11.18 On Board Maintenance Systems

Question 1

What is the purpose of central maintenance computer system (CMCS)?

Answer 1

Provides a central location in cockpit for trouble shooting with test and fail reporting

Question 2

What does CMCS stand for?

Answer 2

Central maintenance computer system

Question 3

How many CMC ( central maintenance computers) are there on an aircraft?

Answer 3

2 in avionics compartment
1 running at a time

Question 4

How many multi purpose control and display units (MCDU) are there?

Answer 4

Two or three

Question 5

What two modes does the CMCs have?

Answer 5

. Reporting mode
. Interactive mode

Question 6

What is reporting mode capable of?

Answer 6

Active during flight
Scans all connected aircraft systems and memorises any faults

Question 7

Any faults found on reporting mode can be printed or displayed or…?

Answer 7

Sent via the data- link system (ACARS( to home base)

Question 8

When in interactive mode what is it capable of?

Answer 8

Used for functional checks and fault investigation

Question 9

When can interactive mode be selected?

Answer 9

Only selected on ground

Question 10

What does BITE stand for?

Answer 10

Built in test equipment

Question 11

What two functions does BITE have?

Answer 11

. Detects failures
. Perform system tests on ground

Question 12

What is the MCDU in conjunction to CMCS?

Answer 12

MCDU is the main interface to CMCS

Question 13

What does FAIL annunciation show?

Answer 13

That the MCDU is defective and another MCDU must be used

Question 14

How many characters across an MCDU display?

Answer 14

24 characters across

Question 15

How many lines of MCDU display?

Answer 15

14 lines

Question 16

What shows that a printer is available?

Answer 16

• atriks

Question 17

What control keys are used to switch from page to page on MCDU?

Answer 17

. Down arrow = next page key

. Up arrow = previous page key

Question 18

What are two ways CMCS can report to two different interface functions?

Answer 18

. Printer
. ACARS - Data link to home base

Question 19

What would the printer show if it doesn’t work?

Answer 19

NO RESPONSE message

Question 20

When sending a report by ACARS what are the two messages it will show?

Answer 20

. Transmission in progress
. Transmission complete

Question 21

What does the * mean for a printer?

Answer 21

Shows that function can be started
(Printer works)

Question 22

What is the post flight report?

Answer 22

The report from the last flight leg

Question 23

What 3 things does a does fault message display?

Answer 23

. Line replacement unit
. Equipment code
. ATA chapter number

Question 24

What is hard faliure?

Answer 24

A permanent faliure

Question 25

What is intermittent faliure?

Answer 25

Can occur once or several times during flight, but not reported after flight

Question 26

How many faults can be stored in the electronic library system (ELS)?

Answer 26

Up to 500

Question 27

Faults are only stored when they occur in what phase?

Answer 27

Flight phase

Question 28

What three ground tests are available?

Answer 28

. System test
. Complementary test
. Output test

Question 29

How many days just the flight management system (FMS) data base be updated?

Answer 29

Every 28 days

Question 30

What is the earliest form of structure monitoring?

Answer 30

Fatigue meter