Definition

A Multifunction Display (MFD) is a standard element in an Electronic Flight Instrument System (EFIS), commonly known as the "glass cockpit" system found in modern aircraft. The MFD can display navigational information such as a moving chart display, or it can show other information such as systems status.

Description

In most EFIS systems, both the pilot and the copilot have a dedicated Primary Flight Display (PFD) and an MFD on their panels. Typically, an EFIS system also includes an Engine Indicating and Crew Alerting System (EICAS) screen in the center of the main panel. In normal operation, the PFD displays aircraft attitude, altitude, speed, vertical velocity, etc., and the MFD is typically used to display navigational information. However, the MFD can also display a variety of other information through the use of pushbuttons or selections made by touchscreen or with a cursor. In most MFD installations, the screen can show synoptic pages that display the status of various systems such as electrics, hydraulics, pressurization, environmental, etc.

The MFD can also serve as a backup for the PFD and EICAS screens. For example, if a pilot's PFD screen fails, the MFD can revert to display PFD information. Depending on the model, this reversion can be made automatically or through the use of reversionary switches. Most models will also allow an MFD to display EICAS information if the normal EICAS screen fails.