“Anything that anybody had ever wanted, they asked for,” Wernicke told me. “It was going to be excessively heavy. They wanted too much and it could only be big enough to go down a carrier elevator. The whole thing was bad news.”
Ken Wernicke’s view was hardly insignificant. He was Bell Helicopter’s premier tiltrotor engineer. Arguably, that made him the premier tiltrotor engineer in the world. No one but Bell had ever built a tiltrotor that worked.
Slender and serious, with short brown hair and handsome features, Wernicke had been tiltrotor pioneer Robert Lichten’s protégé. Wernicke joined Bell in 1955, after earning a master’s degree in aeronautical engineering from the University of Kansas. Aeronautical engineers, like artists, tend to understand and work in several aspects of their field but specialize in just one. Art has its great painters, architects, and sculptors, but only a rare genius such as Michelangelo masters multiple disciplines. Some aeronautical engineers are aerodynamicists, who predict air flows and their effects on aircraft. Others are dynamicists, who detect and find ways to reduce or eliminate stresses caused by the motion of an aircraft and its moving parts. Structural engineers focus on configuring aircraft to withstand the aerodynamic and dynamic forces they encounter in flight. Wernicke was a Michelangelo, brilliant in all disciplines. “He was good in everything. It didn’t matter: aerodynamics, dynamics, structures,” said Troy Gaffey, who worked for Wernicke as a dynamicist on the XV-15.
In the 1960s, Wernicke headed a team of eight or nine tiltrotor engineers who included his twin brother, Rodney. Back then, for a company that was churning out thousands of combat helicopters for the Army and Marines to fly in Vietnam, the tiltrotor was a sideshow, an indulgence, a long-shot bet on the future at best. Wernicke’s team was largely left alone. They worked at desks and on drawing boards in a cramped little space on the second floor of Bell’s engineering building, one of two yellow brick structures fronting on Highway 10 in the sparsely populated Fort Worth suburb of Hurst. Their little bullpen was separated from a larger herd of research and development engineers by a low wall topped with frosted glass framed in metal, but it was noisy in there. A secretary who sat near Wernicke was always clacking away on her electric typewriter. The engineers were constantly talking, either to each other, to someone on the phone, or to a colleague from another section of Bell’s engineering department who’d dropped by to noodle through some problem.
“We’d have big arguments about various things,” Gaffey recalled. “It was exciting. We were finding things out. It was the Age of Discovery. Unless we were dead asleep, we were thinking about the tiltrotor and how we were going to solve the problem. We had a great passion to get the tiltrotor up and running.” Often, one of the tiltrotor engineers would get up and take an idea down the hall, sit on the edge of a colleague’s desk, show him a sketch, and say, “What do you think of this?” or “Look at this!” As the engineers talked, they’d take turns drawing their ideas. Engineers find it easier to talk about their work with pen or pencil in hand and a piece of paper in front of them, even if it’s just a napkin. They’ll sketch a rotor blade or a tail fin, draw a graph or diagram, write out an equation to show what they mean. This is true even today, though computerized design software long ago replaced the drafting board and slide rule in the engineering workplace. In the 1960s, engineers still worked on paper.
They also played with it. Gaffey loved to tell how, one day around 5 P.M., the tiltrotor engineers held an impromptu contest. They made paper airplanes out of their time cards, engineered them for distance by attaching paper clips, then took turns standing on top of the office conference table and flinging the planes to see whose flew farthest. Wernicke had just climbed up on the table to launch his entry when Bell’s dignified president, Jim Atkins, happened down the hall past the open door. “I can still remember Atkins looking at him like, ‘What are you doing?’ ” Gaffey chuckled.
Atkins’s office was in the administration building, another yellow brick rectangle facing Highway 10 and situated on the other side of a guard shack just inside the front gate. Bell’s executives, lawyers, marketers and other nonengineers were in that building. Gaffey called it “the Far Side,” after the zany comic strip by Gary Larson. Bell’s engineers were often at odds with its management and marketers, though until Bell got its contract to build the XV-15 for NASA in 1972, the tiltrotor engineers were an exception. They were just a small band of brothers on a quest for aviation’s Holy Grail, largely undistracted by considerations other than science. As Bell designed the XV-15, though, the number of tiltrotor engineers grew. They moved into a larger workspace and, in effect, into the real world. When Atkins decided the tiltrotor was ripe for harvest and Bell turned the XV-15 into a marketing tool, the tiltrotor engineers lost their splendid isolation.
A couple of years before the JVX came along, marketing asked Wernicke’s team for a conceptual design of a tiltrotor big enough to carry twenty-four Marines. A lively debate ensued. The engineers already had a conceptual design for a tiltrotor about the size of the XV-15, just large enough to hold twelve troops. They wanted marketing to sell that. Dick Spivey told them the Marines didn’t care what engineers wanted. The Marines wanted an aircraft that could carry twenty-four troops. Given the limited number of amphibious assault ships in the fleet, the Marines felt they needed an aircraft that size to get enough troops ashore quickly enough in a standard assault. Besides, if they agreed to buy an aircraft that held only twelve troops, others in the Pentagon would surely force them to buy Sikorsky’s UH-60 Black Hawk helicopter. The Black Hawk was just that size, already flown by the Army, and would be cheaper than a tiltrotor. After years of cultivating the Marines, Spivey also thought they were loath to buy the same helicopters as the Army because “the more they got like the Army, the more likely they were to be absorbed into the Army.”
The big-versus-small tiltrotor debate at Bell came to a head in 1980, when some of the engineers tried to convince Atkins that Bell’s first tilt-rotor product should be their twelve-passenger design. At a meeting on the issue, Spivey told them he couldn’t sell a tiltrotor that size to the military. Marketing won the argument. Atkins had favored the bigger machine anyway. He wanted to sell the military a tiltrotor big enough to be adapted to a civilian version holding about forty-four passengers, a machine that might compete with jets for the regional air transport market.
Not long before the JVX program got started, marketing put together a brochure touting a big, sleek tiltrotor that would hold twenty-four Marines and operate from amphibious landing ships. Wernicke paid no attention. He was utterly absorbed by his own engineering work, nearly oblivious to what went on around him. He wouldn’t even open his mail unless someone complained about getting no response. He just let it pile up in the in-basket on the corner of his desk until it leaned like the Tower of Pisa, then tipped it over into the wastebasket. Wernicke only focused on what the military wanted in the JVX when he read the draft specifications the companies got as they were gearing up to bid. When he saw them, he hit the ceiling.
“I went in and told the vice president of engineering, Bob Lynn, that I wasn’t going to do it, that I thought it would be the downfall of the tilt-rotor,” Wernicke told me.
Wernicke believed in the tiltrotor as much as anybody. He’d watched with pride as the XV-15 performed at the Paris Air Show in 1981, beamed when it did its little bow and the audience cheered. He knew he could design a tiltrotor the same size as the XV-15 for the Navy or Marines that would be just about perfect, or even a bigger one for the Air Force or the Army, who wouldn’t want to fly theirs from ships. Long-range transport to and from rugged areas was the ideal tiltrotor mission, he thought, a task where its vertical takeoff and landing ability would be needed but speed and range would be its ace in the hole. As Wernicke saw it, the military was buying this tiltrotor for the wrong mission.
The JVX was to perform a long list of chores for all four armed services, but its main job would be to carry Marines from ship
to shore over distances of no more than about 50 to 110 nautical miles—roughly 55 to 125 statute miles—while flying no higher than 3,500 feet. On such missions, the aircraft would have to take off and land vertically, hover at each end of its flight, and repeat the trip before it was refueled. Wernicke saw that as a helicopter mission, a job for an aircraft that could hover efficiently—that is, using minimal fuel—and needn’t fly high. A tiltrotor could never hover as efficiently as a helicopter because its rotors had to serve as propellers, too. Their dual function was why Bell called them “proprotors.” To work as propellers, proprotor blades have to be shorter than helicopter rotor blades and twisted more to provide efficient thrust in forward flight. The smaller diameter and greater twist of its blades meant a proprotor needed more power than a helicopter rotor to lift the same weight and hold it in the air. A proprotor also wasn’t an ideal propeller—its blades were too long—but it wasn’t a bad one, if configured the right way. That argued against the Marine Corps mission, too, Wernicke thought. A tiltrotor would give the Marines speed all right, but it would give them speed efficiently only at high altitude, where thinner air allows an aircraft to fly faster for less fuel. “A tiltrotor mission is one where you take advantage of the capability . . . to go at high speed and cruise over long distances,” Wernicke said. The tiltrotor’s ideal altitude for flying fast, he calculated, would be way up at 40,000 feet, where the density of the air is about 25 percent of what it is at sea level. No such mission was in the requirements.
The straw that promised to break this camel’s back for Wernicke, though, was the requirement that the JVX be able to operate from a Tarawa-class amphibious assault ship, known as an LHA. An LHA isn’t a small ship. It can carry a complete Marine battalion, their supplies and equipment, a couple of dozen helicopters to get them ashore, and six Harrier fighter jets as well. It has ten “deck spots” for vertical take-offs and landings, and space enough to park a number of aircraft topside while others fly to and from the vessel. But the specs said the JVX had to taxi past the ship’s superstructure with its rotors turning. As it did, the tip of the closest rotor would have to clear the “island,” as it’s called, by no less than twelve feet, eight inches, and the landing gear tires would have to stay five feet from the outboard edge of the deck. Any closer would risk the aircraft rolling over the side. This narrow corridor meant each proprotor could be no more than thirty-eight feet in diameter— smaller than Wernicke knew was warranted for the aircraft’s bulk.
Some on the four-service committee that wrote the basic requirements envisioned a tiltrotor weighing about 20,000–25,000 pounds empty, maybe 4,000 pounds more than the CH-46 the JVX was to replace. But they had underestimated how much all the things they wanted in it were going to weigh. Moved by U.S. helicopter losses during the war in Vietnam, where more than 40 percent of those flown were lost, the panel had written requirements for “survivability” that far outstripped any ever required in a helicopter. “Flight-critical systems” must be either tough enough to withstand hits from 14.5-millimeter armor-piercing incendiary projectiles—the size fired by the largest Soviet-made machine gun of the day—or installed in multiple sets, so that if one was disabled, the extras would keep the JVX flying. The exhaust from the JVX’s turbine engines had to be cloaked from heat-seeking missiles by heavy devices called infrared suppressors. Depending on the mission, the JVX also was to carry “automatic weapons for in-zone suppressive fire and missiles for air-to-air defense,” the requirements said, as well as a long list of special electronic gear. The Naval Air Systems Command engineers who had written the detailed specifications were more realistic than the four-service committee that drafted the mission requirements. Navair set an upper limit of 31,886 pounds on the JVX’s “weight empty,” how much it would tip the scales without any fuel, pilots, passengers, or cargo aboard. Wernicke could see right off the bat, though, that with its big fuselage, with mechanisms to tilt its engines and rotors, with still more mechanisms to fold its rotors and stow its wings, plus all the other requirements, this bird probably was going to weigh a lot more than that. Moreover, its normal flying weight—what engineers call “design gross weight”—would surely be well north of 45,000 pounds. The military’s great expectations were bordering on mission impossible.
All aircraft designs involve compromise. Size, speed, range, and so forth have to be traded off against one another and balanced to meet the requirements for the aircraft being created. A fundamental question for the designer, however, is how heavy the aircraft will be, for weight dictates how much power is needed to lift a machine into the air and carry a useful load. When a rotorcraft takes off straight up or hovers, it has to produce a pound of thrust for every pound it weighs, plus enough to compensate for whatever portion of its rotor downwash pushes down on the fuselage and other parts of the machine. How much horsepower is needed to produce that thrust determines a rotorcraft’s “hover efficiency,” meaning how much lifting power it actually gets out of the horsepower its engines generate. Hover efficiency affects fuel consumption and thus operating cost.
One way to determine how much horsepower will be needed in a rotorcraft is to calculate its “disk loading.” The “disk” in question is the area of the circle described by a rotor’s blades. The “loading” is how much thrust the disk must create to lift the required weight. A bigger rotor moves more air over a larger disk area than a smaller rotor, and thus requires less energy—less horsepower and fuel—to generate an equal amount of thrust. Disk loading is expressed in pounds per square foot and calculated by dividing the machine’s normal flying weight—its design gross weight—by the area of the disk. The larger the disk area, the lower the disk loading. Other things help determine hover efficiency, but in general, the lower the disk loading, the less power required to lift the aircraft and keep it hovering.
Most helicopters have disk loading of four to ten pounds per square foot. Thanks to its small rotor diameter and heavy weight, the JVX’s disk loading was going to be an uncommonly high twenty pounds per square foot or more. Such high disk loading raised a number of questions, some of which would spark hot debates years later. For now, though, what worried Wernicke most about the limit on rotor size was that it would necessitate increasing the JVX’s weight. Smaller rotors and high disk loading meant the aircraft was going to need beefier engines than if its rotors could have been sized for its weight rather than to fit on the ship’s deck. More powerful engines would be bigger; bigger engines would be heavier; bigger, heavier engines would need bigger, heavier transmissions. Nor did it stop there. As an aircraft gets heavier, it needs stronger internal structures, and stronger internal structures usually add more weight. A heavier aircraft also needs more fuel to fly; more fuel means more weight. Extra fuel may require extra fuel tanks, and extra fuel tanks mean extra weight. And so on. Pretty soon, things get to a point where the designer can’t “close the design loop,” as engineers put it. There’s so much aircraft to lift that insufficient room is left for the payload the machine was being designed to haul. Wernicke thought the JVX was close to that point at conception.
“I thought from the git-go that it was going to be so heavy that there wouldn’t be enough useful load for the price of the aircraft to make it cost-effective,” he told me.
That was why, after he studied the specs, Ken Wernicke went to Bob Lynn, Bell’s senior vice president for engineering, and told him he just wasn’t going to do it, he wasn’t going to design this JVX. It was going to be too complicated, too heavy, and too costly. It was probably going to discredit the tiltrotor forever.
Lynn talked Wernicke into it.
“He said there was no one else who could do it and I should do it and it was the only game in town,” Wernicke recalled. “Of course, I knew it was the only game in town.”
* * *
Lynn apparently wasn’t shocked or dismayed by Wernicke’s threat to boycott the project. Years later, he said he didn’t remember it, though Lynn didn’t doubt Wernicke’s
recollection. “He was like that,” Lynn said. Everyone knew Ken Wernicke was irascible much of the time and impassioned about the tiltrotor always. It was his dream machine. Wernicke also had a “build it and they will come” notion of marketing, as Lynn saw it. Lynn and others at Bell and Boeing Vertol didn’t underestimate the challenges the JVX posed, but they were more pragmatic. Unlike Ken Wernicke, his bosses had dealt with the Pentagon for years. Stanley Martin, Jr., a vice president under Lynn and Wernicke’s supervisor in those days, was among them. “Some of us had learned that you do what your customer wants, you don’t try to tell your customer what he wants,” Martin told me.
Besides, the military often issued unrealistic requirements for big procurements, in part to spur industry on to greater heights, in part because the officers who wrote the requirements could be poor judges of what was possible, in part to justify starting a new program. After all, some reasoned, if what the military wants to build isn’t going to be a lot better than what it already has, the Pentagon’s civilian leaders and Congress might refuse to fund it. When it came to writing requirements, the services always asked for the sky and contractors always told them they could deliver it “by yesterday” and priced to “sell at the ten-cent store,” in the words of the Al F. Davis poem. That was why stories on outrageous schedule delays and cost overruns were a staple for reporters on the Pentagon beat. Development schedules and cost estimates for major military hardware—especially aircraft—were almost always ridiculously optimistic. The incentive on both sides, for the military and for the contractors, was to shoot for the moon and worry later about how much they were going to miss it by.
The Dream Machine Page 15
