What Is a Revolutionary Airplane?

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Oshkosh is the place to see and hear about new airplanes, many of which propose to revolutionize a category, or even create a new category of aircraft. The fact that virtually none succeed doesn't seem to dampen the enthusiasm of pilots, developers or investors. I have often said, and firmly believe, that to stay alive in an airplane you should expect the very worst at any moment and be prepared to deal with it. Optimistic pilots don't tend to last long. Believing that you or your airplane can handle bad weather, clear the trees at the end of the runway when the airplane manual suggests it will be close, or make those last few miles even though the fuel gauges show empty is a direct path into an NTSB report. I suspect the final thoughts of many pilots were "I thought this would work."

But that tried and true attitude toward safe and conservative flying is suspended by many pilots when they encounter a new design that promises never before seen performance at a price that has also never been achieved. Instead of thinking of all of the things that can go wrong with a new design -- as you should think of all of the potential issues before you push the throttles forward -- pilots want to believe that some new aerodynamic or construction technique, or new materials, have laid waste to all successful airplanes that have come before and that the new magic airplane will be in production in mere months.

I have come to understand why startup airplane companies must make the most outlandish claims, even though their odds of success are astronomical. If a startup were to propose an airplane that can actually be certified and built at a price that can sustain a business, they would have no market because it is exactly those kind of airplanes that the existing and established manufacturers are building.

Critics of the industry say it is, in fact, this very conservative attitude by the successful manufacturers that holds back progress in aviation. They correctly point out that the establishment won't take unreasonable chances with an airplane design or pricing so it is left to startup companies to keep dreams alive. On the other side curmudgeons like me point out that the establishment became what it is by staying with what is possible and reasonably predictable.

But over the decades there have been revolutionary airplanes, ones that created their own category and have grown and prospered. And most of these designs came from the establishment.

High on my list of revolutionary airplanes is the Cessna Caravan. Nothing is more prosaic than the components of a Caravan, but it is the design choices that Cessna made that created the revolution. The Pratt PT6 turboprop had been around for years when the Caravan concept was developed nearly 30 years ago, so that wasn't new. A strut-braced high-wing metal airframe is the most built configuration ever, so no revolution there. A handful of big singles, such as the de Havilland Otter, had been built in the past but they were piston-powered taildraggers. What Cessna recognized was the need for a large capacity single-engine turboprop that could economically carry freight, passengers or a combination with the reliability and cost not available in any other airplane.

FedEx gave the Caravan a solid start, but its unique combination of qualities has spread the mission of the airplane far, far beyond overnight package hauling. In fact, the Caravan is flying missions that simply were not performed by airplanes before it existed. To me that is the pure definition of a revolutionary airplane -- one that creates its own mission as pilots find ever more ways to use its capability.

Revolutionary Gulfstream in flight test 50 years ago.

Another revolutionary airplane first flew 50 years ago, the Grumman Gulfstream. There may be arguments over what was the first true business jet, but there is no debate over which turbine-powered airplane was built first with the express mission of carrying passengers on business trips. It was the Rolls-Royce Dart-powered Gulfstream. We now call it the Gulfstream I, but in the late 1950s there was no need for the Roman numeral because there was only one Gulfstream.

Again, Grumman engineers and visionaries didn't need a revolution in engines, aerodynamics or materials. They were all at hand. The revolution was the idea -- and risk -- that companies would pay what it really costs to fly their people in an airplane that had a cabin with standup headroom, the structure and system reliability of a true transport airplane, reasonable cruise speed, and enough range to cross the country, at least when flying downwind. The cost was frightful and most in the industry, and no doubt many within Grumman, doubted companies would buy the Gulfstream. But the G-I created the large cabin long-range business airplane category that Gulfstream still leads today.

The company did the same thing again with the G-II, the first transcontinental business jet, and again with the G-III that could cross the Atlantic every time westbound, the G-IV that linked any two continents, and the G-V that can leap from New York to Tokyo. And now the G650, using proven technology honed to a finer edge than ever before, promises Mach .90 cruise between most any two city pairs in the world.

I have to put the TBM 700 on my list of revolutionary airplanes because it, too, pioneered a new and successful category. The airplane was the brainchild of the people at Mooney and Socata who understood that many pilots were comfortable with only a single turbine engine and would pay what it costs to go fast and far in such an airplane. The TBM design is very conservative, and so are its materials and systems. No magic was needed to create it, just good, solid aerodynamic design and a belief that there is a market for such an airplane at the price necessary to cover the cost of manufacturing and support. The Pilatus PC-12 with its much larger cabin, and the Piper Meridian with its lower cost and more modest performance, prove every day that the people who imagined the TBM were right about single-engine turboprops.

Even the Falcon 7X with its fly-by-wire controls, a first in a business jet, is revolutionary without resorting to unproven technology. Dassault has more than 20 years of fly-by-wire experience in its military fighters, so it was transferring what it already knew how to do to a new category. All large business jets now in development will use fly-by-wire controls, but the 7X was first.

So what is the next revolutionary airplane? One of the several single-engine jets in development? Perhaps. I think the acceptance of the single-engine turboprop proves that many pilots are more than comfortable with one engine, and the fuel efficiency is obvious, so a market is there. But the jet single that succeeds will be, I think, the one that uses the most proven aerodynamic design and most conservative performance and cost predictions. Creating a new category of airplane is not the time to take chances on unproven elements of airplane design, but rather the time to put those known quantities together in a different way.