FCOM DSC AUTO FLT NAV ADIRS

Question 1

The FMGS uses the:

Answer 1

reference point coordinates of the departure airport to align the IRS.

Question 2

It calls these up from the:

Answer 2

database automatically after the flight crew has entered a company route or an origin-destination city pair and pressed the ALIGN IRS key on the MCDU.

The flight crew can adjust these coordinates manually to the gate position.

Question 3

A normal alignment takes:

Answer 3

10 min

Question 4

A fast alignment takes:

Answer 4

30 s.

Fast alignment is used to refine a position when time is limited.

Question 5

If the “IRS IN ALIGN” memo flashes on the E/WD during the alignment process, it indicates one of the following:

Answer 5

‐ It has detected excessive motion. (It automatically restarts the alignment)

‐ It has detected a disagreement between the position the MCDU has sent to the IRS, and the last memorized IRS position. The flight crew must enter new coordinates in the MCDU, and realign the IRS

‐ It has detected a disagreement between the latitude the MCDU has sent to the IRS, and the latitude the IRS has computed during the alignment

‐ The IRS has not received a position from the MCDU .