetic compass system to align the platform

self-alignment in azimuth

138. Electronic Centralized Aircraft Monitoring System operates to

perform in-flight and ground tests of aircraft systems by carrying out a BITE

give red warnings and amber cautions to display system status

perform in-flight BITE only

139. The Centralized Aircraft Monitoring System uses the maintenance mode of operation

either ground or air

in the air only

on the ground only

140. If part of a display is lost on a CRT, this could be due to

an inoperative symbol generator or control panel

70


an inoperative symbol generator or input sensor

loss of power to the CRT

141. A cyclic test (watch dog) should be performed for ECAM

during power up

during flight

via MCDU

142. How does the symbol generator detect a program error?

By check sum bites for error detect

By looking at the odd parity without error

By looking at the even parity without error

143. Relationship of CMCs to BITE systems is best described as

CMCs replaced but is not related to the older BITE system.

CMCs modifies and upgrades BITE systems

CMCs monitors the individual BITE systems and presents data.

144. An IRU interface test is carried out

in the air

only on the ground

on the ground or in the air

145. FMS system gives warning indications for

take off and landings only

cruise

any flight phase

146. FMS CDU warnings are

MSG, fail and OFST

fail and MSG

OFST and Fail

147. CMC (central maintenance computer) works to

give red warnings and amber cautions to display in accordance with system status

perform in-flight bite only

perform in-flight bite and ground tests of aircraft systems, i.e. BITE

148. BITE test carried out on input sensors and actuators performs

71


validation of the information of the LRU

a test of the LRU

a performance test of the system

149. A BITE check for automatic performance and fault monitoring is carried out when?

For in-flight monitoring

To check the performance of the LRU

Power-up self test

150. In which of the following does TCAS II advise the pilot to make a maneouvre?

RA

TA

either RA or TA

151. What are the shapes of traffic shown on a TCAS display?

White circles, red diamonds and amber squares

White squares, red diamonds and amber circles

White diamonds, red squares and amber circle

152. If a display shows a red cross only, it is due to

Symbol Generator failure

Altimeter failure

CRT failure

153. ACARS is an acronym for

Airborne Communicating Addressing and Reporting System

ARINC Communicating Addressing and Reporting System

Aircraft Communicating Addressing and Reporting System

154. When does the flight data recorder start recording ?

Parking brake released

Undercarriage up

When the first engine starts

155. Brake temperature displayed on a flight deck CRT has

a master warning light

same colour throughout

different colour for different temperatures

72


156. When performing test on Electronic Displays using the Built In Test system

SG injects a test signal into the display system and the word TEST appears on the screen

CRT continues to display current data while the SGs and Display are internally tested

displays cannot be tested it is only SG which are tested by BITE

157. Heading reference required to establish initial heading during alignment sequence comes from

FMS which gathers data from other Radio devices

Magnetic compass installed on the airplane

Earths Rotation

158. What is primary mode of navigation on a modern aeroplane?

Both GPS and IRS

Inch precise GPS

Only IRS

159. In a flight director, how are small deviations corrected?

Instrument is calibrated at fitment to remove any possible error

Instrument feedback

Pilot input

160. For a 3 dimensional fix in a Global Positioning System

Minimum of 4 satellites must be in view

Minimum of 3 satellites must be in view

Minimum of 2 satellites must be in view and altitude used to simulate a 3rd satellite

161. In an aircraft equipped with TCAS II and EFIS

RA pitch command is shown on the EHSI and TA/RA traffic on the EADI

RA pitch command is shown on the EADI and TA/RA traffic on the EHSI

RA pitch command is shown on the VSI and TA/RA traffic on the EHSI

162. The BITE indicator on a DFDR shows Yellow colour. This indicates

power is ON and DFDR is recording data

power is OFF or DFDR is at Fault

power is ON but DFDR is not recording data

163. In a typical 'Glass Cockpit' EICAS provides the following:

engine parameters and engine warnings only

engine warnings only

73


engine parameters and system warnings only

164. What is the minimum requirement for CVR to operate?

BEFORE engine start

BEFORE take-off

at any time the manufacturer decides

165. ECAM system was adopted for

both Boeing and Airbus aircraft

Boeing 757 and 767 aircraft

Airbus A310

166. A modern electromagnetic Flight Data Recorder, for recording data, could use:

a plastic tape coated in ferrite

a copper tape coated in ferrite

a High Density floppy disk

167. What is the minimum requirement for a CVR to start recording?

When parking brake is released

When aircraft is capable of moving under its own power

On commencement of flight

168. As a minimum requirement when must a cockpit voice recorder start recording?

Before engine start

Once airborne after take off

Once aircraft is ready to move under its own power

Unverified

1. ARINC 429 slow speed transmission is

80 microseconds

10 microseconds

10 miliseconds

2. In an ARINC 429 digital data word, the source/destination identifier is made up of two bits positioned at

bits 1-2

bits 9-10

bits 30-31

3. When testing a diode with a test set, what voltage drop would be typical?

74


0.3 - 0.7

1.5 - 2.0

2.5 - 3.0

4. ARINC 429 NULL state is represented by a voltage of

+10V

0V

-5V

5. 26 octal, represented in decimal, is

19

22

010110

6. What is the data stored on within bubble memory?

A disk drive

Ferrite material

Magnetic loops

7. The Flight Management Computer System is updated periodically during flight by

the maintenance monitoring computer

the pilot

pre-loaded hard data

8. The aircraft clocks send signals to aircraft systems to

display/record Greenwich Mean Time

set computer clock speed

coordinate system operation

Type Distinctive shape

Rectangular shape Boolean algebra between A & B

Truth table

AND

A.B INPUT OUTPUT A B A AND B 0 0 0 0 1 0 1 0 0

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75


1 1 1

OR

A+B INPUT OUTPUT A B A OR B 0 0 0 0 1 1 1 0 1 1 1 1

NOT

_ A

INPUT OUTPUT A NOT A 0 1 1 0

NAND

___ A.B

INPUT OUTPUT

A B A NAND B

0 0 1 0 1 1 1 0 1 1 1 0

NOR

___ A+B

INPUT OUTPUT A B A NOR B 0 0 1 0 1 0 1 0 0 1 1 0

XOR

INPUT OUTPUT A B A XOR B 0 0 0 0 1 1 1 0 1 1 1 0

XNOR

INPUT OUTPUT

A B A XNOR B

0 0 1 0 1 0 1 0 0 1 1 1

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Module 5

Documents

display control

flight director information

system electronic indicator

aircraft symbol

efis adi display

flight director bars

control alerting system

efis system adi