The Dream Machine

by Richard Whittle

  Unlike Kelley, the Philadelphia-born Lichten was rough around the edges, Spivey found, and “if he didn’t like something you did, he’d upbraid you pretty good.” Nearly every Bell engineer who worked with Lichten seemed to have a story about a run-in or confrontation with him. Towering and handsome, Lichten was also domineering. He was never crude, but he was often dismissive of subordinates. If he didn’t agree with what you were telling him, he might just turn on his heels and walk away without a word. If he really didn’t like what you were telling him, he might belittle you on the spot. Lichten had earned his degree in aeronautical engineering from the Massachusetts Institute of Technology in 1943. He set great store by analysis and calculation, which wasn’t the habit at Bell. Starting with Art Young and Bart Kelley, the culture among engineers there had been trial and error, or “cut and try.” That also bothered Kenneth G. Wernicke, Lichten’s deputy in those days. Wernicke liked Lichten. He thought he was “hard on people because he expected more of them than they were capable of. ” Lichten looked down on those who disappointed him, and a lot of people didn’t like him.

  Even so, Lichten oversaw the engineering of some of Bell’s most successful helicopters over the years, including the Huey for the Army and Marines and the civilian JetRanger, a big seller. Outside work, he was a political liberal whose passion was civil rights, an understandable interest, perhaps, for a Jew who came to maturity during World War II. Lichten was a life member of the NAACP. He was a leader in the Dallas chapter of the American Jewish Committee, the Dallas United Nations Association, the Dallas chapter of the American Civil Liberties Union, and the Texas Civil Liberties Union. Like Kelley, he also belonged to the Dallas Chamber Music Society. Lichten’s obsession, though, what drove him most throughout his career, was his dream machine: the tiltrotor.

  Lichten spoke of the tiltrotor as an addiction. When he made Wernicke his chief tiltrotor engineer in 1965, Lichten warned his protégé not to make the concept the “only thing in your life,” as Lichten said he had done. “I don’t want you doing that,” Lichten told Wernicke. “I want you to realize there are other things besides that in life.’”

  The tiltrotor was Lichten’s “baby,” as Wernicke saw it, but in truth, Lichten was only the concept’s adoptive father. The configuration’s technological DNA can be traced to Germany and the Fw 61, the helicopter with side-by-side rotors that so impressed rotary wing guru Alexander Klemin and other Americans in the 1930s. Among those who saw Hanna Reitsch fly the Fw 61 in Berlin’s Deutschlandhalle in 1938 was Larry Bell, one of the industrialists President Roosevelt sent to Germany that year to assess Nazi war-making capacity. Another who saw the Fw 61 in Berlin was W. Laurence LePage, a British-born engineer who had worked on Autogiros for Harold Pitcairn and for one of his licensees. LePage came back from Germany with a film of Reitsch flying the Fw 61. He showed it to the Army and to the 1938 Rotating Wing Aircraft Meeting in Philadelphia, which he helped organize. Shortly afterward, LePage and Haviland H. Platt set up a company in Eddystone, Pennsylvania, to build a similar helicopter. Among the engineers they hired was Bob Lichten.

  Like the German machine, the Platt-LePage helicopter had two rotors placed laterally, where an airplane’s wings would be, held away from the fuselage by winglike outriggers. The company also designed a similar machine with mechanisms to allow the rotors to tilt forward. Platt-LePage never built this tiltrotor, but Lichten fell in love with the concept. It was a fairly elegant solution to a central problem for convertiplane designers: how to equip an aircraft with two forms of lift and thrust—one each for vertical and horizontal flight—yet avoid loading it down with two sets of machinery that would add impossible amounts of weight and aerodynamic drag. After World War II, as the development of the helicopter kindled new interest in the convertiplane, Lichten and a couple of partners formed a new firm to develop a tiltrotor. Fittingly, given what the tiltrotor was meant to do, they called their firm the “Transcendental Aircraft Company.”

  Within two years, Lichten left for Bell, where helicopter inventor Art Young had been intrigued by the convertiplane idea for some time. At the First Convertible Aircraft Congress in Philadelphia in 1949, the year after he joined Bell, Lichten showed a film made in the early 1940s of Young flying a crude model convertiplane with a single tilting rotor on a wing. Young had established a project at Bell to pursue the technology, calling it the Model 50 Convert-O-Plane. In 1947, though, with Bell now producing helicopters based on his earlier work, Young left the company and returned to his farm in Pennsylvania. Young was more interested in philosophy.

  When Lichten brought his ideas about the tiltrotor to Bell the next year, he was only one of many aircraft industry engineers embarking on such a project. By 1949, when the First Convertible Aircraft Congress proclaimed self-described eccentric Gerard Herrick the “Father of the Convertiplane,” the center of gravity in the quest for the dream machine was rapidly shifting. It was passing from the realm of maverick inventors to a hungry aircraft industry and a military gearing up for new conflicts. That year, the communists took power in China by winning a civil war. The Soviet Union tested its first atomic bombs. The United States and its European allies formed NATO, the North Atlantic Treaty Organization, to protect Western Europe against a feared Soviet invasion. With an alarmed Congress providing money, the U.S. military soon would start rearming for the coming confrontation with communism.

  At the moment, though, American aircraft companies were still struggling to recover from the loss of their huge World War II contracts, and they were looking for new products. Bell Aircraft’s revenues had plummeted from $317 million in 1944 to $11.5 million in 1946, the year after the war ended. Larry Bell and others in the new helicopter industry were working hard in the late 1940s to gain public acceptance for their odd-looking new aircraft, but the “egg-beaters,” as wags dubbed them, were catching on slowly. Even the military was hesitant about them. The Army Air Forces and the Coast Guard had used some during World War II, but those services still regarded the machine as a work in progress. Helicopters were still too fragile and new for the military to adopt wholesale. Even forward-looking tacticians and strategists were largely unsure what the helicopter could really do and how best to use it. Their frame of mind was illustrated by a cartoon in the July 1948 issue of the two-and-a-half-year-old magazine American Helicopter. The drawing shows an Army officer slouched in a folding lawn chair, his uniform cap on the ground, his jacket draped on the side of a small, round garden table that holds a cocktail glass. Overhead, held in place by a rope tied to a stake in the ground near the lounging officer, hovers a small helicopter bearing the military’s star-in-a-circle insignia. The officer cools himself under the rotor downwash as two soldiers in the lower right-hand corner take in the spectacle. “I was wondering what that infantry colonel was going to do with a helicopter,” one says to the other.

  When that cartoon appeared, the only service fully sold on the helicopter as a weapon of war was the Marine Corps. The Marines were studying helicopters as a better way than landing craft to get troops from ship to shore in amphibious operations. During the Korean War, 1950–53, the helicopter would come into its own, proving a great way to evacuate wounded, carry supplies to troops, rescue pilots downed behind enemy lines or at sea, and on occasion take soldiers and Marines into battle. In 1948, though, the only thing most military officers knew for sure about helicopters was that the things were frustratingly slow. And this was the dawn of the jet age. The turbojet and the turboprop, engines developed during World War II, were enabling aircraft designers to come up with machines of phenomenal speed. The power of such engines was also leading more and more engineers and military officers to take the old convertiplane dream seriously for the first time. With the sound barrier broken and people talking about space travel, anything seemed possible.

  Against that backdrop, the U.S. military—like the militaries of the antagonistic Soviet Union and of America’s richest allies, Britain, France, and West Germany�
�spent millions of dollars over the next two decades on experimental convertiplanes. John P. Campbell, a senior NASA aeronautical engineer, wrote a book on the subject in 1962. He concluded that, counting the helicopter, there were sixteen categories of what experts by then were no longer calling convertiplanes but instead “VTOLs,” an acronym for Vertical Take Off and Landing, pronounced “VEE-talls.” A VTOL aircraft’s type depended on what method of propulsion was paired with what means of converting from vertical to horizontal flight. There were four basic methods of propulsion: rotors, propellers, turbojets, and ducted fans, the last meaning propellers or multibladed fans spinning inside enclosed cowlings. There were four basic methods of conversion: tilting the whole aircraft from vertical to horizontal, tilting only the thrust, deflecting the thrust downward for vertical and rearward for horizontal flight, or using two separate methods of thrust on the same aircraft—one vertical, one horizontal. By the time Campbell published his book, almost all sixteen forms had been tried, mostly with poor results.

  Some of the designs the military and NASA paid for look downright zany in retrospect. As has always been the custom with aircraft, they were known by an alphabet soup of letters and numbers. The Navy financed the Convair XFY-1 and Lockheed XFV-1 “tail-sitters,” also known as “Pogos.” Both resembled conventional airplanes, except that they had two huge, counterrotating propellers on their noses and were designed to take off literally sitting on their tails and pointing straight up. This was hard on the pilot, who was expected to begin his flight lying on his back with his feet in the air and end it the same way, landing the monster on its tail while looking over his shoulder as if parallel parking. The Convair XFY-1 took off and landed this way several times and even converted from vertical to horizontal flight. The Lockheed Pogo flew as a conventional plane but never managed to take off or land vertically. The Navy abandoned both designs in the mid-1950s as impractical, especially with the introduction of jet fighter planes.

  Equally bizarre-looking were a couple of “deflected slipstream” aircraft financed by the Army, the Ryan VZ-3 and the Fairchild VZ-5. They were essentially conventional airplanes with propellers on their wings and massive flaps that directed the propeller thrust downward so they could take off and land vertically or hover—at least in theory. Neither showed great promise, and one test pilot barely managed to eject before the VZ-3 went out of control and crashed as he tried to convert it. The U.S. and other militaries financed, and aircraft companies produced, dozens of other VTOL prototypes. Thousands more were designed but never built. In the 1990s, aerospace engineer and VTOL historian Michael J. Hirschberg refined a graphic of the various attempts that someone at the old McDonnell aircraft company had put together in the 1960s. The graphic, which can be found on the Internet, took the form of a “Wheel of Misfortune.” The wheel represented only those VTOLs actually built. There were forty-five, not including three dozen exotic helicopters Hirschberg later wished he’d included.

  When Hirschberg published his version of the wheel, only one of the VTOLs on it was still flying, and only two had ever gone into full production and service. One was the Soviet Yak-38 “Forger,” withdrawn from service in 1992. The other was the Harrier, a “jump jet” designed in Britain in the 1960s for the Royal Air Force and bought by the U.S. Marine Corps in the 1970s and 1980s. This “vectored thrust” aircraft, which could point its jet exhaust downward to take off and land vertically or hover, was strictly a one-seat fighter plane. It was far removed from the passenger machines the true believers in the convertiplane had envisioned, and by the mid-1970s, engineers had concluded that building a VTOL passenger jet was impractical. For one thing, jet engines create thrust by accelerating a relatively small stream of air to high speeds, which requires burning fuel at high rates. A machine big enough to carry passengers would burn so much fuel lifting off vertically it would have little range. The convertiplane believers were after an aircraft without such limitations, one that would carry passengers and “do in the air substantially everything that a bird can do,” in the words of 1930s aeronautics icon Alexander Klemin. They wanted to revolutionize not only military but also civilian aviation. They wanted a dream machine.

  * * *

  There was a reason the quest for the convertiplane was like searching for the Northwest Passage or seeking the Holy Grail. The engineering problems were devilish. One of the biggest hurdles was weight.

  Aircraft designers judge helicopters and airplanes partly on their “empty weight” to “gross weight” ratio, meaning how much they weigh sitting on the tarmac unloaded and with no fuel in their tanks versus how much they weigh carrying their maximum load. An ideal but frequently elusive target is an empty weight to gross weight ratio of 50 percent. This makes it possible to carry some combination of passengers, cargo, and fuel equal to the weight of the machine itself. As Bell engineer Ken Wernicke saw it, that ratio was the problem that stumped most VTOL aircraft designers. “A lot of these things have been able to lift themselves off the ground but they were so heavy they couldn’t carry very much fuel and they couldn’t even carry any more payload,” Wernicke explained. “That is the biggest issue: it’s the weight, because in any case, you’re either going to have to have a double lift system or you’re going to have to have a double propulsion system to move you forward.” Like his mentor Bob Lichten, Wernicke saw the tiltrotor as the best solution, though he tried others. Once he and a brilliant Italian engineer Bell had hired, Emilio Bianchi, spent months trying to design a worthwhile “compound helicopter,” meaning a conventional helicopter with an added means of propulsion for forward flight, such as a propeller or jet. The extra form of propulsion yields a helicopter that can escape the speed limit retreating blade stall and other aerodynamic limitations usually impose on rotors, but the added weight means the aircraft can carry less fuel, which limits its range. One day Bianchi threw his pencil down on their drawing board in disgust and sputtered, “This is all monkey vomit!” Wernicke and Bianchi concluded that a compound helicopter just wouldn’t work well enough to justify itself because its weight would limit its range to the point where its additional speed became irrelevant. “If you can’t go very far, why go very fast?” Wernicke reasoned. “It doesn’t take you long to get there anyway, because you’re not going very far.” Moreover, such a machine isn’t aerodynamically efficient in forward flight “because now the crap you use to hover with, you’ve got to drag it along with you.”

  That was the advantage of a tiltrotor, the way Wernicke and others at Bell saw it. If you tilted the rotor over and used it as a propeller—presto, no extra “crap” creating drag, and no more weight penalty. Wernicke loved that.

  With Bob Lichten in charge of the project, Bell Helicopter won a contract to build an experimental tiltrotor as part of a 1951 converti-plane competition run by the Air Force but financed by the Army and the National Advisory Committee on Aeronautics, NASA’s predecessor. Two other contracts went to McDonnell and to Sikorsky Aircraft Company, which by then was shaping up as Bell’s chief rival in the helicopter market. McDonnell offered what amounted to a compound helicopter. Sikorsky designed but never built a jet with delta-shaped wings and a rotor atop its fuselage that was to fold away after lifting the craft into the air and unfold to set the aircraft down.

  The military designated Bell’s tiltrotor entry the XV-3 Convertiplane.

  * * *

  A single glimpse can give birth to infatuation. Infatuation can mature into passion, and passion is obsession’s parent. Dick Spivey caught his first glimpse of the XV-3 the day he arrived at Bell in 1959. It was sitting on the flight line as Warren Jones showed him around. Spivey was infatuated right away.

  This first Bell tiltrotor piqued Spivey’s curiosity because it was such a “strange-looking beast, compared to everything else,” he remembered years later. The XV-3 had been cobbled together with parts from existing aircraft, and it showed. It looked like a helicopter that had been rear-ended by an airplane. From the wing forward, the fuse
lage was boxy, like most helicopters in those days, with windows enclosing the cockpit and extending behind it. From the wing back, it was all airplane. Except that protruding from its wingtips were two small, teardrop-shaped swiveling pods called “pylons,” each of which held a two-bladed rotor measuring twenty-three feet in diameter. The engine that drove the rotors was inside the fuselage, which was painted silver. The pylons were bright orange, as was the rudder. The craft’s oversized tail was silver, too, except for a yellow triangle at its bottom that bore the label “NASA” in big black letters. (NASA had taken the place of the NACA the previous October.) The top of the tail was labeled “U.S. Army,” also in black letters. A pair of skids served as landing gear. Spivey thought it was really cool.

  The XV-3 Spivey saw was the surviving one of two Bell had built. The first had been destroyed two and a half years earlier during one of its first flight tests, leaving its pilot, Dick Stansbury, crippled for life. During initial flight tests in August 1955, when another pilot took the XV-3 up into a hover, the craft started shaking. Bell and NASA put it through wind tunnel tests for a few months to study the problem, then Stansbury climbed in on October 25, 1956, to test it again in a hover and see what it would do when the rotors were tilted forward. He got the XV-3 to hover, but when Stansbury moved the rotors forward 17 degrees, the craft started to shudder violently, shaking the cockpit so hard he blacked out from being slung around inside. The XV-3 went out of control and fell to the ground, breaking Stansbury’s back. Afterward, Bell and NASA spent a couple of years figuring out the cause: a phenomenon called “dynamic instability,” sometimes referred to as “air resonance,” in which centrifugal force can start a propeller or a rotor and its mast wobbling at ever-increasing rates if the structure holding them isn’t built just right. The first XV-3 had three-bladed rotors with hinges in them so they could flap up and down and lag independently, a standard feature on helicopter rotors of the sort. The hinges were meant to keep the rotor blades from bending their mast as the wind buffeted them up and down. Complex aerodynamic forces, however, caused the side-by-side rotors to get so far out of kilter with each other they were shaking the aircraft to the point it was uncontrollable. Bell and NASA engineers finally solved the problem, in part by substituting a two-bladed rotor, in part by putting a strut under each wing. Without computers to analyze such things, it was daunting, time-consuming work. After a long recovery, Dick Stansbury came back to Bell as a research and development engineer, hobbling around on aluminum braces that went up over his elbows, but still enthusiastic about the tiltrotor.