The Engine Indication and Crew Alerting System (EICAS) on the Boeing 767 enhances both aircraft maintenance and operation. It automatically records subsystem data when malfunctions are detected and can also manually record data at the push of a button, thereby reducing manual data logging and increasing data accuracy.
EICAS consists of two computers, two display switching modules, multicolor display units, a display select panel, a maintenance panel, cancel/recall switches, two master caution lights, a signal consolidation card, and an optional maintenance enable bypass switch. These components work in unison to manage EICAS functions.
During normal operations, the EICAS computers process system inputs and manage data displays. Only one computer drives the displays at any time, with the selected output being routed by the display switching modules. Primary engine parameters and alert messages appear on the upper display unit, while secondary engine parameters are shown on the lower unit, which can also be switched to status or maintenance modes.
EICAS minimizes flight crew workload by providing automated systems monitoring and data display from power-up through post-flight maintenance. It assures crew awareness of system status changes with automatic and manual features. Operational displays can be modified using the STATUS and ENGINE switches on the display select panel.
Preflight, EICAS automatically displays all engine parameters to allow for checks like oil quantity before engine start. Post-engine start, it can switch to the status mode for control surface checks. In flight, if a component fails or an abnormal condition arises, EICAS alerts the crew with a “STATUS” indication, prompting them to check the systems and prepare for any necessary maintenance post-landing.
The system offers three display modes:
Operational Mode: At power-up, it shows all engine parameters, with primary parameters like N1 and Exhaust Gas Temperature (EGT) on the upper display, and secondary parameters on the lower display.
Status Mode: Accessed via the display select panel, it provides sub-system parameters and status messages on the lower display.
Maintenance Mode: Activated through the EICAS maintenance panel, it presents sub-system parameters and maintenance messages.
EICAS also highlights parameters that exceed normal ranges with color-coded alerts to draw immediate attention for swift action by the crew.