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On-board warning system

Historically, the first on-board warning system was the pilot. Pilots had to manually scan and periodically check each system on the overhead panel and on the instruments in the cockpit. It did not take long to notice the inherent limitations of the pilot’s abilities in abnormal situations. Malfunctions/failures may be overlooked or misinterpreted, particularly in critical situations where stress, time constraints and high workload are involved.

Thus was born the development of on-board warning systems, to which we will later on associate the CAS or the Crew Alerting System messages.

CAS is an electronic system integrated in modern airliners, including more and more general aviation aircrafts. They monitor various aircraft systems and alert the pilots whenever a malfunction is detected.

In early generation aircrafts, warning systems were not fully integrated. There was not a central unit watching over all the systems. Warning lights and sounds were dispatched all over the flight deck for each instrument/systems, which can also lead to misinterpretation, or often, preclude the pilot from seeing the big picture.

Various improvements were made over the years, such as the integration of a master annunciator panel and master warning/caution lights. A single sound or light would alert the crew of the malfunction, who will then check the annunciator panel, which regroup individually labeled, color-coded lights indicating the source of the failure.

In the last recent years, designers took the on-board waning system technology to a whole new level, creating the CAS (Crew Alerting System), also called ECAM for Airbus (Electronic Centralized Aircraft Monitor) and EICAS for Boeing (Engine Indicting Crew Alerting System).

CAS (Crew Alerting System), How does it work?

The CAS generates different kinds of aural, visual and tactile cues that draw the attention to situations that a crew/pilot should be aware of. The CAS is able to monitor hundreds of engine and aircraft system parameters. It provides three different level of information: Advisories, Cautions and Warnings.

Similarly to CAS, a Master Warning/Caution will illuminate to get the pilot’s attention. Depending on the situation or specific systems, different sounds will be emitted. A color-coded message indicating the exact failure is then sent to the screen display of the pilot. Additionally, the ability of the system will also guide the pilot with the checklist to be carried out, and in some type of aircrafts, the checklist actions required to deal with malfunction/failures, meaning pilots have greater flexibility to concentrate on the “big picture” while managing potentially complex situations.

And if two or more conditions are detected simultaneously, CAS will present the checklists to be carried out in a predetermined priority sequence.

CAS messages, unique CHECKL!ST feature

To keep up and updated with the fast modernization of aircraft technology and CAS, our team has integrated, in the CHECKL!ST App, a unique feature designed towards your needs.

As more and more general aviation aircrafts are using various kinds of CAS system, our goal was to offer digital checklists adapted for all type of users and aircrafts.

Whenever a CAS message is associated to a certain checklist and pops up on your display, not only can you easily retrieve it in our Emergencies page, but we designed the feature in the same manner and color-coding scheme as the manuals from the manufacturer. Should there be differences in the design or checklists, not an issue, we made sure they are all customizable. You will either find the type of CAS of your current cockpit, create a custom CAS, or a combination of both, to match your needs.

In our upcoming article, we will dive into all the customizable items the app has to offer, but don’t hesitate do download the app and check out the User’s manual.

Fly safer with our electronic checklist!

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