Godel had no way of knowing that just two years earlier DARPA had started a secret study looking at ways to use technology to help overcome the Soviet conventional advantage, but he was clearly aware of the strategic debates at the time. President Nixon’s pursuit of détente with the Soviet Union and associated negotiations for nuclear reductions had also brought renewed debate over the Warsaw Pact’s conventional advantage in Europe.
Godel’s prescience about the concept of a stealth aircraft was based on his understanding of the political and military situation in Europe as much as technology: he knew that penetrating Soviet air defense was a strategic imperative, just as global counterinsurgency had been in the early 1960s. Godel had always believed that DARPA’s role had to be guided by strategic planning, which required understanding current problems but also looking ahead at future threats. That had been a view supported by the first three scientists to serve as the Pentagon’s director of defense research and engineering. Herbert York, John S. Foster, and Harold Brown, all physicists and former heads of Livermore Laboratory, had supported an expansive role for DARPA that bridged strategy and technology.
Malcolm Currie, on the other hand, was closer to the world of engineering and defense contracting. The engineer had risen to be a vice president of research at Hughes Aircraft before moving over to the Pentagon. He viewed DARPA as the Pentagon’s industrial lab and was irritated by anything he saw that smacked of policy or strategic planning. And despite his enthusiasm for the idea of a stealth aircraft, Currie was not happy with DARPA, or at least not with Lukasik, its director. Lukasik was traveling around the world discussing arms control, he was sponsoring studies on military strategy, and then there was the parapsychology investigation. Currie decided that Lukasik, by then the longest-serving director of DARPA, needed to go. The pick to replace him was George Heilmeier, an engineer from RCA, who was working for Currie in the Pentagon. Heilmeier had already distinguished himself as the father of the liquid crystal display, a technology that would eventually be used in everything from cockpit displays to home alarm clocks. Perhaps because of their mutual background in industry, Currie and Heilmeier “clicked.”
The new DARPA director brought immediate changes. Heilmeier believed Secretary of Defense James Schlesinger wanted DARPA to go back to its roots, or at least what Schlesinger believed were its roots. “He wanted more technology there,” Heilmeier said. “He didn’t want a lot of work done in foreign policy by a technical agency.” Lukasik had allowed DARPA officials unprecedented freedom. DARPA orders, the brief summaries used to authorize new programs, were unimportant to Lukasik, and he rarely if ever read them. Heilmeier, on the other hand, pored over every word of the orders, often sending them back for revisions. He also began to comb through the budget, weeding out programs he felt had limited relevance to the military.
J. C. R. Licklider, whose vision of an “Intergalactic Computer Network” had been enthusiastically embraced by the likes of Herzfeld and Lukasik, suddenly found himself in conflict with DARPA’s new director. The soft-spoken Licklider had returned to DARPA in 1974 but found himself facing a director who did not share his broad vision of computer science. “When I looked at the so-called proposals I thought, ‘Wait a second; there’s nothing here,’ ” Heilmeier said. “It was just, ‘Give us the money and we will go do good things.’ ”
Heilmeier wanted to know how research would help a tank operator. He wanted a way of translating Morse code. He wanted a way of working with a pilot. Computer scientists protested that creating artificial intelligence was not like building an aircraft that was set to fly on a specific day, but in Heilmeier’s view it should not be any different. Scientists were aghast that they now had to write proposals with specific goals in mind. “That’s pure bullshit,” he said. Licklider left DARPA for a second time, not long after Heilmeier came on board.
Heilmeier was convinced that any Pentagon support for science had to be aimed at developing a specific technology that could be used by the military. A good part of his philosophical approach to technology came from his time at RCA, where he felt the company had failed to recognize—and take advantage of—his invention, the liquid crystal display. He knew from personal experience that it was not enough to come up with an innovative technology; there needed to be a plan to take that technology to market, whether in the commercial world or with the military. He looked at his job as akin to a venture capitalist who invests in high-risk technologies but only those that meet a set of criteria. Heilmeier created a series of questions that he called the “catechism,” which he made the litmus test for any program brought to his office:
First what are you trying to do?
How is it being done now, and what are the limitations of current practice?
What’s new in your approach?
Why do you think it can be successful?
If you are successful, what difference does it make?
How much money does it need, and how long is this going to take?
What are the midterm and final exams?
Coming from the private sector, Heilmeier had little interest in science for the sake of science. He admitted there was resistance to his view, particularly from DARPA-funded researchers who had not needed to justify their work in the past in terms of an immediate military application. “Why don’t you try to perform an impossible sexual feat?” Heilmeier said was his response to them.
While a stealth aircraft might sound like an ideal program for a new DARPA director interested in advanced military technology, Heilmeier was initially skeptical when he called in Moore to review the Tactical Technology Office’s portfolio. The new director was housecleaning, and he made it clear that Moore’s programs, and even his job, were far from guaranteed. “He went through all my programs and after he finished all the other reviews, he called me into his office and told me that the only program he found questionable was the stealth aircraft,” Moore recalled.
Heilmeier said he did not see how an aircraft that could evade Soviet radar involved any advanced technology. Prior to becoming director of DARPA, he had listened to Myers talk about the Harvey concept, which was actually very different from what DARPA was proposing. Myers was advocating for a modestly priced aircraft with a reduced signature that would fly in the Fulda Gap to assist other, more capable fighters. The idea of the aircraft being “invisible” was hyperbole; Harvey was not an aircraft that would be undetectable to all enemy radar, just less visible than other aircraft. Moore’s idea for the high stealth aircraft, on the other hand, was for something more ambitious—an aircraft that could slip past Soviet radar completely unseen.
Moore argued to Heilmeier that the DARPA concept of stealth was something that would affect the entire design of the aircraft. It was not just about making a tweak here or there, as had been done with the small drone. DARPA was proposing a new type of aircraft that would make the radar cross section as low as the physics would allow while accepting whatever aerodynamic design that required—so long as it could still fly. This was not Harvey but a radically new aircraft. Heilmeier listened closely, but Moore was convinced the invisible aircraft was dead.
Heilmeier might have been skeptical about an invisible aircraft, but Harvey had another patron. Currie, Heilmeier’s boss, had also been on the receiving end of the Harvey briefings, and he was enthusiastic about stealth. A meeting among Moore, Heilmeier, and Currie settled the matter; Currie liked it, and he was Heilmeier’s superior and mentor. “We needed to penetrate enemy air defenses,” Currie recalled. “If we could do that and essentially nullify the radar threat against us, then that was an obvious thing to do.”
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Back in the Pentagon, Myers was still preaching his Harvey concept when Russ Daniel, a Lockheed engineer at the company’s Skunk Works division, dropped by his office. Lockheed had never been contacted by DARPA when Perko was canvassing companies on possible interest in a stealth aircraft, because Lockheed at that point did not build fighters. Daniel reported ba
ck to Ben Rich, the new head of Lockheed’s Skunk Works, about the missed opportunity. It turns out, around the same time, that Rich also found out about the stealth aircraft from his resident Soviet weapons expert, Warren Gilmour, who had gotten wind of the DARPA project from a friend at Tactical Air Command. “Ben, we are getting the shaft in spades,” Gilmour told Rich.
What DARPA did not know was that Lockheed had been secretly working for the CIA on stealthy aircraft designs for years, first with Project Rainbow, an attempt to make the U-2 high-altitude spy plane less visible to radar. The experiment failed, killing a pilot in the process, but the company had more luck with the CIA’s A-12 reconnaissance aircraft, the precursor to the air force’s supersonic SR-71. The A-12 was not a true stealth vehicle, but the “cobra shaped” aircraft, as Rich called it, had been built with radar-absorbing material, a closely held secret. Even so, the improvements were modest; the radar signature was roughly that of a single-engine Piper Cub. In other words, the A-12 still looked like an aircraft when picked up by radar, albeit a small one.
Rich wanted in on the stealth competition, but Lockheed was in a bind. Kelly Johnson, the legendary leader of the Skunk Works, had just retired; he had made his reputation with projects like the U-2 and the SR-71. Rich was desperate to make his own mark. “This was exactly the kind of project I was looking for,” the Skunk Works president recalled in his memoir. “But we had been overlooked by the Pentagon because we hadn’t built a fighter aircraft since the Korean War and our track record as builder of low-radar-observable spy planes and drones was so secret that few in the Air Force or in upper-management positions at the Pentagon knew anything about them.”
Johnson, who was still working for the Skunk Works as a consultant, persuaded the CIA to let Lockheed give DARPA details about the company’s stealth work. The CIA agreed and Lockheed sent a briefing to DARPA and asked for the chance to compete for the stealth work. George Heilmeier warned Rich there were no funds left to pay Lockheed for its participation, but DARPA would at least consider the company’s proposal. Rich was undeterred, and asked to brief Perko, the DARPA official in charge of stealth.
“We want to be part of this study,” Rich told Perko, after giving his stealth briefing.
“We don’t have any more money,” Perko replied apologetically. “We’ve spent all our money.”
Rich then made an offer DARPA officials could not refuse: Lockheed would do the study for the grand price of $1, and the Skunk Works would cover the rest of the costs. It was an expensive gamble, but Rich sensed that stealth aircraft could be the project that would make his name and keep the Skunk Works in the good graces of Lockheed’s executives.
Perko agreed to the offer and, as legend had it, reached into his pocket and pulled a dollar out, and the two men shook hands on the spot. Lockheed was in the stealth competition.
The new DARPA director was also now on board, but he agreed to fund two prototypes of the stealth aircraft only if the air force would pay half the costs. A prototype aircraft would be an expensive endeavor, and even if it were successful, it would not do anything more than collect dust in an aviation museum if someone in the military was not willing to buy it. The prototype was going to cost $50 million, and Heilmeier wanted the air force to pay 49 percent of the costs, leaving DARPA with 51 percent and control over management. Considering the air force’s steady opposition to Myers’s efforts to market Harvey, it did not look promising.
Pilots ran the air force, and pilots want to fly combat aircraft. The idea of an aircraft that would be “invisible,” at the expense of maneuverability and performance, was not immediately appealing. The air force had been dubious of stealth claims, and even when the DARPA studies showed that a stealth aircraft was possible, the air force’s leadership did not see the point: Why field an aircraft that was aerodynamically unstable? Worse, a stealth aircraft would compete in the budget with the air force’s top priority, the F-16 fighter. When DARPA officials first briefed Alton Slay, then a three-star air force general in charge of research, his response was not just no, but hell no. The air force was not interested in spending its money on a DARPA project. Currie, a fan of the stealth project, offered a deal. At a breakfast with General David Jones, the air force chief of staff, he laid his cards on the table: “I will support your lightweight fighter in Congress with everything I’ve got if you will establish stealth as a real air force program and put some money behind it and let us go to Congress with that.” Jones agreed and the two men shook hands.
Shortly after the breakfast, Currie, along with DARPA’s Heilmeier, Moore, and Perko, attended a meeting with General Jones and General Slay. At that point, no one except Currie and Jones knew about their agreement, and Jones was “like the inscrutable sphinx” as the DARPA officials briefed the invisible aircraft program. At the end of the briefing, Jones, sitting at the end of a long oval coffee table, announced, “The air force ought to support this program.” He then turned to Slay and asked him what he thought. Slay replied, “Well, to be against that would be like being against motherhood.”
Stealth had triumphed, not necessarily on a persuasive argument about the technology, but through a handshake deal. The air force kept its commitment, Slay’s prior opposition to the stealth aircraft evaporated, and DARPA officials later credited him with being an avid supporter. “You have to admire a man that when he’s ordered to do something, he didn’t pull any punches,” Heilmeier recalled. “He did it.”
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The idea of designing aircraft to be less vulnerable to Soviet air defense systems was not new; it was just incredibly hard. Military engineers had experimented with ways to make aircraft harder to detect since the advent of radar during World War II. The problem was an exponential one, meaning that even large reductions in radar cross section translated into quite modest advantages when it came to evading detection. For example, if American engineers wanted to reduce by half the range at which Soviet radar would pick up an incoming bomber, from twenty minutes to ten minutes, they had to reduce the radar cross section by a factor of sixteen. And even that was not nearly enough for a strategic advantage.
In most aspects of aviation, even a 10 percent improvement in performance would be fantastic, but in the world of low observables, the technical term for stealth, a 50 percent reduction does not translate into much military capability if the aircraft is, for example, trying to slip past Soviet air defense radar. Even if the radar cross section were cut in half, the aircraft would still be picked up by enemy radar in time for it to be shot down. “The difference for the Soviet guys is they no longer will have the leisure to talk about whether the Moscow Dynamos is the better football club than Kiev, or will they necessarily finish up their cup of coffee,” Alan Brown, Lockheed’s chief engineer at the time, joked. “But they still have all kinds of time to call up the surface-to-air missile systems and the airfields and say, ‘Go and get those guys, they are ten minutes away.’ ”
In other words, if engineers wanted to reduce the range of detection for an aircraft by a useful amount, say by a factor of ten, they would have to reduce the radar cross section by a factor of ten thousand, something that key air force officials deemed impossible. Tweaking the designs of existing aircraft would not yield that sort of reduction; it would require a total redesign, and most designs suitable to stealth were not very suitable to flight. As Kelly Johnson, the former head of Lockheed’s Skunk Works, noted early in development, the shape best suited for stealth was something that resembled a flying saucer. Short of antigravity technology, a flying saucer was not likely to make for an effective aircraft.
Lockheed might have joined the stealth contest late, but it started with a strong advantage because of its aviation work for the CIA on projects like the U-2. Its other advantage was that the Skunk Works division operated a bit like DARPA, meaning it was flexible, had minimal bureaucracy, and could quickly assemble a team of experts for a particular project. One of those experts was Denys Overholser, a young electrica
l engineer and mathematician. Previous attempts to design aircraft to avoid radar put aerodynamics first, while making it stealthy was an afterthought. As a mathematician rather than an aerodynamicist, Overholser took an entirely different approach to the idea of a stealth aircraft. Instead of thinking about what made for an effective aircraft, he looked primarily at ways to design something that would reflect radar. He suggested designing the aircraft in a series of flat panels that would be arranged in such a way so as to ensure the radar’s energy was deflected away from the source, and thus could not be easily detected. The panels gave the aircraft a distinctive faceted design and a decidedly un-aerodynamic shape.
Overholser had settled on that design because, in 1974, he could create a computer program to calculate the return for those flat panels based on physical optics but not for something extremely complex, like curves. He also could not estimate what happened on the edges of those panels. That is, until he stumbled across an unclassified Russian scientific paper that had been translated by the U.S. Air Force Systems Command’s Foreign Technology Division, which regularly combed unclassified Eastern bloc scientific literature for work of interest to the military. The translation of the Russian scientist Petr Ufimtsev’s paper “Method of Edge Waves in the Physical Theory of Diffraction” had gone unnoticed for several years until Overholser realized that it could help him calculate the radar cross section for the edges of the panels. Brown, Lockheed’s chief engineer, estimated that Ufimtsev’s theory contributed about “30 percent” to Lockheed’s stealth calculations. “It wasn’t like the Russians saved us,” Brown said.
The Russian’s formulas might not have helped immediately, but they clearly emboldened Overholser, who argued that flat panels would allow the engineers to predict the radar cross section. The resulting design, created to test stealth and not its ability to fly, was faceted like a diamond and shaped like a sort of swept-back pyramid. “Well, that’s stupid. We’ll never make that fly,” was the reaction from Lockheed’s designers, recalled Brown. “They christened it the Hopeless Diamond.”
The Imagineers of War Page 29