In a dual autopilot configuration, with AP1 and AP2 active, which statement is true about signal sources to autopilots?

In a dual autopilot configuration, with AP1 and AP2 active, which statement is true about signal sources to autopilots?

• A. Autopilots receive signals from both FMGCs
• B. Autopilots receive signals from FMGC 1 only
• C. Autopilots receive no FMGC signals
• D. Autopilots receive signals from FMGC 2 only

Answer: (A)

Redundancy in signal sources to autopilots means both FMGCs feed AP1 and AP2. The flight guidance commands that steer the aircraft come from the FMGCs, and in a dual autopilot setup these data streams are provided to both autopilots, allowing either AP to use guidance from either FMGC. This setup lets the system continue to provide valid commands if one FMGC or its path fails, and it also allows cross-checking between the two sources for consistency. Feeding only one FMGC would create a single point of failure, and there will still be FMGC input to the autopilots under normal operation.

Redundancy in signal sources to autopilots means both FMGCs feed AP1 and AP2. The flight guidance commands that steer the aircraft come from the FMGCs, and in a dual autopilot setup these data streams are provided to both autopilots, allowing either AP to use guidance from either FMGC. This setup lets the system continue to provide valid commands if one FMGC or its path fails, and it also allows cross-checking between the two sources for consistency. Feeding only one FMGC would create a single point of failure, and there will still be FMGC input to the autopilots under normal operation.