EFIS — Electronic Flight Instrument System

Overview

EFIS is a flight-instrument display system that shows flight data electronically rather than electromechanically. It replaced the array of individual mechanical gauges in older cockpits with a small number of high-resolution electronic displays, giving rise to the popular term "glass cockpit."

From Steam Gauges to Glass

Traditional cockpits used separate electromechanical instruments - attitude indicator, airspeed indicator, altimeter, heading indicator, vertical speed indicator, and more - each a standalone mechanical gauge, collectively nicknamed "steam gauges." EFIS consolidates this information onto a handful of electronic screens, first using cathode-ray tube (CRT) displays and, from the 1990s-2000s onward, liquid-crystal displays (LCDs).

Core Displays

History

EFIS entered commercial service in the early 1980s. Boeing's 757 and 767 (entering service in 1982) and Airbus's A310 (1983) were among the first airliners delivered with electronic primary flight and navigation displays in place of mechanical instruments. By the late 1980s, EFIS had become standard equipment on new Boeing and Airbus airliners, and business aircraft widely adopted it through the 1990s.

Benefits and Certification

EFIS reduces cockpit clutter and pilot workload, allows flexible reconfiguration if a display fails, and integrates closely with other avionics such as the Flight Management System (FMS), TCAS, and weather radar. Later-generation EFIS adds features like synthetic vision and vertical situation displays. In the United States, design and certification guidance for transport-category electronic displays is set out in FAA Advisory Circular AC 25-11B, "Electronic Flight Displays."

Related Systems

EFIS works closely with the Flight Management System, which drives the lateral and vertical navigation shown on the ND/MFD, and it was introduced alongside fly-by-wire flight control systems on the same generation of aircraft, such as the Airbus A320.