The Missile Race Begins
v1.1.1 / chapter 4 of 26 / 01 apr 13 / greg goebel / public domain* The chill of the Cold War arrived in earnest in the early 1950s. With improvements in technology -- lighter and more destructive nuclear weapons, refined guidance systems, and increasingly capable rocket technologies -- the long-range missile became a possibility. The US and the USSR quickly found themselves in a deadly race to develop a strategic missile force. The loser of the race faced the prospect of complete destruction.
[4.1] US CRUISE MISSILES / NAVAHO
[4.2] PROGRESS IN SOLID FUELS
[4.3] ATLAS EMERGES
[4.4] BUILDING ATLAS
[4.5] TITAN, JUPITER, & THOR
[4.6] POLARIS
[4.7] TRIAL AND ERROR
[4.1] US CRUISE MISSILES / NAVAHO
* By the early 1950s, the US military had a number of development programs for long-range cruise missiles in progress. The US Army worked with Martin on a cruise missile named "Matador"; the Navy worked with Vought to build the "Regulus" for launch from submarines or ships; and the Air Force worked with Northrop to build the "Snark". All these weapons had ranges of a few hundred kilometers, though Vought would go on to develop a Mach 2 "Regulus II" with a range of a few thousand kilometers, and Northrop would develop the "Super Snark", with true intercontinental range.
Cruise missiles were just robot aircraft, much more straightforward from a propulsion and aerodynamics point of view than a long-range rocket. The real problem was the guidance system, and though major investments were made in the technology, building an accurate missile guidance system was a tough job. The Super Snark program was particularly troublesome. They were tested off the Florida coast, with so many of them ending up in the sea that program workers started to talk of "Snark-infested waters". One Super Snark decided to take a tropical vacation while on flight test, and disappeared to regions south. There must have been anxious moments among the flight test team over where the thing would end up, but it simply disappeared -- to be found lying in a Brazilian jungle in the 1970s.
* The Matador, Regulus, and Snark were no faster than contemporary jet aircraft, and so were relatively easy to shoot down. The Air Force began to consider a more impressive cruise missile, named "Navaho", that would have much higher performance.
The Navaho was more or less the brainchild of William Bollay of North American Aviation (NAA). Bollay's parents had emigrated with him from Germany in the 1920s, and in the 1930s he got a scholarship to Caltech. He fell in with von Karman and Malina, though he focused his studies on conventional aircraft design, since he wasn't inclined to bet his future on rockets at the time. When the war came, he enlisted in the Navy, working for Robert Truax on turbojet engines. In 1945, with the end of the war, he mustered out of the service and went to Los Angles, California, to work for NAA. By this time, there seemed to be more of a future for rockets, and Bollay began to work on rocket-engine design for NAA. He managed to pry a few of von Braun's people loose from White Sands and began to work on uprating the V-2's engine.
The V-2's rocket engine was the most powerful in the world at the time, but there was obvious room for improvement, for example in fuel injection. The early German A-3 rocket had a small engine, featuring a "burner cup" where alcohol was squirted in from one side and liquid oxygen from the other. That was fine for a small rocket engine, but the burner cup couldn't be so easily scaled up to a large engine, since the propellant flow was greater and mixing was a problem. The V-2's engine had used 18 burner cups, resulting in a "plumber's nightmare". A better fuel-injection system would resemble a high-volume shower head. The Germans had tried to develop such a scheme during the war, but ran out of time.
Bollay took up where the Germans left off. In 1947, NAA leased land at Santa Susanna Pass in the mountains to the east of Los Angeles and began construction of a new rocket test center for the development of the new rocket engine. The company was in difficult financial circumstances due to the postwar military cutbacks, but rockets looked like a good investment. The rocket group would become the NAA "Aerophysics Laboratory".
In the meantime, Bollay had come up with a new proposal for a long-range missile for the Air Force. He envisioned something like a V-2 with wings, with ramjet engines for cruise flight. A ramjet was little more than a stovepipe with fuel injectors and an ignition system, effectively an air-breathing rocket engine. Ramjets offered high thrust, though they had to be moving at high speed before they could be properly ignited.
NAA named the project "Navaho". In the original concept, the Navaho would take off on its own rocket engine and then cruise at high speed and altitude on its ramjets. This scheme provided high performance, but was not as great a technical challenge as was a true rocket-powered intercontinental missile. Bollay figured that Navaho would have a range of about 1,600 kilometers (1,000 miles). The Wright Aeronautical Company was to build the ramjets, while Bollay focused on the rocket engine.
Bollay worked with the USAF to determine that an engine providing the 334 kN (34,000 kgp / 75,000 lbf) thrust was required. That was only about 34% more powerful than the V-2's engine and seemed easily achievable. However, the rocket engine development program ended up spinning its wheels. The effort needed more professional management, and in 1949 Bollay brought in Sam Hoffman, a Penn State aerodynamics professor who Bollay had worked with during the war. In March 1950, the group ran its first static engine test. The engine blew up with a spectacular explosion.
By that time, Navaho had evolved into a two-component system, consisting of a big liquid-fuel rocket booster that carried a dartlike ramjet-powered cruise missile to high altitude and speed, striking targets across oceans. This was a bigger vehicle and it required bigger engines. Bollay intended the rocket booster to be fitted with twin engines providing 534 kN (54,400 kgp / 120,000 lbf) thrust each. The 534 kN engine proved only to be a stepping stone, though it did power the Army's Redstone.
That was a challenging target and required new technology. Earlier rocket engines, such as the V-2's, had featured "regenerative cooling", in which the nozzle was built with an inner and outer shell, with tubing for fuel threaded between the shells. This cooled the engine nozzle and "preheated" the fuel with energy that would otherwise be wasted, resulting in more thrust. This scheme simply wasn't strong enough to be scaled up to a more powerful engine. A Reaction Motors engineer named Ed Neu had come up with an alternative that was scalable: build the nozzle itself out of fuel tubing, brazed together and reinforced with metal bands for strength. Another innovation was a new turbopump design. The turbopumps driving the V-2's engine had been driven by hydrogen peroxide, but Bollay's new engine used a more efficient "gas-generator cycle", driven by hot combustion chamber gases.
Bollay's group finally managed to get their big engine running properly. The initial version burned alcohol and liquid oxygen, as had the V-2, but further work made it even more powerful by fueling it with kerosene and liquid oxygen. This modification was done under what was designated the "Rocket Engine Advancement Program (REAP)", begun in early 1953.
REAP was a tricky business, since the rocket men were very familiar with alcohol, while kerosene was something new and for that reason troublesome. The Air Force's jets used a form of kerosene known as "JP-4", but it turned out to be unacceptable for rocket propulsion. JP-4 varied too much in density, which meant that predicting the weight of a rocket fueled with it would be a problem, and it also turned out to be too impure, clogging the fuel paths. Research led to a new form of kerosene, known as "RP-1", that was very pure and of constant density. The end result of REAP was to improve the performance of the engine to 600 kN (61,200 kgp / 135,000 lbf) of thrust.
* By the mid-1950s, the Aerophysics Laboratory had been spun off into two NAA divisions, one named "Rocketdyne", which worked on rocket engines, and the other named "Autodyne", which built guidance systems. Rocketdyne and its competitor, Aerojet-General, would build the rocket engines that would take Americans into space. The Air Force was already providing funding to Rocketdyne for preliminary studies of a next-generation engine that would have 1,334 to 1,776 kN (136,000 to 181,000 kgp / 300,000 to 400,000 lbf) thrust.
Bollay wasn't in the field by that time. In 1951, after disagreements with the management, he went into business for himself, building battlefield missiles for the US Army, and had little further involvement in the race into space.
BACK_TO_TOP[4.2] PROGRESS IN SOLID FUELS
* While NAA was advancing the state of the art for liquid-fuel rockets, another quiet revolution was taking place on a smaller scale for solid-fuel rockets. JPL's development of the asphalt / potassium perchlorate solid fuel for the Private missile had been a great step over the propellant explosives used for earlier solid rockets, but it was only an initial step, and they continued to refine their solid-fuel mixtures.
The JPL researchers became interested in a class of solvent-resistant synthetic rubber materials known as "thiokols". They began to order quantities of the material from its manufacturer, Thiokol Chemical Corporation, mixing it with an oxidizer, generally ammonium perchlorate, and powdered aluminum to synthesize rocket fuel. Thiokol Chemicals wasn't doing very much business at the time, and the president of the company, Joseph Crosby, got to wondering why one customer was ordering such large quantities of his product. He got in contact with JPL, and on learning about their application, recognized a new business opportunity.
Crosby started to push the company into the rocket fuel business. Further research into synthetic rubber-based solid rocket fuels led to the development of materials that could be poured into rocket shells and cured to form a solid block, without shrinkage or gaps that would interfere with controlled combustion. It was a tricky, exacting process, since the fuel had to be extremely well mixed and the pouring had to be performed in a vacuum to avoid bubbles, but such rockets could be stored for long periods of time, and also could be scaled up to sizes that would be inconceivable for rockets using propellant explosives for fuel.
Thiokol produced a large solid-fuel motor for a variant of the GE Hermes A-2 missile, designated the Hermes RTV-A-10. Three were launched in 1953. These were experimental vehicles, but Thiokol went on to develop a large and powerful solid-fuel rocket engine with 200 kN (20,400 kgp / 45,000 lbf) thrust for the US Army's Sergeant tactical missile, which was first launched in 1956 and replaced the clumsy liquid-fueled Corporal.
BACK_TO_TOP[4.3] ATLAS EMERGES
* While NAA was working on Navaho, the Air Force was taking another look at the intercontinental ballistic missile (ICBM). In December 1950, a RAND study suggested that ICBMs were now technically within reach. Although the USAF remained focused on manned bombers, the service hedged the bet by initiating "paper" design studies for an ICBM with Convair and Charlie Bossart in early 1951. Bossart's original concept for the ICBM, which he named "Atlas" after Convair's parent company, Atlas Corporation, was a monster. It was to be 48.8 meters (160 feet) tall, weigh 304,000 kilograms (670,000 pounds) fully fueled, and powered by seven of the 334 kN engines Bollay was developing for the revised Navaho project. It would carry a 3,630 kilogram (8,000 pound) warhead.
Air Force direction of the study was performed by Lieutenant Colonel Edward N. Hall, working out of Wright-Patterson Air Force Base in Ohio. Funding was on a shoestring, mostly "bootlegged" from money allocated for the Navaho program.
* The original Atlas concept was a lot to bite off, but in 1952 the USAF cut its estimate for the warhead size to 1,360 kilograms (3,000 pounds), reducing demands on the missile's lift capacity. The difficulty of developing an accurate guidance system remained.
The US detonated the first hydrogen fusion bomb, codenamed MIKE, on Eniwetok Atoll in the Pacific on 1 November 1952. This initial device was a proof of concept demonstration, far too big to be a useful weapon, since it was based on liquefied deuterium (heavy hydrogen), which required deep-cryogenic cooling systems. However, American nuclear weapons developers quickly determined that powerful H-bombs could be made much smaller using lithium deuteride, a compound that resembled table salt.
A missile armed with such a powerful fusion warhead would not need to be as accurate as one armed with a less powerful fission warhead. As long as the missile came down in the general area, the fusion warhead would be powerful enough to destroy the target. A technical committee consisting of top-rank physicists and weapons scientists and chaired by the prestigious Hungarian-American mathematician John Von Neumann was formed to help forecast the exact details of yield and size of weapons that would be available as a guide to US nuclear planning, and provided useful guidelines.
The Soviet Union detonated their own hydrogen weapon in August 1953. The Soviet device was not in a league with what the Americans were working on and some Western analysts thought it was a sham, calling it a "fusion-boosted fission bomb" and really nothing new. However, it was a powerful weapon and the Soviets clearly intended to go farther. The Americans were challenged. In September, an Air Force report announced that powerful H-bombs would soon be available that weighed only 680 kilograms (1,500 pounds). That in turn meant a smaller Atlas, weighing no more than 109,000 kilograms (240,000 pounds), about a third of the original weight estimate.
* Such developments made many think that it was time to move forward on Atlas. At the time, the Eisenhower Administration was rethinking American defense policy under an initiative named "New Look". One aspect of New Look was consideration of strategic missiles.
Trevor Gardner, a special assistant to Air Force Secretary Harold Talbott and in charge of research and development issues, formed another blue-ribbon committee designated the "Strategic Missiles Evaluation Group". Once again, it was chaired by John Von Neumann and included the best available talent. Gardner named it the "Teapot Committee". The Teapot Committee began work in the fall of 1953, and released its report in February 1954. Unsurprisingly, the Navaho and Atlas programs were prominent features of their deliberations. Gardner leaned toward Atlas, as did RAND, whose reports influenced the Teapot committee.
At the time, as far as Navaho was concerned, research was in progress on its rocket and ramjet engines, as well as the guidance system. NAA had designed a flight test vehicle named the "X-10" that was powered by conventional turbojet engines as a prototype for the cruise missile component of Navaho, but Navaho itself was a long ways from flight test.
The Teapot report concluded that work on Navaho should continue on track, but relegated Navaho to the status of a backup plan: Atlas was the way of the future. However, the report did not suggest that formal Atlas development begin immediately, instead proposing that another round of studies be performed over the next year that would come up with a detailed plan for Atlas development. That plan would be the basis for an accelerated development program. Although the report praised Convair's work, it also stated the full Atlas development program would probably be well beyond Convair's capability. The report stated that a high-level government organization be established to direct development of Atlas, with the actual development work spread over several firms. The model was the US "Manhattan Project", which had developed the atomic bomb during World War II.
* The Teapot report only made recommendations; nobody on the committee was empowered to commit the US government to anything. Gardner needed to sell it to the president, the National Security Council, and the Joint Chiefs of Staff. Fortunately, they were all in a mood to listen. In mid-1954, President Eisenhower appointed a committee chaired Massachusetts Institute Of Technology's (MIT) James Killian to provide an assessment of America's strategic situation. The committee issued its report in mid-February 1955.
The Killian Report leveraged off intelligence estimates that reported the USSR was developing nuclear weapons, missiles, and strategic bombers at a rate that made it possible for the Soviets to knock out the US in a nuclear strike as early as mid-1954. American leadership assumed that the leadership of the Soviet Union was focused on world domination, and that if the USSR gained an advantage over the US it would be used without hesitation. The first assertion was in hindsight doubtful; given the level of Soviet fear of the West, the second was a much harder call.
New American fusion-bomb tests conducted on Bikini Atoll in the Pacific in 1954 demonstrated that the technology for powerful, lightweight missile warheads was in reach. The Killian Report indicated that ICBM development should be a top priority. That matter was already being taken care of. In May 1954, the decision came down from the top of the US defense hierarchy to begin serious development of the Atlas ICBM as a top-priority project. A USAF project office was in charge of the project and provided direction and oversight, but to coordinate the detail work, Gardner turned to two members of the Teapot committee, Simon Ramo and Dean Wooldridge.
Ramo and Wooldridge had been corporate vice-presidents at Hughes Aircraft, and had led the development of missile guidance systems, as well as advanced fire-control systems for interceptor aircraft. However, Howard Hughes, in charge of Hughes Aircraft, had been in a serious wreck of an experimental aircraft some years before. Always unconventional, chronic pain and drugs seemed to be pushing Hughes off the deep end. Ramo and Wooldridge, tiring of Hughes' erratic management, decided to quit and form their own company, Ramo-Wooldridge. They obtained financial backing from an auto-parts company from Cleveland, Ohio, named Thompson Products, and eventually the company would become Thompson-Ramo-Woolridge (TRW). Ramo-Wooldridge also had the backing of Trevor Gardner, and the company's activities began to ramp up dramatically, bringing in top talent. By 1957, Ramo-Wooldridge would be coordinating the activities of 220 different subcontractors. Development of Atlas required a good proportion of the entire technical resources of the United States.
* Air Force oversight for the effort was led by Brigadier General Bernard Adolph Schriever, a naturalized American of German birth who had been an Army Air Forces bomber pilot in World War II and was legendary for his drive and competence. In mid-1954, he set up his project office, with the bland and unenlightening name of "Western Development Division (WDD)", in Los Angeles, California, not far from the Ramo-Wooldridge office. The Air Force staffers of the WDD went to work in civvies to avoid attracting attention.
Schriever was a decisive leader. A company whose bid for Atlas work had been rejected pressured Air Force Secretary Harold Talbott to be awarded the contract anyway. Talbott arranged a meeting with Schriever, Ramo, and Gardner, and told Schriever to change the contract award. Schriever regarded the company in question as not up to the job and simply refused; Ramo and Gardner backed him up. Talbott threw a tantrum, threatening Schriever: "Before this meeting is over, General, there's going to be one more colonel in the Air Force!"
Schriever replied cooly: "I can't accept that directive, because I have a prior and overriding order." Schriever explained that he was responsible for getting Atlas flying in the least possible time, and asked Talbott if he wanted to write out a new set of orders to rearrange the priorities. That would have upset the political applecart behind Atlas, and Talbott was not willing to ask for that much trouble. He went silent, and then grudgingly gave in to Schriever.
BACK_TO_TOP[4.4] BUILDING ATLAS
* The Atlas design that emerged envisioned a "half-stage" configuration. Building a multistage rocket was a tricky proposition, equivalent to putting one complete rocket on top of another and then launching the second rocket in flight. The Bumper-WAC experiments had proven it could be done, but Bumper-WAC was a long ways from a serious missile. On the other hand, building a missile as a single stage meant that as fuel was consumed, the missile carried around dead weight. Atlas got around this problem by lifting off with three engines, and then discarding two of the engines once the missile reached speed and altitude. All three engines could be ignited at one time on the ground, and discarding the half-stage was a relatively straightforward operation.
There were other problems. One of the biggest, unsurprisingly, was the guidance system. The Teapot report had indicated that the "circular error probability (CEP)" of the Atlas, or radius around the target point where the missile needed to land, would have to be in the range of 3.7 to 5.5 kilometers (2.3 to 3.45 miles). However, if Atlas had a guidance system no more accurate than that used by the V-2, it would have a CEP of 240 kilometers (150 miles). The Atlas guidance system had to be about two orders of magnitude more accurate. Radio guidance updates could be used to provide more accuracy, and in fact radio guidance was used in the first generation of US cruise missiles. The difficulty was that this required having radio stations along the missile's line of flight, and this would be problematic for a strike deep inside Soviet territory. The Atlas had to carry its own guidance.
The problem was tackled by Charles Stark Draper, a professor at the Massachusetts of Technology (MIT). "Inertial" guidance systems, which track changes in velocity to allow an aircraft or missile to determine if it is on course, were based on gyroscopes. Traditionally, the wheels of gyroscopes were relatively heavy and had to be mounted on heavy bearings, and the friction tended to introduce a "drift" error in the gyroscope. During the war, Draper had designed "floating" gyros, which were enclosed in a container full of heavy fluid. The buoyancy reduced the load on the bearings, allowing fine jeweled bearings to be used with correspondingly less drift. To provide the CEP required by the Atlas, Draper had to improve on his floating gyro, heating the fluid to a constant temperature and ensuring that the device was manufactured in a dust-free environment.
The guidance system used gyros to determine changes in velocity, but it also required a computer to calculate if the missile was on course and provide guidance corrections as needed. At the time, digital computers were too big and bulky to be carried on an ICBM, but analog computers could do the job just fine. In an analog computer, the missile's trajectory, acceleration, and other parameters were modeled by electrical waveforms that changed in step with the inputs from guidance sensors, with simple electronic circuits modifying the waveforms to perform calculations. Analog computers were compact, relatively easy to implement, and worked well, though they were basically custom-built to perform one type of calculation and their operation could only be modified to a limited extent.
* Another problem was re-entry of the warhead section of the missile from space back into the atmosphere at a speed of about 25,800 KPH (16,000 MPH). The friction heating of the "reentry vehicle (RV)" built up enough heat to destroy the warhead. While many thought that the solution would be a nose cone that was highly streamlined, like the nose of a jet fighter, in 1953 two aerodynamicists, Julian Allen and Alfred Eggars, showed that the warhead should be blunt, capped by a heat shield that would resist the friction. At such high speeds, the air in front of the heat shield would pile up and shed much of the heat.
Actually testing such ideas was troublesome because of the extreme conditions involved. A Cornell University physicist named Arthur Kantrowitz developed a test chamber called a "shock tube", consisting of a chamber with two sections, separated by a thin metal membrane. One part contained a small nose cone model in a vacuum. The other contained a mixture of oxygen and hydrogen. A spark in the oxygen and hydrogen caused an explosion that burst the diaphragm, sending a shock wave past the nose cone model. The shock wave only lasted for an instant, but high-speed instruments could capture useful data in that time.
The shock tube provided useful aerodynamic data, but still did not duplicate the high temperatures of re-entry. In early experiments, models were placed in the exhaust of a rocket engine, but that didn't prove hot enough. The next step was the "arc tunnel", a supersonic wind tunnel in which the airflow passed through an electric arc of staggering power, providing test temperatures of 7,750 degrees Celsius (14,000 degrees Fahrenheit). Ultimately there was no substitute for flight testing, and Lockheed built a three-stage solid-fuel rocket designated the "X-17" to fly model nose cones. The first stage sent the vehicle to high altitude, while the second and third stages accelerated the model downward to a high velocity.
Early concepts for heat shields envisioned that they would be made of solid copper, but such a heat shield was very heavy. George Sutton, a General Electric physicist, came up with a better idea, the "ablative" heat shield, which was made of a plastic composite. The ablative heat shield material was heat resistant, but it also burned away slowly during re-entry, with the lost mass shedding the heat.
* Schriever kept close track of the subcontractors working on Atlas. His work was complicated by the fact that contracts for most of the critical subsystems were issued to two separate and more or less competing firms. For example, both NAA and Aerojet were working on development of the rocket engines for the Atlas, both General Electric and Avco Everett were working on the nose cone, and so on.
That sounds wasteful, but there was a rationale behind it. Schriever had made a name for himself in the Air Force hierarchy by proposing what he called "concurrent engineering". Traditionally, engineering projects tend to work on one subsystem at a time, eventually integrating them into the final product. This had the advantage of making use of limited resources, as well as permitting incremental testing of subsystems during development, at the cost of a long development cycle. In concurrent engineering, different subsystems were developed in parallel to the maximum extent possible, and then integrated. That permitted a much faster schedule, but it imposed a great deal of management overhead and implied large resources. Duplicate sources for critical subsystems helped reduce the risk that the entire fast schedule could be derailed by development problems with one subsystem.
Concurrent engineering did mean great expense, but Schriever pointed out that delays in any large project were expensive as well, and reducing the risk of delays reduced the final cost of the project. It was also implicitly a scheme by which the US government encouraged the development of new technologies throughout US industry.
BACK_TO_TOP[4.5] TITAN, JUPITER, & THOR
* In 1955, the US took the insurance policy of second-sourcing missile development to a new level by initiating development of a new ICBM, the two-stage "Titan", to be built by the Martin Company, which had built Viking. The Air Force had concluded that building a second ICBM was a logical extension of the policy of duplication that backed up the Atlas program. Under the circumstances, building another missile would increase overall program costs by only about 5%, and would provide insurance in case something went seriously wrong with Atlas. Titan was on the slower development track and was designed in a more robust and sophisticated fashion. Its airframe was built much like that of an aircraft, not the relatively fragile balloon construction of the Atlas, and it was a true two-stage missile. It would also be able to lift a more powerful warhead.
The US was well on its way to developing an ICBM capability. As it would turn out, Atlas and Titan would only be an interim solution for America's nuclear deterrent force, but when the effort to explore space finally reached the ignition point, they would be ready to serve in that role.
* Titan wasn't the end of the story, either. Concerns from intelligence that showed that the Soviets were developing "intermediate range ballistic missiles (IRBMs)" that could hit Britain from mobile launchers in East Germany predictably led the Americans to consider a similar weapon of their own. Among other benefits, an IRBM could be developed quickly and provide an interim nuclear strike capability until ICBMs came along. Von Braun and his people at Huntsville came up with a proposal for an American IRBM named "Jupiter", originally conceived of as basically a bigger and better Redstone, and in March 1955 he wrote a memorandum to Schriever that suggested Redstone Arsenal could develop this weapon for the Air Force.
General Schriever saw such an arrangement as highly unrealistic in organizational terms, given the realities of interservice rivalries, and rejected it immediately. Schriever believed that an IRBM could be derived from the second stage of the Titan, but in July he received a report that indicated such an approach could not provide the necessary range. Schriever bit the bullet and set up a team to propose a "clean-sheet" IRBM design, which was given the name "Thor".
The team consisted of Robert Truax, on loan from the Navy to Schriever's WDD, and Adolph "Dolph" Thiel, one of von Braun's people who had left Redstone Arsenal to work for Ramo-Wooldridge. Truax and Thiel leveraged off the expertise and data built up in Schriever's organization, and by the beginning of September 1955, had a proposal for Schriever. The single-stage Thor was designed to fit into a Douglas C-124 Globemaster cargolift aircraft for airlift, and would use the rocket engine being designed for the Navaho. Schriever immediately sent the design upstairs for approval.
The Atlas program had been ambitious enough, but now the US was trying to develop at least three long-range missiles in parallel, just as if the country was on a "hot war" footing. Obviously, normal peacetime procedures and bureaucracy were not going to work under such conditions. Trevor Gardner had lobbied all through the summer of 1955 to set up a fast-track management scheme for missile development, using the recommendations of the Killian Report as a lever.
Schriever and Gardner went to the new Air Force Secretary, Donald Quarles, and traced through an organization chart to demonstrate just how tangled the chains of responsibilities for missile development really were. Quarles was convinced, and did the logical bureaucratic thing: he set up a committee, under his deputy Hyde Gillette, to figure out how to cut through the rat's nest of existing committees. That sounds a little comical, but the Gillette Committee did its job well. Schriever's WDD was given sole authority for Air Force development of long-range missiles. The committee recommended that a single reviewing authority, the "Ballistic Missiles Committee", be set up in the Air Force hierarchy to provide oversight, with a similar committee set up under the secretary of defense with the ultimate decision-making powers.
That was a great improvement, but politics are a certainty in life, and while the Air Force was ramping up to get Thor development moving as fast as possible, von Braun and the Army were still lobbying for their Jupiter missile. In fact, they had managed to get the US Navy interested in the concept. The Navy wanted an IRBM that could be launched from ships, and in particular submarines, with the desire motivated by interservice rivalry. The Air Force controlled the American nuclear deterrent through LeMay's Strategic Air Command. The Navy could perform nuclear strikes using bombers launched off aircraft carriers and had been developing the Regulus cruise missiles, but the real power lay with SAC.
Admiral Arleigh Burke had taken over as Chief of Naval Operations in August 1955. The Killian Report had suggested that IRBMs be based on naval vessels, and Burke immediately endorsed the idea. Burke was particularly interested in the prospect of carrying IRBMs on the Navy's new atomic submarines. Such submarines would be able to stay at sea for extended periods of time, and launch strikes at the Soviet Union or other strategic enemies from off their shores. They would be difficult to find and destroy, providing the United States with a formidable nuclear deterrent. They would also allow the Navy to become a "strategic nuclear power" to rival SAC. Thor was too tall to fit on a submarine, but von Braun managed to squeeze the Jupiter design down so that it would fit, if just barely.
The issue was hashed out among the US Joint Chiefs of Staff, and on 8 November 1955, Secretary of Defense Charles Wilson, previously president of General Motors, authorized development of both Thor and Jupiter. However, the Army's Jupiter effort labored on as a shoestring operation, while General Schriever, now a bureaucratic demigod, moved forward rapidly on Thor, along with Atlas and Titan.
Schriever put Thor out for bid, with Douglas Aircraft, Bell Labs, Lockheed, and North American submitting proposals. They were given one week to prepare. Douglas, the favored candidate from the beginning, won the competition in December 1955. Douglas would be provided engines, guidance systems, and nose cones developed by the network of other contractors working for WDD, and would integrate them into an operational IRBM. The project was on the fast track.
The engine that would power all these missiles, except for the Titan, was now under intense development by North American's Rocketdyne subsidiary. The design team performed test firings at the Santa Susanna site and, as development progressed, at Edwards Air Force base, up the California coast. Aerojet was conducting work along a somewhat slower track for the Titan engine.
Since the new missiles had clearly outgrown the White Sands test range, launch facilities were being built up at Cape Canaveral on the east coast of Florida. "The Cape", as it would become known, had been selected as a missile test center in 1947, since it had a big open downrange flight path southeast over the Atlantic. The British agreed to let the US to build tracking stations in the Bahamas to help monitor test flights, and the first launches from the Cape, the last two Bumper-WAC flights, took place in June and July 1950. The Cape had been used primarily for Snark test flights since then. Now it was being built up rapidly.
Everyone was in a hurry. The Thor design was finalized in July 1956, and the first Thor, number 101, was flown to the Cape by C-124 transport in October, followed by the second, number 102, in November.
BACK_TO_TOP[4.6] POLARIS
* That November Defense Secretary Wilson, in an attempt to cool the interservice rivalries that were interfering with missile development, dictated that the Army could not deploy a missile with a range of more than 320 kilometers (200 miles). Jupiter's range was 2,415 kilometers (1,500 miles), and though the Army could develop it, the Air Force would have to deploy it. The Air Force was clearly not enthusiastic about this idea.
The Navy had also backed away from the Jupiter by this time. Admiral Arleigh Burke had assigned responsibility for Navy IRBM development to a new "Special Projects Office (SPO)" under Rear Admiral William Raborn, with clout comparable to that enjoyed by the WDD and General Schriever. The Jupiter was not exactly what the Navy wanted. They had only considered it because they were not sure they could get anything better, and at least wanted to keep a "foot in the door" of the nuclear deterrence game. Jupiter was still on the big side, and more to the point handling a liquid-fuel missile on a naval vessel was both troublesome and dangerous. The Navy had conducted an experiment named "Operation Pushover" at White Sands after the war, where a V-2 was deliberately destroyed on a "simulated carrier" built in the desert, and the damage to the "vessel" had been extensive.
Solid fuels had continued to advance since 1950, and in 1954 the Navy awarded a contract to Atlantic Research, located in the state of Virginia, to perform advanced studies in the field. Two Atlantic Research scientists, Keith Rumbel and Charles Henderson, conducted a series of tests on solid fuels featuring a very high proportion of aluminum powder. Up to this time, a 5% aluminum mixture was regarded as optimum since it was believed thrust would fall off above that level. However, Rumbel and Henderson hadn't heard about this "law" and tried higher proportions, to find significant improvements. By early 1956, their new fuel mixtures were demonstrating levels of thrust competitive with liquid-fuel rockets.
The Navy really wanted a solid-fuel IRBM for launch from submarines, but the results of SPO's initial studies were discouraging, envisioning a missile so big that a huge submarine would be required, and would still only carry four missiles. The major problem was that as specified at the time, the missile would have to carry the Jupiter nose cone and weapon, and that weighed 1,360 kilograms (3,000 pounds).
Fortunately for the Navy, in the summer of 1956 weapons designer Edward Teller was promoting a new idea. Teller was as brilliant as he was enthusiastic in building clever new bombs, and he proposed making much more generous use of enriched uranium than had been the custom to create a lightweight fusion warhead. With Teller's new bomb technology, the size of an IRBM nose cone could be reduced to a mere 385 kilograms (850 pounds), and still be an order of magnitude more powerful than the weapon that destroyed Hiroshima. Using Teller's projected lightweight warhead, the SPO was able to define a solid-fuel IRBM with a range of 2,200 kilometers (1,340 miles) that only weighed 13,100 kilograms (28,800 pounds), about the same as a V-2 on the launchpad, and was only 9.15 meters (30 feet) tall. The missile was named "Polaris", after the North Star. It would be America's first "submarine launched ballistic missile (SLBM)".
To build a submarine that could carry the carry the Polaris, the SPO decided that they could take an existing SKIPJACK-class nuclear attack submarine, cut it in half behind the conning tower, and splice in an extension with two rows of silos housing a total of 16 missiles. Raborn pitched the Polaris to Defense Secretary Wilson, who proved enthusiastic about the capabilities and particularly the relatively low cost of the design. On 8 December 1956, Wilson issued an order allowing the Navy to pull out of the Jupiter program and move full steam ahead on Polaris.
* Wilson did not cancel Jupiter, since it was useful as a backup if the fast-track Thor program faltered, and it was worthwhile in any case to give the ingenious von Braun and his crew something to allow them to sharpen their skills. By this time, von Braun's group had become separate Army organization, the "Army Ballistic Missile Agency (ABMA)", with the mild joke that "ABMA" could just as well stand for "Alabama". ABMA had been split off from the rest of the Redstone Arsenal organization in 1956 and placed under the command of Brigadier General John B. Medaris; Holger Toftoy retained command of development of smaller missiles at the site under the "Army Rocket & Guided Missiles Agency".
In the meantime, the name of Schriever's Western Development Division had been changed to the less evasive "Ballistic Missile Division (BMD)". BMD was working on Atlas, Titan, and Thor, and the idea that such a massive effort could be kept a complete secret was ridiculous.
BACK_TO_TOP[4.7] TRIAL AND ERROR
* Von Braun continued his work and performed test flights from the Cape of Jupiter systems on board Redstones. One Redstone went haywire after launch and fell towards the Thor launch site. The range safety officer blew it up and it crashed into an empty field. Von Braun's boss, General Medaris, said later: "We were accused of having a very inaccurate missile since we had found it impossible, even at that short range, to hit the Thor launch pad."
The Thor launch pad survived such "attacks", and on 25 January 1957 Thor 101 was on the pad, ready to take off. The countdown went to zero, the engines ignited, the missile tried to rise off the pad, and then it fell back, broke in half, and blew up in a tremendous explosion.
The failure of the first attempt to launch an American long-range missile was disappointing, but not all that surprising. Nearly all other missile development projects had gone through a painful learning curve and it was simply too much to hope that Thor would be different. The problem was traced down by examining the wreckage and watching films taken of prelaunch procedures. Someone spotted one of the launch crew dragging a liquid oxygen fuel hose in the sand, and the conclusion was that a small amount of sand had contaminated the liquid oxygen supply. Fueling procedures were tightened up.
In the meantime, von Braun and his team were preparing to launch their first Jupiter. It lifted off on 1 March and flew for 74 seconds before going up in a fireball. High temperatures from the rocket exhaust had set off the explosion, and the Army team quickly designed a flame shield for the base of the missile.
Thor 102 took its turn in April, and flew flawlessly for 30 seconds. However, the range safety officer, apparently misled due to crossed wiring in his console, thought the missile was headed for the city of Orlando and blew it up. The unfortunate range safety officer was quickly sent elsewhere while the team worked overtime to get the next launch ready.
Late in April, the Army team launched their second Jupiter. It flew for 90 seconds, and then went out of control and had to be destroyed. The problem was traced to sloshing of propellants in their tanks. The team rolled wire mesh into cylinders they called "beer cans", put a float on top of each beer can, and put a large number of them in each tank to damp the sloshing.
In mid-May, the Air Force team tried to launch Thor 103, with General Schriever in attendance, but it exploded on the pad five minutes before launch. The problem was traced to a defective fuel valve.
It was the Army's turn again in late May. This time the Jupiter made it all the way downrange, a total distance of 2,397 (1,489 miles). The underdog von Braun team had performed America's first successful test flight of a long-range missile.
The first Atlas test was performed on 11 June 1957. It actually made it off the pad, but lost an engine after takeoff, went out of control, and had to be destroyed. In August, the Army team launched their fourth Jupiter, which proved to be a highly successful flight. The Army was scoring 2:0 against the Air Force, but the Air Force team responded with a successful launch on 20 September 1957, with the Thor flying 2,012 kilometers (1,250 miles) downrange.
Although the launch failures were frustrating, American missile development seemed to be moving along as well as might be expected. However, the American public and Congress had little understanding of industrial and in particular aerospace development projects. After all, if people put up airplanes that crashed and buildings that collapsed more often than not, something was obviously seriously wrong. The fact that technologies in common use had usually gone through a rough learning curve of one sort or another in their early days was not obvious to people who took them for granted.
* While von Braun was launching his rockets, he was enjoying the counsel and friendship of his old mentor, Hermann Oberth. Von Braun had arranged a consulting job for Oberth at ABMA in 1956; Oberth would remain there for four years, but von Braun was unable to get a long-term position for him there, and he returned to Germany. Oberth would live into his nineties, finally dying in 1989 after observing much of what he had prophesied come true.
BACK_TO_TOP
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