EFIS & Glass Cockpits

Back in the 1980’s when the first ‘glass’ instrumentation was being introduced, it was known as ‘EFIS’, not ‘glass’. EFIS refers to Electronic Flight Information Systems. Technology had advanced to the point where information that been previously displayed via electromechanical instrumentation, could now be displayed electronically, and one instrument was now capable of displaying much more information, in color! A major improvement!

I had my introduction to ‘EFIS’ when I transitioned from the Swearingen Metroliner, to the ATR-42, which was a brand new turbo-prop, in 1987. The ATR was built in France, by the French aerospace company Aerospatiale (now Airbus). It had 42 passenger seats, thus the ‘-42’ in the name. Other major improvements over the Metroliner; the ATR-42 is considerably larger, it is operated under the more stringent FAR 25, and because it has more than 19 seats, a Flight Attendant is required.

The EFIS back then was quite simple by today’s standards and typically consisted of only four ‘tubes’ or CRT (cathode ray tube) displays. They were, the pilot’s ADI (attitude deviation indicator) and HSI (horizontal situation indicator), as two separate instruments/displays. The co-pilot (F/O) also had the same ADI and HSI on his/her side.

Today the ADI and HSI are combined into one instrument, now called the PFD (Primary Flight Display). Both sides have a PFD. And now in the center, between the pilots is an MFD, or Multi-Function Display, which might have navigation information displayed on it. And the CRT’s have been replaced by LCD (liquid crystal display) screens. Much progress has been made with this. And now the displays are considerably larger. Now the older ‘six pack’ of six flight instruments has been replaced by two large displays, the PFD on the pilot’s side and another PFD/MFD on the co-pilots side. Some aircraft have three displays, with two PFD’s and one MFD in the center. It varies by aircraft.

When I transitioned again from the ATR-42 to the EMB-120 Brasilia, another turbo-prop, it also had a 5 ‘tube’ EFIS. Each pilot had a glass ADI/HSI, and there was an MFD in the center. And for both the ATR and the EMB-120, in the event of a failure or malfunction of an EFIS display, a composite mode was available as a back-up. The composite mode combined two displays into one, so a pilot would still have the pitch & bank information in the top half of the display, along with the navigation information on the bottom of the display. Or, information from a PFD could also be transferred or displayed on the MFD in the center.

And now ‘glass cockpits’ are not limited to airliner cockpits. Now all corporate jets (large and small) have ‘glass cockpits’ as do most general aviation piston and turbo-prop aircraft. This occurred in general aviation about fifteen years ago, in 2003 and 2004. Cirrus Aircraft installed an Avidyne PFD in their SR20 and SR22 back in 2003. Garmin, a leading manufacturer of avionics and ‘glass cockpits’, delivered the first G1000 in a Diamond DA40 in June 2004. Shortly after this, Cessna installed the first G1000’s in their 182 in July 2004. Cessna began shipping their 172 in early 2005. Now, all aircraft manufacturers are installing some version of the ‘glass’ cockpit. It’s here to stay!