Evolution Of Aircraft Alarm and Warning Signals

As aircraft have grown more complex over the decades, it is inevitable that their warning systems have become more complex as well. If a malfunction or error occurs, the pilot or pilots need to be informed, after all. But in the early years of aviation, these warning systems were haphazardly scattered throughout the cockpit, often with no indication of a problem’s severity.

To bring some order to this chaos, designers began adding a master annunciator panel to the aircraft’s cockpit. If a fault or error of any kind is detected, a prominent light will turn on in the cockpit, which then draws the crew’s attention to the master annunciator panel. On this panel, individually labeled and color-coded lights indicate the exact problem or its severity. Typically, red will be used for serious problems that require immediate action from the crew. Orange/amber-colored lights are for issues that require crew awareness, but not necessarily an immediate reaction. Finally, blue lights, or advisory or agreement lights, are there to let the crew know that something is working as intended (such as de-icing equipment or fuel crossfeed valves) and to remind the crew to turn that system off when it is no longer needed.

Later-generation turbine aircraft take advantage of modern technology to update their warning systems to the 21st century. Boeing’s 777, for instance, uses a Crew Alerting System (CAS) that integrates multiple kinds of visual, audio, and tactile cues to draw attention to various situations. An important part of the CAS is the Engine Indication and Crew Alerting System, or EICAS. The CAS will first try to get the crew’s attention by turning on master caution or warning lights on either side of the forward instrument panel, as well as making a beeping noise, sound a bell or siren, or generate a voice message. At the same time, a text message will display in the EICAS display screen, located in the center of the instrument panel, which describes the condition, such as Fire Engine R to indicate a fire detected in the right engine. These messages always correspond with the titles of the emergency checklist needed to handle the situation. CAS can also determine the severity of multiple malfunctions or issues and decide which needs the most attention at the moment

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1. craig lewis
2. Posted on July 9, 2019
aviation

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