UGM-27 Polaris

• 1. Introduction

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  The UGM-27 Polaris arrived at a moment when naval officers were still arguing about whether a submarine could reliably launch a ballistic missile at all. In the summer of 1956, at a remote point on the Massachusetts coast called Nobska, a nuclear physicist named Edward Teller made a promise that most of his colleagues considered reckless. He said he could deliver a one-megaton hydrogen bomb warhead small enough to fit inside a new, untested missile. Nobody had done it. His rival from Los Alamos, J. Carson Mark, called him wrong. What followed was a crash program that, in less than four years, put the United States Navy into the nuclear deterrence business permanently. Polaris would serve from 1961 to 1980. It would reshape the relationship between the American and British militaries, trigger a new round of infighting between the Navy and the Air Force, and leave behind project management tools that engineers still use today. The questions worth asking are: how did a single bold promise at a summer conference change the shape of nuclear strategy, what did it actually take to fire a missile from a moving submarine, and why did Britain stake its entire nuclear future on an American weapon?

• 2. Teller's Gamble at Nobska

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  Project Nobska was a study sponsored by the Navy and held in the summer of 1956 at Nobska Point in Woods Hole, Massachusetts, under the auspices of the National Academy of Sciences. The question the Navy needed answered was whether a lightweight missile could be built to cover a range up to fifteen hundred miles. At the time, no warhead existed that was both small enough to fit such a missile and powerful enough to matter.

  Edward Teller arrived from the recently formed Livermore nuclear weapons laboratory with a startling answer. He offered to develop a lightweight warhead of one-megaton strength within five years. His competitor, J. Carson Mark, headed the theoretical division at Los Alamos, a job that had originally been offered to Teller. Mark was a cautious physicist. He said half a megaton was more realistic, quoted a higher price, and asked for more time. In the Navy's eyes, that response essentially confirmed Teller's credibility. Whether the warhead was half or one megaton mattered less than whether it would fit the missile and be ready on schedule.

  When Teller returned to Livermore, his colleagues were stunned. He defended the promise by pointing to the trend in warhead technology: each new generation showed reduced weight-to-yield ratios. When challenged about projecting that trend forward, he asked, "Why use a 1958 warhead in a 1965 weapon system?" Almost four decades later, Teller recalled Mark's performance at Nobska, saying it was "an occasion when I was happy about the other person being bashful." When the Atomic Energy Commission backed up Teller's estimate in early September, Admiral Arleigh Burke and the Navy Secretariat moved to commit fully to the new missile, which Admiral Raborn named Polaris.

• 3. The Problem of the Moving Platform

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  Firing a ballistic missile from a fixed land silo is a problem of targeting. Firing one from a submerged submarine moving through an ocean is a problem of knowing where you are in the first place. Polaris developers confronted this from the start.

  The existing Ships Inertial Navigation System, known as SINS, had been created at the MIT Instrumentation Laboratory and supplied to the Navy in 1954. Its "Stable Platform" configuration did not account for changes in gravitational fields as the submarine moved, nor for the continuously shifting position of the Earth beneath it. A missile system is of no use if operators cannot reliably direct it.

  Developers turned to a guidance system the US Air Force had abandoned: the XN6 Autonavigator, developed by the Autonetics Division of North American Aviation for the Navaho cruise missile program. By 1958 it had proved adaptable for submarines. That same year, two physicists at Johns Hopkins's Applied Physics Laboratory, William Guier and George Weiffenbach, began work on a satellite navigation system called Transit, later known as NAVSAT, specifically because submarines needed to know their precise position at the moment of launch. Transit was not operational until 1964, making the first years of Polaris entirely dependent on other position-fixing methods such as LORAN.

  A computer small enough to pass through a submarine hatch, designated the AN/UYK-1, was developed in 1958 to interpret Transit satellite data and send guidance information to the missile itself. Each Polaris carried its own guidance computer built with what the source describes as ultra-miniaturized electronics. By 1962, each guidance chip cost $50. By 1968, the price had dropped to $2.

• 4. Testing, Failure, and the First Shot

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  The first Polaris test flight, designated AX-1, launched from Cape Canaveral on the 24th of September 1958 and had to be destroyed when the missile failed to turn into the correct trajectory due to a programming error. The second test, AX-2, exploded on the launch pad in October 1958. AX-3 on the 30th of December 1958 launched correctly but was destroyed when fuel overheated. The fourth and fifth tests, in January and February 1959, both had to be terminated after erratic behavior in flight.

  The sixth flight, AX-6 on the 20th of April 1959, was the first genuine success. The missile launched, the two stages separated, and it splashed into the Atlantic Ocean some 300 miles offshore. Between these tests, engineers developed and implemented the inertial guidance system.

  The Polaris A-1 that eventually entered service had a range of 1,400 nautical miles and carried a single W-47-Y1 warhead of 600 kilotons. The missile was 28.5 feet long with a body diameter of 54 inches and a launch weight of 28,800 pounds. The two stages were steered by thrust vectoring, and inertial navigation guided it to a circular error probable of approximately 900 meters, making it most suitable against dispersed surface targets like airfields and radar installations rather than hardened underground sites.

  On the 20th of July 1960, the first US missile submarine successfully launched the first Polaris from a submerged position. On the 6th of May 1962, during Operation Dominic, a Polaris A-2 fitted with a live W47 warhead was launched in the central Pacific Ocean in a test called Frigate Bird. That test remains the only American live-fire test of a strategic nuclear missile.

• 5. The British Polaris Program

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  Conversations between American and British naval leadership about Polaris began as early as 1957, when Chief of Naval Operations Arleigh Burke and First Sea Lord Louis Mountbatten started corresponding on the subject. The actual commitment came after a series of British missile cancellations made the situation urgent. After the scrapping of the Blue Streak and Skybolt programs, Prime Minister Harold Macmillan met President John F. Kennedy and the resulting Nassau Agreement, signed in 1962, committed the United States to supplying Britain with Polaris missiles, launch tubes, re-entry bodies, and fire-control systems. Britain would design and build its own warheads.

  The Polaris Sales Agreement was signed on the 6th of April 1963. The deal's language was deliberately ambiguous. For the United States, the wording placed the sale within NATO's deterrence framework. For Britain, the same wording allowed Polaris to be read as a solely national deterrent. Britain initially proposed five ballistic missile submarines; the incoming Labour government of Harold Wilson reduced that number to four, each carrying 16 missiles.

  Polaris became the largest project in the Royal Navy's peacetime history. When the new Labour government considered cancelling it in 1964, the calculation that kept it alive was stark: Polaris gave Britain a global nuclear capacity at a cost roughly 150 million pounds less than maintaining the V bomber force. On the 15th of February 1968, the lead ship of her class became the first British vessel to fire a Polaris. All Royal Navy Polaris submarines operated from Faslane, a few miles from the American base at Holy Loch.

  Control over Polaris targeting was formally assigned to SACEUR, the Supreme Allied Commander, Europe, with a carve-out allowing British authorities to act independently in a national emergency without NATO support. Operational control of the submarines themselves was assigned to SACLANT, based near Norfolk, Virginia, though that authority was routinely delegated to COMEASTLANT, who was always a British admiral.

• 6. Chevaline and the Moscow Problem

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  The original Polaris design was never built to defeat an anti-ballistic missile screen, and the Soviet Union had erected exactly such a screen around Moscow. Britain's problem was specific: its small Polaris force often had only one submarine on deterrent patrol at any given time, and that single boat had to be able to guarantee it could penetrate Soviet ABM defenses alone.

  Britain first examined an American program called Antelope, which assessed various ways to improve Polaris's ability to get through ABM defenses. The assessments were conducted at Aldermaston. Though Britain drew on the Antelope evaluation, the United States provided no design input for what Britain then built on its own. The result was a British program called Chevaline, which added multiple decoys, chaff, and other defensive countermeasures to the Polaris re-entry system.

  Chevaline's existence was kept secret until 1980, and part of the reason it became public was the cost. The project's final price had almost quadrupled the original estimate given when it was formally approved in January 1975. The political fight over Chevaline ran through the Labour Party. The party's Chief Scientific Adviser, Solly Zuckerman, argued that Britain no longer needed new nuclear weapon designs. Secretary of State for Defence Denis Healey was among those who backed the modification. Despite approval, cost overruns pushed the program out: Britain disbanding it as a dedicated project in 1977. The system became operational in mid-1982, and the last British SSBN received it in mid-1987. Chevaline was withdrawn from service in 1996, replaced eventually by the Trident D5 missile, which Britain chose partly to ensure commonality with the US Navy at the shared base at Naval Submarine Base Kings Bay.

• 7. Management Tools Born from Complexity

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  The Polaris program's sheer scale forced the creation of new ways to manage large engineering projects. Managing thousands of contractors and suppliers building components that all had to work together in a weapon that had to fire reliably from a moving submarine required more than the existing Gantt chart approach could offer.

  The Program Evaluation and Review Technique, known as PERT, was developed specifically for the Polaris program as a replacement for the simpler Gantt chart methodology. PERT gave program managers a way to map dependencies between tasks and identify the critical path that determined the project's minimum possible completion time. Polaris was the program that proved the technique at scale.

  The guidance electronics further reflected the program's role as a driver of miniaturization. By 1965, microchips similar to units Texas Instruments produced for the Minuteman II were being purchased by the Navy for the Polaris. Each Minuteman guidance system required around 2,000 of these chips, suggesting the Polaris system used a comparable number. To keep costs under control, the chip design was standardized and shared between Westinghouse Electric Company and RCA. The price fell from $50 per chip in 1962 to $2 in 1968, a collapse in cost per unit that reflected the broader dynamic of military procurement driving down the price of components that would later become commercially ubiquitous. The Strategic Target System, or STARS, used surplus Polaris boosters from 1993 onward, eventually becoming the standard launch vehicle for Ground-Based Interceptor trials from 2004 onward, extending the missile's useful life well beyond its service retirement.