When does the MFD switch to essential mode automatically?

• A. When power is lost
• B. If the PFD is lost
• C. When the autopilot is engaged
• D. When landing gear is deployed

Answer: (B)

The correct understanding lies in recognizing that the Multi-Function Display (MFD) switches to essential mode automatically if the Primary Flight Display (PFD) is lost. In essential mode, the MFD prioritizes the most critical information needed for flight safety and navigation purposes, ensuring that pilots can still operate the aircraft effectively without the PFD.

This functionality is built into the systems design to enhance redundancy and safety, providing necessary data even when there is a failure in the primary display system. Thus, the MFD's response in this scenario is a crucial design feature aimed at maintaining operational integrity despite potential component failures.

The other scenarios presented do not trigger the MFD to switch to essential mode automatically, as those conditions involve different system behaviors and priorities.