Electronic Instrumentation — Page 540, Lesson 645

I want to walk you through the world of electronic instrumentation for engine and airframe systems control. This is where we move away from the traditional round dials and gauges, and into the world of screens and displays. First, let's establish the foundation. The parameters associated with engine performance and airframe systems control are now displayed using Cathode Ray Tube, or CRT, or LCD type displays. CRT is the older technology, like the big heavy televisions, and LCD is the flat-screen technology. These have become a standard feature on many types of aircraft, just as they have for flight instrument systems. Now, these display units are not just random screens. They form part of two principal systems. The first is the Engine Indicating and Crew Alerting System, which we call EICAS. The second is the Electronic Centralized Aircraft Monitoring system, which we call ECAM. These are the two big names you need to know. Here's an important piece of history. EICAS was first introduced on the Boeing 757 and 767 aircraft. ECAM was first introduced on the Airbus A310. So we have Boeing with EICAS, and Airbus with ECAM. Now, when these systems were first introduced, there were differing views in the industry on how to approach several operating factors. Let me list them for you. There were questions about flight deck layouts and how the crews would control functions. There were questions about the extent to which normal, alerting, and warning information should be displayed. And in particular, there was a big debate about whether engine operating data needed to be displayed for the whole of a flight, or only at various phases of the flight. This philosophical difference is what really separates EICAS from ECAM. Let's look at EICAS first. In respect of EICAS, engine operating data is displayed on screens. This eliminates the need for traditional instruments. So on a Boeing 757 or 767, you don't have the old-fashioned engine gauges. It's all on the screen. Now, here's a key point about EICAS. This data, as well as data relevant to other systems, is not necessarily always on display. The screen might not show everything all the time. But in the event of malfunctions occurring at any time, the flight crew's attention is drawn to them by an automatic display of messages in the appropriate colours. So if something goes wrong, the system automatically pops up a message on the screen, and the colour of that message tells you the severity. That's the alerting function of EICAS. Now, ECAM is different. The ECAM system displays systems' operation in checklist and schematic form. So instead of just numbers and messages, you get a checklist and a schematic diagram of the system. This was a concept based on the view that engine data needed to be displayed during the whole of a flight. Because of that view, traditional instruments were retained in the Airbus A310. So the A310 kept its conventional engine gauges, and the ECAM screens were added on top of that. Now, here's an interesting note. In subsequent types produced by this manufacturer, for example the A320, the ECAM system is developed to include... and that's where our excerpt ends. So we'll pick that thought up next time. Let me just make sure the key contrasts are clear in your mind. EICAS, on Boeing, displays engine data on screens and eliminates traditional instruments. It only shows data when needed, and alerts the crew with coloured messages on malfunction. ECAM, on Airbus, displays systems in checklist and schematic form, was based on the philosophy that engine data should be shown for the whole flight, and so the A310 kept its traditional instruments alongside the ECAM displays. That's the core of this passage. The two systems, their manufacturers, their philosophies, and their differences.