A320 Navigation Questions

While taxiing on the ground, the FMGS displays the position of the aircraft using:

• IRS and DME/DME.
• IRS only.
• IRS and VOR/DME.
• DME/DME and VOR/DME.

Explanation: The FM position update priority runs IRS-GPS, then IRS-DME/DME, then IRS-VOR/DME, then IRS only - while taxiing on the ground, before any of those radio/GPS updates are established, the FMGS is working from IRS data alone.

Auto Flight - Flight Management (Navigation - Position Computation)

With the autopilot engaged, either sidestick can be moved freely.

• True.
• False, moving either sidestick will cause the autopilot(s) to disengage
• False, only the PNF’s sidestick will freely move.

Explanation: False - with the autopilot engaged, moving either sidestick causes the autopilot to disengage (it isn't free to move without consequence).

Flight Controls - General (Sidestick / Autopilot Interaction)

How does the FMGS derive Vapp?

• Vapp=Vls+5+(1/3 surface headwind component).
• Vapp=Vls+10+1/3 surface headwind component.
• Vapp=Vls+5+1/2 surface headwind component.
• Vapp=Vls+10+1/2 surface headwind component.

Explanation: The FMGS derives VAPP as VLS + 5 + one third of the surface headwind component.

Auto Flight - Flight Management (Approach Speed Computation)

What is managed climb speed below 10,000 feet?

• Green dot.
• 210 knots.
• 250 knots.
• Best rate of climb speed.

Explanation: Managed climb speed below 10,000 ft is normally limited to 250 knots (the FMGS speed limit default for that altitude band).

Auto Flight - Flight Management (Managed Speed Profile)

The airspeed indication on the PFD starts at:

• 100 kts.
• 80 kts
• 50 kts.
• 30 kts

Explanation: The airspeed indication on the PFD's speed scale starts at 30 kt.

Indicating - PFD (Speed Scale)

When the aircraft is in the Managed Guidance mode, it is:

• Guided by the pilot selecting the specific flight modes and parameter target values on the FCU.
• Responding to pilot inputs of speed, altitude, and heading selected on the FCU.
• Following lateral, vertical and speed profiles as determined by the IRS’S.
• Following lateral, vertical and speed profiles as determined by the FMGS.

Explanation: In Managed Guidance, the aircraft follows the lateral, vertical, and speed profiles computed by the FMGS - as opposed to Selected Guidance, which follows pilot-set FCU targets.

Auto Flight - General (Managed and Selected Guidance)

Can the crew depress the RMP ON NAV pushbutton and use the RMP for navigation simultaneously with FMGC autotuning?

• Yes, because the opposite FMGC will continue to autotune navaids.
• No, RMP backup tuning supersedes the autotuning function of both FMGC’s.

Explanation: No - selecting an RMP for backup radio tuning is a manual override, and it supersedes the FMGC's automatic autotuning function on that radio rather than running alongside it.

Auto Flight - Flight Management (Navigation - Radio Navigation Tuning, RMP Backup Mode)

SRS will command:

• V2 + 10 with both engines operating.
• V2 or current aircraft speed (whichever is higher) in the case of an engine failure.
• Best rate of climb taking into account actual wind component.

Explanation: In SRS mode with both engines operating, the target speed is V2 + 10 kt (with an engine failure, the target instead becomes the higher of V2 or current speed, capped at V2 + 15 kt).

Auto Flight - Flight Guidance (Speed Reference System, Guidance)