MCDU / FMGS

Question 1

What are the main components of the FMGS?

Answer 1

• 2 FMGC’s
• 2 MCDU’s
• 1 FCU
• 2 FAC’s

Question 2

What are the functions of the Flight Management Guidance Computers?

Answer 2

• Flight Guidance

* Flight Management

Question 3

What are the 3 modes of FMGC operation?

Answer 3

• Independent
• Single
• Dual
• Nav Backup

Question 4

What are the 2 modes of flight guidance?

Answer 4

• Managed Guidance

* Selected Guidance

Question 5

What is the Managed mode of flight guidance used for?

Answer 5

Long-term lateral, vertical, and speed profiles as determined by the FMGS

Question 6

What is the selected mode of flight guidance used for?

Answer 6

Temporary lateral, vertical, and speed commands as selected with the FCU.

Question 7

Does Selected or Managed Guidance have priority?

Answer 7

Selected Guidance

Question 8

What type of database is periodically updated in the FMGS?

Answer 8

Navigation database

Question 9

Can the crew modify data in the navigation database?

Answer 9

The crew has limited ability to create pilot stored navigational data.

Question 10

How do you determine the validity of the navigation database?

Answer 10

On the Aircraft Status page

Question 11

What input does each FMGC use for position determination?

Answer 11

A hybrid IRS/GPS position

Question 12

What is the normal operational mode of the FMGS?

Answer 12

Dual mode, with one FMGS as master and the other FMGS as slave

Question 13

How does autopilot selection influence master FMGS logic?

Answer 13

• If one autopilot is engaged, the respective FMGS is master
• If both autopilots are engaged, FMGS 1 will be the master
• If no AP/FD is engaged, A/THR is controlled by FMGC 1
• If no AP is engaged:
FD1 is on, then FMGC 1 is master
FD 1 off & FD2 on, then FMGC 2 is master

Question 14

If amber OFF SIDE FM CONTROL message is displayed on the ND what action should the crew
take?

Answer 14

An FMGS has failed and both ND’s must be set to the same mode and range

Question 15

Can both autopilots be engaged during any phase of flight?

Answer 15

No, only during an ILS approach

Question 16

What is the difference between the large and small fonts utilized in the MCDU?

Answer 16

• Large – Pilot entries and modifiable data

* Small – Default/computed non-modifiable data

Question 17

When would a Takeoff Shift be entered on the PERF TO page?

Answer 17

When takeoff begins at a runway intersection.

Question 18

If the FLEX TEMP is not entered on the TAKEOFF page of the MCDU, and the thrust levers are
positioned in the FLEX detent, what will occur?

Answer 18

• A warning will be generated

* Continue to move the thrust levers to the TOGA detent and execute a max thrust takeoff

Question 19

Where do you enter the Zero Fuel Weight?

Answer 19

INIT B Pages

Question 20

What do amber box prompts on the MCDU indicate?

Answer 20

An entry is mandatory.

Question 21

What occurs when managed NAV mode is engaged and the aircraft flies into a flight plan
discontinuity?

Answer 21

NAV mode will be lost and the HDG/TRK mode engages.