Originally Posted by
Check Airman
Hi all,
1- we’re usually taught that when changing a value (not mode) on the FCU/MCP, to verify that the new value is reflected on the PFD, and not just the FCU. Has anyone ever seen a situation where the PFD and FCU values are different?
I had this just the other day. While Changing the BARO QNH setting with the selector on the FCU, the value in the FCU window didn’t change but the value on the PFD did (including a corresponding change in altitude indicated).
A basic Airbus principle is to look for the output rather than rely on the input. If you try to switch your kitchen light on you check that the bulb has illuminated rather than relying on the switch position alone.