“I Was Sitting There with My Feet Up on the Desk … and Suddenly It Came To Me.…”
RICHARD WHITCOMB DISCUSSES HOW HE GOT TO BE ONE OF THE LEADING AVIATION INVENTORS OF THE LAST HALF-CENTURY
RICHARD WHITCOMB IS OFTEN ASKED WHAT MAKES HIM unique, how he has repeatedly managed to come up with conceptual breakthroughs that have cluded other talented aeronautics engineers. The answer, he believes, lies in his power of visualization. For some reason he can digest equations and wind tunnel data and turn them into a mental image, of air molecules flowing over airfoils for instance.
His earliest breakthrough was a very big one. In the years after the first supersonic flight, aircraft designers struggled to build a military jet capable of going faster than the speed of sound. The powerful drag forces that resulted from shock waves along a wing’s upper surface as it approached Mach 1 defeated them. Whitcomb realized there was a mathematical relationship between the drag forces and the cross section of the aircraft. He suggested that drag would be reduced dramatically if the fuselage were tapered at the point where the wings are widest. His “area rule” won him aviation’s highest honor, the Collier Trophy, in 1954.
He called his next big invention the “supercritical wing.” It utilizes a novel curved underside and a nearly flat top to produce more lift with less drag. His third major contribution was his design for “winglets,” small vertical airfoils placed at the tips of wings to counter drag-inducing turbulence. On May 3 of this year he was inducted into the National Inventors Hall of Fame.
Part of the Whitcomb story is his legendary nonconformity. At the age of 59 he abruptly resigned from his senior position at NASA and took on a project that seemed to violate laws of basic physics. As a deeply concerned environmentalist, Whitcomb spent 10 years searching for a loophole in the second law of thermodynamics. He didn’t find one, but he says he has no regrets about any career decision. He continues to encourage energy conservation, and he delights in describing the efficiency of the silver Honda Insight gas-electric hybrid vehicle parked outside his home in Hampton, Virginia.
How did you decide to go into aviation?
When I was a kid, I built model airplanes. Real flying model airplanes, not display models. Then I read an article in Fortune magazine about the Langley Memorial Research Laboratory (which is now NASA’s Langley Research Center), and I said, “That’s where I want to go.” I arrived there in 1943. In 1947 Chuck Yeager broke the sound barrier in the X-1, which we designed at Langley.
Although the X-1 was a big success, there wasn’t a lot of progress toward making supersonic flight routine until your area rule came along. How did that happen?
The X-1 was a rocket-powered vehicle. It was essentially an airplane, but rocket-powered. The rocket uses up fuel at a fantastically high rate, and so it would go up to supersonic speeds for only a few minutes. It wasn’t practical; we were just getting into the transonic age. We ran the transonic wind tunnel two shifts a day and sometimes seven days a week, so it was a very, very busy place.
You were a relatively young, inexperienced engineer when you came up with the area rule. How did you do it, when others who’d had more time in the business and more experience didn’t see it?
I’ve been asked this a hundred times. Why didn’t somebody think of it before? I realized that we knew nothing about what goes on near the speed of sound. So I made flow studies and wake surveys to see what happens at those speeds. Nobody ever has an idea out of the clear blue. You start off with experimental data. I had the idea, but I started off with data.
I’ve read that the actual moment of realization came suddenly.
Yes. Like in the comic pages, a light bulb above your head. It’s just like that. I was sitting there with my feet up on the desk, thinking about that data, and suddenly it came to me what it was.
I wouldn’t say it was counterintuitive, but it was very hard for other people to understand. They hadn’t seen my data. It took a while for the area rule to have an impact, but keep in mind that at this particular point, right in the middle of the deepest part of the Cold War, it was top-secret. Then, when people finally got the word about it, nobody wanted to be the first to use it. Let somebody else try it first! The Air Force was really behind us. What they did was award a contract to Convair to build a supersonic plane. But then, when Convair built it, it wouldn’t go faster than sound. So the Air Force told Convair that if they didn’t try the area rule, the contract would be canceled. That was one way to get them to use it.
And when Convair did use it, it went through the speed of sound very nicely. After the top-secret clearance was removed, in 1955, it became a very, very big story. It was on the top right of the front page of The New York Times . There was an article in Life magazine. I got my 15 minutes of fame.
How did the supercritical-wing project come about?
Since I was famous at that point, people would come to me and ask questions. Most of what they wanted was for me to sprinkle holy water on their ideas. A group came in that was working on a verticaltakeoff aircraft. They were going to turn the blast from the engine downward for takeoff. But I noticed that the air was having a controlling effect on the flow. The drag increase that occurs near the speed of sound was being delayed, and I sat down and asked why. I finally figured out that it was controlling the separation of the flow under the shock wave. I said, “Wait a minute. We can do that on an airfoil.”
So I had a model built, and sure enough, we had the first step toward the supercritical wing, or airfoil. Bill Lear was among the first to use it. He added a supercritical wing to his Learjet business jet. Cessna, with its Citation X, also adopted the supercritical wing. The big passenger transport people were slower to make the change. You have to invest so much money in a design change that it can make or break the whole company. However, the latest Boeing airplane has got a supercritical wing on it.
How about winglets? How did that invention happen?
The idea had intrigued me for years. I had read an article about the tip feathers on soaring birds. Vultures and eagles have those little “fingers” out at the tip. I said, “We ought to try that on an airplane.” After I got to that point, I thought, “Let’s put something in the tunnel.”
Way back, around the beginning of the twentieth century, an engineer proposed putting vertical surfaces at the tip to reduce the vortex strength. The scientists just put flat plates out there. Now, a barn door can fly if you put enough power in it. Those flat plates had been a very, very poor way of reducing vortex force, so I said, “Let’s design that thing at the tip with all the care and all the finesse that we used in designing wings.” I almost thought of calling them vortex diffusers, but that got a little too scientific.
Do you think we’ll ever see supersonic flight return to commercial aviation?
No. For a while there, after I became well known because of the area rule, the head of aeronautics at Langley said we were going to design a supersonic transport. There were three groups assigned to work on it, and each came up with a design. Then we handed them over to industry.
The industry people analyzed how they’d perform as real airplanes and came up with operating costs much higher than for subsonic airplanes. I said, “This is for the birds. This is for the elite. I want something that flies people, lots of people, so I’m dropping out of this whole thing.” One guy answered, “What’s the matter? You against progress?” I said, “That’s not progress,” and I washed my hands of the whole thing.
Recently NASA came up with a new design for a supersonic transport and again turned it over to industry to see what they could do with it. Conclusion: It’s still way too expensive. This new design was a lot better than the one we did more than 30 years ago, but it’s still just way too expensive. Some people think that if it’s technically possible, let’s do it. I say no way. You have to consider the costs.
When did you know that you were good at engineering?
As a kid did you think this was something you wanted to do as a job? Well, it just kind of came naturally. My father and both my grandfathers were engineers. We’d talk about engineering. My father would correct me when I used the wrong term about something, and he’d help when I needed something special.
Do you ever advise young people to go into engineering?
I shock people. I say, if you want to make an impact or have an effect, don’t go into aeronautics. It’s pretty well stabilized. No big things have come up in aeronautics since my inventions, and it has been 20 years since I left. Go into the life sciences. That is where very important things are going to happen. Now that we know something about DNA and so forth, ultimately we will be able to change ourselves. The church doesn’t think people should do this, because it’s trying to be God. I say, let’s try to be God. Let’s do something about ourselves. Maybe we can get rid of criminal tendencies and things like that.
Most people say we shouldn’t touch ourselves. But we’re not perfect by a long shot. That’s the next challenge.
What do you say to people who think technology is boring?
Many years ago C. P. Snow, who was both a novelist and a scientist, wrote about “the two cultures.” He said there was a scientific, engineering culture, and there was the humanities- the arts, writing, painting, that sort of thing. And the people who are into that part of culture are often absolutely uninterested in technology. Why? Because they don’t understand it. There will always be a whole group of people who are just not interested in technology. But I love it.
I experienced two cultures in high school. Most of high school was the other culture, like languages. I took Latin, French, and German and got C’s in all of them. If I hadn’t, I probably would have been an honor student. I did have chemistry and physics and all the math courses, but predominantly it was liberal arts, so I was not outstanding in high school.
Why did you spend so much time trying to reverse the law of entropy?
I wanted to work on the energy problem. I know most people think it’s impossible, but we still don’t know enough about quantum mechanics to have a real handle on it. I thought that if I really dug deep enough in quantum mechanics, there might be a clue to reversing this law.
I got in way over my head. I was an experimentalist trying to be a theoretician, and finally I just quit. It was driving me batty. Incidentally, it’s driven a lot of people batty.
I’m no longer trying to invent. There’s an old saying that if you don’t make a contribution by age 30, forget it. That’s absolutely true. Edison made most of his contributions by 30. When he got older, he came up with the damnedest ideas, like trying to get rubber out of goldenrod. That’s what I did trying to reverse the second law of thermodynamics.
Before that you made a rather sudden derision to retire. Why?
One thing was that I was losing control of my facility. A new division chief came in, and he wanted to put stuff in my tunnel. In all my years I had pretty much controlled the tunnel, and he wanted to put in something I didn’t like at all. I tried to convince the guy, the engineer involved, that it was impractical. I had never worked on anything that I considered impractical. Here was this thing that was going to be totally impractical, and it would have to use the tunnel for about three or four years straight. I said I just didn’t want to be a part of it.
The other thing was, and I hate to say this, that I couldn’t think of anything else to work on in aviation. Nobody else has either. No one has come up with anything truly new in years. It’s just a matter of details now, not new approaches. That is why I quit.