When Schriever had relieved Hall as program director for Thor in the summer of 1957 after that missile’s third failure and Hall’s alienation of his co-workers, he had shrewdly avoided firing Hall from his staff and thereby losing his unique talents. Hall, in anger at his dismissal, had requested a transfer out of WDD. Schriever had refused. Instead, he had set Hall to work creating a second-generation ICBM. As all earlier liquid-fueled rockets had been descendants, in one form or another, of the German V-2, so this new guided missile was to be the progenitor of all rockets to follow. Hall’s rocket was to be fueled by a solid substance rather than by RP-1 kerosene and the dangerous and highly volatile liquid oxygen that powered the first generation. If a solid-fueled ICBM could be devised, it would have a number of advantages over its liquid-fueled predecessors. It would be much smaller and far simpler in construction, thus making it more reliable and affordable for the United States to produce in many hundreds. It could be stored in full readiness for lengthy periods of time. And most important, it could be fired off on its journey through space in a minute or less.
Ed Hall had long had a yen to build a solid-fuel ICBM. Apparently understanding that this missile was the work for which he would be remembered, once over his pique about Thor, he dedicated himself to his task with a ferocious zeal. He had formidable obstacles to overcome. To begin with, he had to devise a solid fuel that would develop enough thrust, called “specific impulse” in the rocket business, to propel a warhead 6,330 miles. Hall had already dabbled in solid-fuel rocket work. At the beginning of the 1950s, he and his associates at the Wright-Patterson laboratories had improved on the small solid-fuel rockets Theodore von Kármán and his colleagues at the Guggenheim Aeronautical Laboratory at Caltech had invented during the Second World War to give aircraft a quick extra lift during takeoff. Hall’s group had created a solid fuel potent enough to assist in getting a fully loaded B-47 aloft, but it did not approach what he needed now. He had also made considerable progress during a research study of solid-fuel engines Schriever had authorized at WDD in 1955 and 1956, but again a formula for the right fuel had eluded him.
The Navy, anxious to get into the strategic rocket business, had by 1957 also abandoned the batty idea of launching a Jupiter missile from the deck of a ship, a spectacular way to burn and sink the vessel if the liquid-fueled rocket malfunctioned, and was working up a solid fuel, submarine-launched missile that became Polaris. While the Navy was willing to swap ideas, its research was of little assistance to Hall. Polaris was to be an IRBM with a 1,380-mile range. Hall was searching for a solid fuel with a lot more thrust than Polaris would require. He selected the three firms he considered most promising, Thiokol Chemical Corporation, Aerojet General, and Hercules Powder Company, and began experimenting. Hall and the team working under him finally hit on a formula that provided the necessary power. It was a lot more exotic than liquid oxygen and kerosene. They used a chemical called ammonium perchlorate to provide oxygen for the rocket’s flame, and as fuel aluminum additives and a combination with a long name, polybutadiene-acrylic acid. The whole propellant was compounded together and encased in a rubberlike wrapper that also burned.
One of the persistent problems in creating solid-fuel rockets was getting the fuel to consume itself evenly from the center to the outside casing of the engine, but without burning a hole through the casing and thereby destroying the integrity of the engine and causing an explosion. Ideas, particularly technological breakthroughs, have a way of traveling. In this instance, the Rocket Propulsion Department of Britain’s Ministry of Technology had discovered a solution earlier in the 1950s while experimenting with a solid-fueled antiaircraft rocket. If a star-shaped cut was made all the way down through the middle of the solid fuel, or the same thing was achieved by casting the fuel in a mold with a star shape at its center, then enough burning surface was obtained so that the propellant burned evenly from the center outward, consuming itself in the process and leaving the engine casing intact. The British never went beyond the laboratory with the technique because the missile was canceled. Thiokol was then a small company in Huntsville, Alabama, near the Redstone Arsenal. When the Air Force asked Thiokol to build a solid-fuel rocket of modest size to provide a preliminary boost for a jet-powered cruise missile of 700-mile range called the Mace, Thiokol helped itself to the British idea. The star-shaped cut turned out to be equally applicable to Hall’s far more powerful solid-fuel engine.
The next hurdle was how to achieve instant shutdown of the engine, that absolute necessity for accuracy in a ballistic missile. This was not difficult with liquid fuels because the flow could just be cut off. But once a block of solid fuel had been set alight and was driving a rocket at thousands of miles an hour, how was one to extinguish it in flight? Some of the Ramo-Wooldridge engineers thought the problem insoluble. Hall came up with an elegantly simple answer. He designed an engine casing with shutdown ports. When the missile’s control system flung these open with a signal, the pressure inside was reduced so swiftly that the propellant was snuffed out. Steering was to be achieved with equal simplicity, by swiveling the engine nozzles. Hall designated his creation, which had not yet been given its permanent name, Weapon System Q. He chose Q because he discovered that the majority of the remaining letters of the alphabet had already been co-opted by other departments, and projects of WDD and Q had an element of mystery and surprise for him. It called to his mind the Q-ships, merchantmen with disguised depth charge mounts and false sides that hid cannon, which the British navy had employed during the First and Second World Wars to lure and destroy German submarines. He believed that his new weapon and the plan he had conceived to employ it would also surprise.
By January 1958, he was ready to unveil it. He telephoned Schriever’s deputy, Terry Terhune, and said that he needed several hours of Terhune’s time to brief him. Colonel Terhune told Hall to come to his office right away and instructed his secretary to cancel his appointments. Hall held forth for two to three hours. He had a blueprint of the proposed new rocket and went step by step through its advantages over its liquid-fueled predecessors, as well as his plan on how to deploy it. Terhune was so impressed that he led Hall over to Schriever’s office and said that he had to hear Hall immediately. Schriever in turn canceled his appointments and Terhune sat by while Hall launched into another two-to-three-hour briefing session. As soon as Hall was done, Bennie picked up the phone and called Lieutenant General Donald Putt, currently deputy chief of staff, development, at the Pentagon. He informed Putt that they wanted to come to Washington around the end of the month to brief him. He also asked Putt to set up briefings with the Air Force Council and with James Douglas, Jr., the new secretary of the Air Force, who had replaced Donald Quarles the previous May. In the meantime, Hall was to prepare charts and any other aids necessary for a full-scale presentation.
As Schriever and Terhune both had their families living in Santa Monica, they rode to and from work together each morning and evening when Schriever was not in Washington or at Canaveral. Terhune welcomed the custom as an opportunity to alert the boss to forthcoming problems, have him read over a proposal on which Terhune wanted his opinion, or just review the events of the day. Because Schriever was away so much and trusted Terhune completely, he had become, in effect, supervisor of the California end of their endeavor. With the Pentagon briefings in prospect, they thought it was time to give Q a catchier name, one that might help to sell the missile. Hall and others had already proposed three alternatives: Sentry, Sentinel, or Minuteman. Schriever and Terhune decided that the last most aptly caught the essence of the new rocket and so Minuteman went to Washington.
As matters turned out, the Pentagon briefings were postponed until the beginning of February. The first crucial briefing was on February 6, 1958, before the Air Force Council. Curtis LeMay was now vice chief and thus its chairman. They did not expect trouble from Thomas White, who had become chief of staff in July 1957 when Nathan Twining had moved up to become chairman of the Joint Chiefs, because White had been so supportive of the ICBM program from the outset. LeMay had remained unremittingly hostile to Atlas and Titan. “These things will never be operational, so you can depend on them, in my lifetime,” he had predicted to Jerome Wiesner, the Tea Pot Committee veteran. Nevertheless, Schriever had felt it his duty, as the ICBMs would ultimately be turned over to SAC, to keep LeMay informed. He had always been rewarded with scorn. The Cigar had sat silently through one briefing on Atlas. At the end he had asked, “What is the biggest warhead you can put on that missile?” One megaton, he was told. “When you can put something on that missile bigger than a fucking firecracker, come and see me,” LeMay replied.
If he reacted in the same fashion to Minuteman, they would have a fight on their hands, because, while White would, in the end, probably rule in their favor, he would be reluctant to just brush aside his subordinate’s opinion. Schriever introduced Hall in a couple of sentences and then turned the briefing platform over to him and sat down. Terhune remembered the self-confidence with which Hall spoke and the skill with which he employed his blueprints and charts to illustrate his points.
Solid fueling had enabled Hall to shrink an ICBM. The Minuteman he described would be a small boy compared to an Atlas or a Titan. It would weigh, including its solid propellant, about 65,000 pounds at liftoff, compared to 243,000 pounds for Atlas, and would stand approximately fifty-five feet tall, in contrast to ninety feet for Titan. Yet he had sacrificed none of the reach and potency of the ICBM weapon. His rocket was a three-stage affair, each stage smaller and lighter than the last. Stage I, at 50,100 pounds, would provide liftoff and bring the rocket to initial velocity. As it shut down and fell away, the engine of Stage II would kick in and increase speed. Then as it too went silent and dropped off, the engine of Stage III, which weighed only 5,800 pounds, including the solid fuel, the missile’s guidance system, and the ablative-type reentry vehicle at the nose with a one-megaton hydrogen bomb inside, would ignite and propel the rocket to terminal velocity for release of the warhead. Nor would there be any scrimping in range. Minuteman would throw its warhead the same 6,330 miles as Atlas and Titan with a CEP, circular error probable, of little more than a mile.
There was a proviso on warhead yield, Hall said. The nuclear weapons designers would have to size a one-megaton bomb down to 500 pounds. Given the rapidity with which the art of downsizing hydrogen weapons was progressing, Hall said, he did not doubt that this could be done by the time the first Minutemen began to flow to an operational squadron. Schriever and Terhune agreed. If the Air Force was willing to settle for a half-megaton warhead of 350 pounds, the Minuteman’s range could be extended to a record 7,480 miles. (The nuclear weaponsmiths were indeed displaying an astonishing aptitude for miniaturizing their hellish contrivances. When deployed, Atlas and Titan I would both carry thermonuclear warheads yielding four times the one megaton Schriever had counted sufficient at the outset back in 1953, with no appreciable gain in weight beyond the 1,500-pound limit. The first 150 Minutemen were to be fitted with a one-megaton warhead and those that followed with a higher-yield bomb of 1.2 megatons.)
Hall’s scheme for deploying Minuteman was as radical as the weapon itself. His design, he explained, was intended to deter the Soviets from ever resorting to a surprise nuclear attack on the United States. His plan was to build 1,616 Minutemen (the total included spares) by the end of calendar year 1965 and to deploy them in “missile fields” of one hundred or so. The rockets would be dispersed three miles apart, every one in an underground silo sufficiently hardened with concrete and steel so that if the Soviets hit the field with a five-megaton warhead, only one rocket would be lost. The silo covers would then slide open and the remaining Minutemen would be launched right out of the silos in retaliation. Because of their solid fuel, the rockets could be stored in the silos indefinitely. They would be checked constantly to be certain that every one was in working order and that the inertial guidance systems, internal to the missiles and therefore unjammable, were always up and running. If a malfunction was found, the missile would be removed from its silo and replaced by a spare until it could be repaired. Everything would be automated. Unlike the liquid-fueled ICBMs, which had to be launched individually after fifteen minutes of fueling, two or more remote control centers, also dispersed for survival, could fire individual Minutemen or salvo fifty at once, each with the coordinates of a different Soviet city cranked into its inertial guidance. The Russians would, of course, learn of the missile fields and the virtually instantaneous launch capability of Minuteman and draw the appropriate conclusion.
LeMay had written Twining back in November 1955 that he would consider the ICBM “the ultimate weapon” worthy of inclusion in SAC’s inventory when one could be created “with a capability of instantaneous launch and with acceptable reliability, accuracy, and yield.” The conditions were technological pie in the sky at that time, an attempted stalling tactic, because LeMay knew that the technology of nearly instantaneous launch was years away, if ever, and at this moment in 1958 he continued to regard the bomber as the best of weapons. But he also turned out now to be as good as his word on what he required in an ICBM. Terhune remembered that after a short discussion at the end of Hall’s briefing, LeMay swung around to the three-star deputy chiefs of staff sitting in the rows behind him and asked: “Do you agree it’s a go?” They all did. Hall got the impression that what appealed most to LeMay was the massiveness of the scheme. The thought of hundreds and hundreds of rockets roaring out of silos was LeMay’s vision of how to frighten the Russians and then to reduce the Soviet Union to cinders if it did come to nuclear war.
The briefing for Air Force Secretary Douglas was also a go, and on the morning of February 8, 1958, they faced the last hurdle: a briefing for Wilson’s successor, Neil McElroy. LeMay came as well as Douglas and, to Hall’s surprise, LeMay weighed in with comments underscoring Hall’s briefing points. McElroy gave his assent. The meeting ended, Hall recalled, with the secretary turning to him and saying: “Now get out of here and go back to work.” After they had returned to California, Terhune found himself astonished at what they had accomplished. They had been in Washington only a few days and had won approval for what would probably be the biggest rocket program the Air Force would ever undertake. “That was a world’s record as far as I was concerned,” he reflected years later. Schriever had Hall draw up a detailed development program and by the end of February they had formal approval and start-up funds of $25.9 million. Hall forged ahead toward a final design. By the latter half of July 1958, he had reached the point where the contractors who would build the missile had been selected.