Learning To Fly Again For The First Time
Building a painstakingly accurate reproduction of a 100-year-old airplane is one thing -- figuring out how to fly it, and not get killed in the process, is quite another. That's the challenge faced by The Wright Experience team as they prepare for the once-in-a-lifetime celebration of flight on December 17 at Kill Devil Hills.
Scott Crossfield was the first pilot ever to fly past Mach 2. He flight-tested the X-15, and he helped train the very first astronauts. Now he's soaring aboard a reproduction of a 1902 Wright glider, built of sticks and strings. He flies in 1,000-foot hops, towed on a 200-foot rope behind a truck on a grass strip in Warrenton, Va., and tries not to get busted up in the process.
"We're learning to fly the same way the Wrights did," Crossfield says. "We're working in very precise, small steps, learning as we go, to find the limits and determine the flight envelope." So the glider practice is the first step. Over 140 tow-flights, each less than 60 seconds long, split among the four pilots on The Wright Experience team. That was enough for each of them to get it nailed straight down the runway, and handle some gentle banks and turns. As they learned, they gradually tweaked the design, changing it to handle more and more like the 1903 Flyer -- the one they will fly at Kitty Hawk for the Centennial celebration next month. They replaced the glider's single canard with a double one, and gradually added lead weights along the struts to destabilize it.
Yes, making the glider less stable is the trick to making it more like the '03 Flyer, an airplane well-known for its squirrelly handling. "It's just about the most miserable airplane to fly you could imagine," says Crossfield. "Every airplane that's been built in the last 100 years is a better airplane than that."
Ken Hyde, founder of The Wright Experience, knows the Flyer will be tough to handle, and he's grateful to have Crossfield's help. "Scott adds so much to the equation, with his background in flight testing and engineering," Hyde says. "When he flew the X-15, those pilots didn't just go jump into the cockpit, you know. They spent a lot of late nights working on airplanes, very hands-on. Same thing here. Scott's here in the hangar, down on the floor under the wing, figuring things out."
|The Wright Experince Pilot Team: Ken, Kevin, Terri, and Chris.|
It's that same hands-on willingness that Hyde looked for in choosing his pilot team. He acknowledges that it might have been easier to train people who had never flown before, instead of the experienced pilots he's working with now. "So much of it has been having to unlearn the instincts they've acquired in their prior training," he says. "Pilots today don't know how to fly an unstable aircraft -- something that slides sideways in the air." But each member of his flight team -- himself, Kevin Kochersberger, Terri Queijo, and Chris Johnson -- pitched in and got to know the airplanes from the bottom up, inside out, back to front. Just like the Wright brothers -- and Crossfield -- did. Hyde decided these were the right people to be out there flying.
This month, the team is in North Carolina, at a secret location somewhere in the Outer Banks -- "Though I suspect, once we cross over that bridge, it will be tough to keep it much of a secret," says Hyde. First, they'll train on the glider in free flight, without a towline, launching it down the side of a sand dune. Then they will flight-test the '03 Flyer for the first time, firing up the engine and guiding it along a rail, until its fragile wings bite enough air to lift off. All four pilots will continue to train, though last summer Kochersberger and Queijo were chosen as the final two who will fly on the 17th. "The backups need to be equally prepared," says Hyde. "Just like in any test program at NASA or anywhere." Who goes first on the 17th will be decided by a coin toss -- just as it was in 1903.
Concessions to Modern Engineering
It's a long drive to the Outer Banks from Warrenton, but Hyde's devotion to detail doesn't go to the extreme of replicating the Wrights' tortuous trip via train and boat -- he's traveling on paved roads in comfortable trucks. Likewise, he has taken advantage of modern technology to help train his pilots. NASA's full-scale wind tunnel at Langley Research Center was pressed into service, testing the Flyer and other Wright aircraft -- powered and unpowered -- piling up scads of data about lift, drag, pitching moments, and more.
|The Wright Model B simulator.|
Much of that data was loaded into a flight simulator program built by Bihrle Applied Research (BAR). Engineers at BAR worked for two years to create computerized simulations of the '02 Glider, the Flyer and the 1911 Model B. At the Wright Experience workshop, the simulators' controls are just like those in the airplanes. In the two earlier aircraft, the pilot lies prone atop the lower wing, with a hip cradle to warp the wings and a stick to control the canard. There is no separate control for the rudder; its movement is interlaced with the twisting of the wings. (For an interactive illustration, see NOVA's Web site.) The pilots can practice by lying prone in front of a computer screen. In the Model B, the pilot sits upright.
"The simulator was helpful in getting us familiar with what to expect, and in predicting the effect of various atmospheric conditions," says Kochersberger. A professor of mechanical engineering at the Rochester Institute of Technology, he led the testing of the gliders in the wind tunnel. "But the flights are the real benefit to the training program." All the number crunching and sophisticated computer graphics in the world, it seems, still cannot quite replace reality. "Once the airplane takes off," Kochersberger says, "all bets are off."
The '03 Flyer was built for just one purpose: to prove the Wrights' theories of flight. Ease for the pilots -- and longevity of the airframe -- were not part of the equation. "It's very delicate and fragile," Kochersberger says. "It's upset by any gust. It's noisy, and it vibrates. Flying it requires concentration and anticipation. The training has paid off quite a bit. We're getting pretty comfortable."
Hindsight Isn't Even Enough
|The Wright Experince Workshop.|
Hyde's advantages over the Wrights are not purely technological. He has the historical perspective of knowing exactly what the brothers accomplished, how they did it, and how it all turned out. But that's still not quite enough. "I wish I had two-and-a-half or three hours of dual with Wilbur Wright," he sighs. "These are not toys. They are real airplanes. And with authentic aircraft come authentic risks."
Hyde learned about those risks firsthand earlier this year when he crashed his Wright Model B into a treetop. He was conducting a taxi test on the airplane. "All of our data showed that it would take more than 200 feet to get into the air," Hyde says. "So it was a surprise when it lifted off at about 125 feet." Once airborne, Hyde flew it as best he could for about 10 minutes, but when it began to skid and headed for a tree he knew he couldn't stop it. He broke his wrist, but it's mended now, and the airplane is being repaired. But the incident was a reminder of the limits of computer-generated test data, and the dangers to flesh-and-blood test pilots.
The Wrights were methodical in their own test program, and fiddled endlessly with every bit and piece of each aircraft, trying to solve the elusive puzzles of control, power, and lift. Hyde and his team have exhaustively researched all the archives they can find, built their own library, and amassed 33 linear feet of original documents, but still there are gaps. So they try to recreate the Wrights' dogged methodology: Testing and re-testing every component, and asking and re-asking every question about every eventuality they can think of. "The Wrights wrote home to their father from Kitty Hawk that they were being very careful, testing that all the wires and components were strong," Hyde says. He is doing the same, gradually building confidence in his total airplane by testing each and every bit and piece.
It's been 10 years of reverse engineering, and along the way Hyde's respect for the Wright brothers -- their meticulous methods, their analytical minds, their perseverance and bravery -- has only deepened. "This was a very well thought-out test program," he says. "The Wrights tore up a lot of airplanes, but they weren't reckless. They wanted to live to fly another day."
Engine and Propeller, Too
|Wright 1901 propeller tests in the Langley Full-Scale Tunnel|
While the Wrights are often credited with solving the mystery of control, their other technical advancements may have been just as important in getting the airplane off the ground. "The '03 propeller design was the hardest thing they did," says Hyde. "They fussed and argued over it. The Wrights got the least credit for that, but it might have been their most significant achievement. Nobody else had figured it out."
The Wrights had realized that the propeller acted like a wing moving on a helical path, like a screw. They tested airfoil models in their wind tunnel, patiently searching for the most efficient design. "They were looking for the least resistance and the best lift," says Hyde. Thanks to all of their figuring and fidgeting during the tests and trials, they were able to build a very efficient prop, carved with care from laminated wood.
They followed the same dogged path to create an innovative engine, with an aluminum casing. "It was very progressive for the time," says Hyde. The engine produced about one horsepower per 12 pounds of weight. In contrast, the engine in Langley's machine, which was trying to fly during the same era, weighed in at 62 pounds per unit of horsepower, Hyde says.
Working with that total package -- a lightweight engine, an efficient prop, and their somewhat dicey but workable control system -- the brothers were able to get the Flyer to lift off and fly on a windy day on the dunes, 100 years ago. That was just the beginning of their work, of course. That was just the prototype.
Test Flight on The Big Day
|If you were flying the 1903 Flyer, this would be your instrument panel.|
Despite all the effort, the training, the research and the preparation, what will happen on December 17 remains unpredictable. "We're still not sure we can do it," Hyde said last month. "We're developing an envelope for what weather we can fly in, so far as temperature and winds. Both factors are very important." Does he need a 27 mph wind to take off, like the Wrights had in 1903? "I think if it's blowing 27 miles per hour, we're going to tie that thing down good and tight," he says. "That's a pretty stiff wind, it would certainly be 'a wild ride,' as the Wrights put it. But we're hopeful that the sky gods will be kind and we'll be able to fly on December 17. If not, we'll have flown it by then and we'll have it on videotape, but we know that's not what the people want."
Just before departing for North Carolina, Crossfield said he had determined what the flight envelope is, but he's keeping it to himself. "I know what's best for the safety and success of the program," he says, and he wants to be able to adjust those limits without having to explain or justify his decisions. And what did he base that on, those decisions about the envelope? "On my 70 years of experience in aviation."
But despite all those decades, there are limits to Crossfield's expertise: "I can't tell you what happens next," he said, not because he won't, but because he has no idea. "It's been a mystery all the way."
The Wright Experience is working under commission to EAA's Countdown to Kitty Hawk project to build the 1903 Flyer, the only reproduction scheduled by the National Park Service to fly at Wright National Memorial on December 17.