Left Seat

The Garmin GTN 750 touchscreen flight management system

Garmin is all in on touchscreen avionics. It will no longer build its wildly successful GNS 430/530 flight management systems which have been replaced in production by the GTN 700/600 series units that have touchscreen control. Garmin also has the G2000, G3000 and G5000 integrated flat glass systems that span the spectrum from piston single to the fastest business jet all using touchscreen control units.

And Garmin is by no means alone. Avidyne has announced development of touchscreen navigation and flight management control units. So has Bendix/King. And one of the biggest players of all, Rockwell Collins, has added touchscreen capability to its Fusion advanced flat glass avionics system for turbine airplanes.

We’re living in a touchscreen world given the overwhelming acceptance of smart phones, iPads and all manner of personal electronic devices. Even a new refrigerator and clothes dryer has a touchscreen pad to command its operation. Why would aviation not join in the touchscreen revolution.

Garmin was first to market with an installed and certified touchscreen system when it introduced the GTN 750/650 about a year ago. Garmin had been showing me developmental versions of touchscreen avionics for a few years so I wasn’t surprised. The GTN 750/650 was the product of extremely intensive research and development by Garmin because, well, they were betting the farm on superseding the GNS 400/500 series, the most successful avionics units in history.

From the first time I heard about, or thought about, touchscreen avionics I had two big concerns. The first was how well could we pilots operate a touchscreen device in turbulence. And the other thought was how long would it take for us to break the decades old habit of having knobs and buttons dedicated to performing the same function all of the time.

My concern about using a touchscreen in turbulent conditions is, I think, unfounded. My fear was based on some push button avionics systems from the late 1970s that, when mounted in a vertical position on an instrument panel, were hard to operate in the bumps. But Garmin addressed most of those issues by designing in a kind of raised ridge around the screen that allows you to grip with several fingers while using one to touch in commands. As touchscreens are integrated into new airplane designs the screens will be tilted off the vertical so your hand can rest on the edge of the screen making operation even easier.

The issue of transitioning from dedicated knobs and buttons to touchscreen menus is actually being resolved by our everyday lives. Most of us are spending so much time using touchscreen devices that it has, or quickly will be, the norm. When I call Exec Air and ask them to fuel the airplane I use a touchscreen. I typically use my smart phone to enter the flight plan into flightplan.com. I use a touchscreen in the car when I drive to the airport. So it’s just natural that in the airplane touchscreens will be there.

The discussion of whether a touchscreen is easier or harder to use in the airplane is almost irrelevant. The real question is do touchscreens allow precise and desired control of our avionics? I think the answer is yes. And what flows from that is all sorts of benefits for the future.

Designing, certifying and manufacturing a touchscreen avionics system initially is probably about as complex, and costs about the same, as creating one with traditional buttons and knobs. But after that initial design, it’s game over for the touchscreen. Almost any changes in avionics operation, or new technology, or new regulation, can be handled via the touchscreen through new programming. If the design of the system, or its menus, or the steps required for normal operation are not optimum, they can be improved as we gain experience. Buttons and knobs lock us into the now—actually the past when the equipment was designed–but the touchscreen keeps the door open for almost continuous change and improvement.

As good as the touchscreen is for performing most avionics functions there are some tasks that just can’t be done better than with a twist knob or button. For example, can any control device beat a twist knob for setting the heading bug? No. Same for dialing in a baro setting, or a target altitude. Those types of simple and direct flying tasks we do dozens of times on every flight and have only a single level of complexity just can’t be improved on, and they won’t take on new forms and functions in the future.

Aviation must necessarily always be a step or two behind the newest technology because we only want to leave the ground using structural material and equipment with proven performance. But now, touchscreen technology is so embedded in all of our lives it’s time for it to move into our cockpits. Garmin has sold more than 90 million various electronic devices for all manner of uses and most of those use touchscreens. Pretty good testing to get ready to fly.

I was chatting with EAA founder Paul Poberezny last week. What an amazing guy. Through a very unusual set of circumstances during his military career during World War II and then as an officer in the Wisconsin National Guard he was able to fly an enormous variety of airplanes.
Most military pilots stay with fighters, or bombers or transports, and fly only a relatively few types in their category. But Paul flew everything from trainers to transports to fighters to tankers. He was showing me his military logbooks that often had him flying a single seat fighter and a large transport in the same day.
Paul’s career spanned the transition from pistons to jets and he regularly flew both at the same time after a pair of jet engines was added to the KC-97 tanker to give its four radial piston engines a boost. “Four churning and two burning is what we used to say about that one,” Paul said.
I planned to fly back home from Oshkosh to the Muskegon airport in Michigan on the other side the lake that afternoon. Paul asked me “do you just keep climbing until you get to 10,000 feet or higher so that you can make it across the lake?”
With two engines on my Baron I really don’t think much about engine failure over the water. The odds of losing both engines on one flight—if you have fuel onboard—is very remote. And holding altitude isn’t much of a question because over the water 100 feet will do it. The only obstacle is the big sand dune that hugs the eastern shore of Lake Michigan and is about 200 feet high near the Muskegon airport.
Paul was unimpressed by my logic. “What about an airframe failure?” he asked. “What if a propeller blade breaks off, or some system fails and you want to get on the ground right away?”
I had not really considered that possibility. I guess it’s the luxury of having been a pilot for only 40 years or so compared to Paul’s 75 years of experience. I haven’t flown through the really hairy days of aviation as he did.
It’s easy from the distance of years to glamorize the “golden age” of piston engine flying in large and powerful airplanes. Those piston engines pumping out thousands of horsepower were stressed to the limits—and maybe beyond the limits we would accept today. It’s hard to imagine the stress on a propeller being pounded by the pulse of 28 or more piston strokes generating 2,000, 3,000, or even a little more horsepower. Major failures had to be expected, and they did occur.
Lake Michigan itself also looms large for pilots in the middle of the country because unlike the four other Great Lakes, it must be considered on many trips. It’s pretty easy to skirt the southern shore of the other Great Lakes, but Lake Michigan is a 330 mile long north-to-south water hazard waiting to drown any pilot unlucky enough to end up splashing into its icy water. Paul grew up and learned to fly in Milwaukee, and spent most of his military career flying out of Wisconsin, so the big lake was always a consideration for him. I grew up and learned to fly on the south shore of Lake Erie which is much smaller, and unless you want to be in Canada, is not much of a factor on most flights.
I thought about Paul and his generation as I sat over Lake Michigan later that day. I had two and a half hours of fuel onboard for the 37 minute flight. My Continentals can only make 300 hp at sea level so the stress on the props, engine mounts and so on was coming from maybe 230 hp at cruise flight. And I was 1,000 pounds below maximum takeoff weight. Life for my airplane was easy. But Paul and his generation of aviators are reminders that flying wasn’t always so.