History of Naval Reactors
The Naval Reactors Program was established in 1948 to develop nuclear propulsion plants for the Navy's submarines and surface ships. Since then, the program has been responsible for designing, building, and maintaining the nuclear reactors that power the Navy's fleet. Today, the Naval Reactors Program is recognized as a world leader in nuclear technology and safety.
BEFORE THE BEGINNING
The theoretical possibility of nuclear propulsion was first developed when nuclear fission was discovered in the late 1930's. In March 1939, Enrico Fermi, co-researcher on the first U.S. nuclear fission experiments at Columbia University, held a high-level Department of Defense lecture concerning the potential that nuclear fission held as an inexhaustible source of energy. In attendance was, Dr. Ross Gunn, a physicist and technical advisor to the director of the U.S. Naval Research Laboratory (NRL). NRL had been researching alternative sources of power for the Navy and Gunn quickly realized that nuclear power may be a potential answer to the Navy's submarine propulsion woes. At the time, concurrent research was investigating the use of fuel cells, hydrogen peroxide-alcohol steam turbine, and closed cycle diesel engines, however, each of these methods continued to offer no improvement to submarine stealthiness or crew safety as the need to surface, even if partially, maintained the vulnerability of the submarine.
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Shortly after the Fermi lecture, Gunn and NRL director, Captain Hollis Cooley successfully pleaded the potential benefits of this technology to Admiral Harold Bowen, Chief of the Bureau of Engineering. This effort resulted in an initial investment of approximately $1,500. Working with these modest funds, Gunn and his colleagues immediately began to explore methods of uranium enrichment as a source of U-235 which would be essential to accomplish any reactor experiments. However, NRL found that candidate methods to enrich U-235 all proved to be extremely dangerous, expensive and time consuming.
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In the summer of 1940, the Navy provided $100,000 to fund innovative U-235 isotope separation research at several universities. One of the pivotal results of this effort was by Dr. Phillip Abelson at the Carnegie Institute of Washington who was developing a promising liquid thermal diffusion isotope separation technique. Gunn saw the potential for this enrichment technique and managed to get Abelson to join NRL in June 1941 to help with the Navy efforts — Note that this was six months prior to the Japanese attack at Pearl Harbor. Abelson's process required significant amounts of steam and full-scale diffusion facility was built at Philadelphia Navy Yard (where large-scale sources of high-pressure steam could be made available at the Naval Boiler and Turbine Laboratory) to support the Navy's research needs for U-235. These efforts were completely independent of the Army's Manhattan Project who consciously excluded the Navy but were also struggling with the same gaseous diffusion processes that Gunn had rejected. In 1943, Oppenheimer learned of the Navy's work and the Navy was funded to expand Philadelphia capabilities. In 1944, the Philadelphia effort was provien to be a success and the S-50 plant in Oak Ridge was built using the Navy's process. This would be an important turning point for nuclear submarine efforts as it gave Navy scientists access to the Army's Manhattan Project reactor knowledge.
For the duration of World War II, Navy efforts were diverted from the Navy uranium efforts to more urgent work on completing the atomic bomb. However, Navy interest in using nuclear energy for ship propulsion remained and in early 1946 Philip Abelson spent several months at Oak Ridge Laboratory (as the Navy's only representative on power work) studying nuclear reactor design. Blueprints of a German Type XXVI Walter submarine, considered the most advanced design of the time, were obtained by NRL and work began on how to retrofit the diesel and battery power system with an atomic reactor. The initial concept was to take thermal energy generated in the atomic 'pile' and to transfer it to liquid sodium-potassium (KNa) alloy recirculated through the pile. This heat would drive a steam turbine. The pile, together with its shielding and the KNa heat exchanger, would be located outside the pressure hull along the keel of the submarine. This arrangement would allow for convenient maintenance and replacement in drydock.
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With this concept, Abelson wrote the first ever report detailing how a nuclear reactor could be installed in a submarine. While not written at an engineering-design level, it provided concepts for both propulsion and electrical power. The results were compiled and circulated in a report entitled Atomic Energy Submarine dated March 28, 1946, and followed by briefings with naval officials and the submarine community. The report provided the following recommendations:
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Navy obtain authority and support tor establishment of a high priority project with a special "task force" sufficiently informed on all phase of the problem to supervise and coordinate the all project or research, development. construction. and testing or an atomic-powered submarine.
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Request the Manhattan District to give high priority to an energy program adapted to the submarine needs with participation of a team including half a dozen highly competent Naval scientists and engineers.
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Request a Presidential directive to permit mutual cooperation between the scientists of the Manhattan District and the Navy as needed to develop and operate atomic power plant tor Naval use.
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Authorize the design and construction of a submarine hull and machinery suitable tor the exploitation of atomic power in accordance the requirements of the research group responsible tor this project.
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Provide facilities and competent men to permit:
(1) Development of an atomic pile with heat exchange systems with all controls needed for Naval use.
(2) Construct a suitable submarine as above.
(3) Carry out research projects as necessary, including work on heat-exchange media, salt water evaporators.
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Abelson sold the concept to the National Defense Research Committee on the idea of the practicality of nuclear powered submarines during a visit to NRL. This led to a meeting with NRL director Rear Adm. Alexander H. Van Keuren - and the start of a focused effort to convince the Navy to develop the engineering aspects of fitting submarines with a nuclear power plant.
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During briefings, Abelson would line the walls with blueprints, equations and other diagrams, and would vigorously present the importance of extended submerged operations and the need for nuclear power. In attendance at one such briefing, Vice Adm. Charles Lockwood, a veteran World War II submarine commander, who likened what he heard to something out of Jules Verne's Twenty Thousand Leagues Under the Sea, an analogy that may have inadvertently inspired the naming of the first nuclear submarine
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In June 1946, the Chief of Naval Operations, Fleet Adm. Chester W. Nimitz decided to send five officers (including then Captain Hyman Rickover) and three civilians to Monsanto Chemical Company - Clinton Laboratories (renamed Clinton National Laboratory in 1947 and then Oak Ridge National Laboratory in 1948) in Oak Ridge, Tennessee, to study the potential of using nuclear energy to power ships. Before going to Oak Ridge, Rickover spent time in Washington studying all of the available information on the possible use of atomic energy for naval propulsion. He also talked to everyone who had anything to offer. At Oak Ridge, he and the other naval officers had offices in the same small building with the Daniels Pile group. Under the leadership of Dr. Farrington Daniels, the Pile group's objective was the construction of a power generating reactor plant using a high-temperature, gas-cooled, beryllium-moderated reactor which could ultimately generate central station electricity. While they did not take part in the actual development and design effort., Rickover and the Navy team did monitoring and provided assistance while studying every aspect of the work at Oak Ridge to determine its potential applicability to naval propulsion. In addition, they later visited the other facilities under the Manhattan District.
The Navy group organized themselves under Captain Rickover (or better described as Rickover organized them) and embraced Abelson's concept of a nuclear-powered submarine. The consensus of the group was that the technical difficulties could be overcome, and nuclear power could be used as a means for propelling Navy ships.
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Meanwhile in Washington DC in mid-1946, a submarine desk was established in the office of the Assistant Chief of Naval Operations (CNO) for Atomic Defense. The first officer assigned was Lt. Commander Edward L. Beach, who became a naval aid to President Eisenhower, and later CO of the nuclear submarine USS Triton.
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In August 1946, the Atomic Energy Act of 1946 was signed into law, enabling closer cooperation between the Navy and a new Atomic Energy Commission (AEC) starting on January 1, 1947. The Atomic Energy Commission was assigned responsibilities for nuclear reactor plant development. Later that month, Chief of Naval Operations, Fleet Adm. Chester W. Nimitz, approved a program for the design and development of nuclear power plants in submarines. This was the Navy’s first authoritative statement of an operational requirement for nuclear power in submarines.
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Back in Oak Ridge in 1947, the Daniels Pile group efforts were terminated due to AEC prioritization on nuclear weapons. While the Pile Group was working on their final report, Rickover unofficially persuaded them to use their experience to do a conceptual design of a gas-cooled ceramics reactor pile for submarine use (Report B-137 File CL-FD-55 dated 12-10-1947 "Adaptation of High Temperature Gas-Cooled Ceramics Pile to Submarine Use - NR-HA is awaiting reprint permission) and later a conceptual design for a propulsion plant for a water-cooled reactor (Report B-137 File 48-2-43 dated 2-2-1948 "Proposed Water Cooled Power Pile for the Navy" NR-HA is awaiting reprint permission).
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In September 1947, Rickover returned from Oak Ridge to BuShips Washington D.C., which at the time was struggling to define its role with respect to the AEC in developing a nuclear submarine. Vice Admiral Mills, then Chief of BuShips, appointed Rickover as Special Assistant to the Chief, with the task of obtaining high-level Navy and DoD authorization for the construction and installation of an atomic propulsion plant in a submarine.
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As an interesting twist, on December 31, 1947, the AEC decided to centralize all reactor development at Argonne National Laboratory, setting up a long-running battle with the Navy to determine roles and leadership of of the emerging naval reactor program. (This would gradually get undone such that by early-1952, essentially all of Argonne's naval reactor responsibilities were transferred to Westinghouse.)
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It is important to recognize that as of 1947, there was only limited experience with nuclear reactors. The United States had three reactors for producing nuclear material for atomic weapons, and five small research reactors. There was no readily available knowledge on operating a reactor that would produce power in a usable form. Developing a power reactor would require new corrosion resistant metals which could sustain prolonged periods of intense radiation, thick shielding to protect personnel from radiation, and new components which would operate safely and reliably. For example, to get information on coolants in July 1947, BuShips would fund a General Electric effort (Project Genie) to study liquid metal (sodium) heat transfer systems and a similar study (Project Wizard) with Westinghouse for pressurized water in June 1948.
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Challenges would be even more difficult for submarine application since the reactor and its associated steam plant had to fit within the confines of the comparatively small hull, and be able to withstand extreme battle shock incident to the operation of combatant ships. The propulsion plant had to be operated and maintained at sea by Naval officers and enlisted men who, although specially trained, were not physicists or scientists. Although application of nuclear power to submarines was a major challenge, it was generally recognized that success would transform submarine warfare. Submerged operation of submarines of the World War II era was limited by battery power and was measured in hours to a few days. Because nuclear fission produced heat without consuming oxygen, a true submarine was possible, one which could remain submerged and steam at sustained high speed for long periods.
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On August 4th, 1948, the Vice Admiral Mills (Chief BuShips) established the Naval Reactors Branch (Code 390) and in February 1949, Captain Rickover became the head of the Naval Reactors Branch of the Atomic Energy Commission. This was the beginning of the joint effort between the Navy and the Commission, an arrangement which continued after the Commission was replaced by the Energy Research and Development Administration and subsequently the Department of Energy.
DEVELOPING THE EARLY TECHNOLOGY
Using information about nuclear reactors from efforts during World War II and the work at Oak Ridge, three reactor approaches were initially considered by Naval Reactors for naval nuclear propulsion. By the summer of 1950, a gas-cooled reactor was shown to not be suitable for naval ship propulsion. However, a liquid metal cooled reactor (Mark A) and a pressurized water reactor (Mark I) approach were both found promising for development and carried through to full-scale prototype plants, and thereafter to shipboard application. Water coolant had significant advantages in that it has good heat transfer properties, is not hazardous or aggressively corrosive, and does not have violent chemical reactions with air. Water does not have any significant long-lived radioactive states, so after-shutdown radiation levels are low and personnel can safely and rapidly enter the reactor compartment to do maintenance within minutes after the reactor is shut down. As a result, a pressurized water reactor was selected for the first submarine NAUTILUS and a liquid metal reactor was selected used for the second submarine SEAWOLF. (2)
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Congress authorized funds for the Atomic Energy Commission to proceed in 1950 with construction of the land prototype of the NAUTILUS propulsion plant. Three years later, the prototype began operation. For the first time, a reactor produced energy in significant quantities and with the reliability needed to drive power machinery. The propulsion plant that was later installed in the submarine NAUTILUS was the same design as the one in the prototype.
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Of the many technical problems encountered in developing the pressurized water concept, one of the most difficult was finding a metal to clad the uranium fuel - one which would not corrode excessively in the presence of high coolant temperatures, would not absorb neutrons needed to maintain a chain reaction, and would not lose its structural integrity under prolonged exposure to intense radiation. Zirconium looked promising but was expensive and available only in small quantities at the time. The Naval Nuclear Propulsion Program proceeded to develop the necessary manufacturing technology to produce large quantities of zirconium alloys at reasonable prices. Zirconium alloys have since been widely adopted in the civilian power industry both here and abroad.
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Another challenge was the unique design criteria applicable to US Navy submarines. The reactor needed to have ruggedness, endurance, maneuverability, and compactness that are far greater than land-based reactors. These requirements directly drove the unique design requirements of naval fuel systems, and are important to ensuring the ability to effectively carry out missions while ensuring safety to the crew, the public, and the environment. (2) Some of the unique criteria to accomplish this were:
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Naval fuels needed to satisfy very high standards for fuel integrity and reliably retain the fission products under extremes of operating conditions, providing maximum flexibility to the propulsion plant to respond to possible casualties and still maintain electrical and propulsion power for the ship.
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Naval fuel elements and modules needed to be rigid and tough, able to withstand the extreme shock loads that might occur in a collision or an attack without losing integrity or compromising the ability to operate the reactor. The design shock loads for naval fuel were more than 10 times greater than seismic loading that would later exist for land-based reactors.
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To minimize the exposure of the crew to radiation, highly radioactive fission products needed to be prevented from getting into the coolant. To accomplish this, the fuel naval fuel element design, materials, and fabrication techniques retain the fission product radioactivity inside the fuel element and prevent radioactivity from reaching the coolant.
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Radioactive shielding would be required so that a typical nuclear powered warship crew member would receive significantly less radiation exposure than a person would receive from background radiation at home in the US in the same period. This conservative engineering and operational approach was viewed as vital to maintaining national and international acceptance, as nuclear-powered warships would make calls into sea ports throughout the world.
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Naval reactors needed to support rapid and frequent power changes to accommodate tactical ship maneuvering without excessive thermally-induced stresses on the fuel system.
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Naval reactor plants on submarines needed to be quiet. As flow-induced noise increases with flow rate and pump input power, Naval fuel systems needed to allow high reactor power for relatively low flow rate and main coolant pumping power to reduce detectability.
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Naval cores needed to be able to operate for years without refueling to minimize life-cycle costs, demand
on support infrastructure, and occupational radiation exposure, while maximizing ship operational availability to Fleet commanders. -
To be cost-effective, naval reactor plants needed to be compact. The reactor needed to fit within the space and weight constraints of a submarine but must still be powerful enough to drive the ship at tactical speeds for engagement or rapid transit to an operating area while carrying sufficient fuel to last for decades
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For the pressurized water reactor, the use of highly-enriched uranium was selected as it maximized the amount of fissile material in the small volume of the core, enabling the longest possible lifetimes while maintaining compactness. (2)
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For the SEAWOLF liquid metal reactor, even more difficult problems presented themselves. Although the SEAWOLF operated successfully for two years, leaks in the steam generators and the potentially dangerous consequences of sodium should it mix with water in a confined submarine were serious drawbacks. Because of these problems and other technical considerations, the liquid metal reactor approach was discontinued for naval application and the reactor plant in the SEAWOLF was replaced with a pressurized water reactor in 1960. (2)
Because of the advantages of virtually unlimited propulsion endurance, the program also pursued development of pressurized water nuclear propulsion plants for surface warships. Congress authorized the world's first nuclear powered surface warship, the USS LONG BEACH, in the fiscal year 1957 shipbuilding program. The ship completed sea trials in July 1961 and joined the fleet in September of that year. In 1956 a nuclear propulsion prototype was begun for an aircraft carrier. The prototype first operated at full power in September 1959. One year earlier the keel for the aircraft carrier ENTERPRISE was laid and she was commissioned in November 1961. During next 51-years, ENTERPRISE sailed over 1,000,000 nm and had over 400,000 aircraft landings.
Learn more about the Enterprise & Its Core
CIVILIAN NUCLEAR POWER PLANT DEVELOPMENT (4)
In the early 1950's, President Eisenhower decided that the United States should be the first nation to have a full scale atomic power plant designed solely for the purpose of producing electrical power. Because of the successful use of the pressurized water concept in naval applications. the Atomic Energy Commission assigned the project to the Naval Nuclear Propulsion Program and Congress provided the funds. The Shippingport Atomic Power Station was built, and reached full power on December 28, 1957, meeting the objective set for it.
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The Shippingport plant pioneered the use of uranium dioxide fuel; use of this fuel system and the development of zirconium alloys represent two of the major achievements of the program which are now in widespread use in the civilian power industry. The Shippingport program also developed the basic technology for reactor plant components, refueling concepts, analytical tools and standards which were later applied to commercial power reactors here and abroad. The first core (1957-1963) used at Shippingport was a seed-and-blanket core that used a large amount of unenriched uranium. The second core (1965-1974) enhanced the basic design for greater power density (2x) and lifetime (5x).
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The Shippingport reactor plant continued in operation with a thorium/uranium-233 fueled core to demonstrate the feasibility of breeding in a light water reactor. Breeding is a process in which the reactor produces more fissionable fuel than is consumed in producing power. Successful development of the technology for breeding, being demonstrated by operation of the
Shippingport Light Water Breeder Reactor core, will make this nation's substantial thorium reserves available for production of electrical power. This represents a potential energy resource greater than the known U.S. fossil fuel reserves.
The Light Water Breeder Reactor (LWBR) core completed operation in 1982 after which the core was removed and destructively analyzed to confirm its breeding performance. This analysis showed that the breeding of uranium-233 from the inexpensive thorium was successful with a breeding ration of 1.01.
Over its 25-year life, the Shippingport power plant operated for about 80,324 hours, produced about 7.4 billion kilowatt-hours of electricity.
TECHNOLOGICAL ADVANCES
The program continues to devote considerable resources to improving the technology for naval nuclear propulsion. This has included development of a number of pressurized water reactors of various power ratings to meet naval requirements for both submarines and major surface ships.
The reactors range from the smallest used to power the 372-ton deep submergence research vehicle, NR-1 (retired from service in 2008), to the largest used to power the 100,000 ton GERALD R. FORD class carriers. The program has consistently developed increasingly power and energy dense new reactor designs for high speed LOS ANGELES class attack submarines (1970's-1990's) , the OHIO class of Trident ballistic missile submarines (1970's- 1990's), SEAWOLF class attack submarines (1980's-1990's), VIRGINIA class attack submarines (2000's- today), and the OHIO class replacement, COLUMBIA class ballistic missile submarines (lead ship currently under construction). (3)
To minimize downtime for maintenance and to ensure that a high percentage of the nuclear powered fleet is ready for immediate deployment in an emergency, the program has emphasized increasing the lifetime of naval reactor cores. This lifetime has been extended from a two year life for the first NAUTILUS core to 10 - 15 year life for ships delivered in the 1970's, to today where submarine cores last the life of a ship (over 30-years). The GERALD R. FORD class aircraft carrier only needs to be refueled once in the 50+ year life of the ship. For perspective, this is similar to a D-size battery powering your car for nearly your entire driving life. (3)
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Technological advances also come in other fields such as advanced materials that resist cracking over the life of the ship, use of state of the art microprocessors and power electronics, and information technology to make it easier for operators to keep an intuitive understanding of how the plant is performing.
The Naval Nuclear Propulsion Program has also investigated other reactor approaches and continues to monitor developments in reactor design, but no type has been shown to be as suitable for naval application as the pressurized water reactor.
PERFORMANCE AND TESTING
In January, 1955, the NAUTILUS, the world's first nuclear propelled ship, went to sea. In 1958, NAUTILUS reached the North Pole. In 1960, the two-reactor: TRITON completed a submerged voyage around the world, surfacing only once to transfer a man who needed medical assistance. At the end of that year, the GEORGE WASHINGTON, the first Polaris Fleet Ballistic Missile (FBM) submarine, began its first patrol and initiated the U.S. sea-based strategic deterrent. Since then the nuclear fleet grew and today over 40 percent of the U.S. Navy's major combatants currently powered by nuclear power plants, the flexibility and high speed endurance of these ships have become an essential, integral element in U.S. naval operations. Nuclear powered submarines make long deployments in all areas of the world undetected. Ballistic missile submarines provide a secure strategic force and attack submarines are capable of anti-surface ship and anti-submarine warfare. The nuclear powered aircraft carriers provide an unmatched naval strike force that can operate for extended periods in remote regions, such as the Indian Ocean, without concern for fuel supply. These forces can move rapidly to other trouble areas if required in the national interest.
The Naval Nuclear Propulsion Program has over 7,500 reactor years of cumulative reactor operation, and nuclear powered ships have steamed over 175 million miles. Since the inception of the program, there has never been an accident involving a naval reactor nor a release of radioactivity to the environment which has adversely affected public health or safety. This testifies to the reliability and effectiveness of the nuclear powered fleet. (3)
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An important factor in the technical accomplishments of the Naval Nuclear Propulsion Program has been the emphasis on continuity, experience and technical expertise in personnel. The headquarters staff currently consists of several hundred engineers and scientists with over 2400 cumulative years of experience in naval nuclear propulsion. The most senior 100 people have an average of about 15 years of experience and the 20 division heads have an average of about 20 years of experience, having served in many technical areas including field positions. This same emphasis on personnel competence and technical qualification exists in the other areas of the program both within the operating forces and in the activities that perform research, design, development, construction, maintenance, overhaul and refueling of nuclear powered ships. For example, since the beginning of the program, over 142,000 officers and enlisted technicians have gone through an intensive program that consists of six months instruction in theoretical knowledge at the Navy's Nuclear Power School, six months practical experience operating one of the naval nuclear reactors and propulsion plants, and an additional period to become qualified to operate the nuclear propulsion plant of the ship to which they have been assigned. (3)
DESIGN AND ENGINEERING
Because a warship must be able to perform its mission and return under combat conditions, the nuclear propulsion plant therefore must be engineered to survive battle damage and severe shock; to operate reliably and safely in close proximity to the crew; and to be repaired at sea by the crew if necessary. Standards for materials and systems are rigorous and only premium products with a proven pedigree are used in the reactor to minimize maintenance and take maximum advantage of long core lives. Building and operating effective naval nuclear propulsion plants involves many engineering and design considerations. Rickover drove the following important tenets of the program's engineering philosophy:
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Avoid committing ships and crews to highly developmental and untried systems and concepts.
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Ensure adequate redundancy in design so that the plant can accommodate, without damage to ship or crew, equipment or system failures that inevitably will occur.
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Minimize the need for operator action to accommodate expected transients. If the plant is inherently stable, the operator is better able to respond to unusual transients.
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Simplify system design so as to be able to rely primarily on direct operator control rather than on automatic control.
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Select only materials proven by experience for the type of application intended and insofar as practicable, those that provide the best margin for error in procurement, fabrication, and maintenance.
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Require suppliers to conduct extensive accelerated life testing of critical reactor and systems components to ensure design adequacy prior to operational use shipboard plant.
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Confirm reactor and equipment design through extensive analyses, full scale mockups, and tests.
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Use specially trained inspectors and extensive inspections during manufacture; accept only equipment that meets specification requirements.
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Concentrate on designing, building and operating the plants so as to prevent accidents, not just cope with accidents that could occur.
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Another important aspect of NR design activities is that for new ship designs, NR takes the lead for not just the reactor plant (systems directly associated with operation and control of the reactor and production of steam for use in propulsion turbines or electricity generation) but also for the entire propulsion plant including propulsion turbines and electric generation /distribution. This is because design, reliability, and maintainability of the rest of the propulsion plant can affect the operation of the reactor plant.
CRADLE TO GRAVE
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The Naval Reactors maintains responsibility from cradle to grave - meaning from initial design through to ultimate disposal. This ultimate disposal for submarines involves defueling the reactor, inactivating the ship, removing the reactor compartment, recycling the rest of the submarine to maximum extent practicable, and disposing of non-recyclable portions. The key elements of Naval Reactor's disposal responsibilities are the expended fuel and the reactor compartment.
After expended fuel is removed from the reactor it is put in robust shipping containers that are designed to survive the most severe of accident conditions. These shipping containers are placed on railcars and shipped to the expended core facility in Idaho. Nearly 1,000 expended fuel container shipments have been safely made since 1957. Once the shipping container arrives at the Naval Reactors Facility, the expended fuel is unpacked, visual inspected, and then repacked suitably for a geological repository. Naval Reactors is currently building the replacement for the Expended Core Facility at NRF - the new facility is the Spent Fuel Handling Facility (also at NRF) and is expected to be operational in 2027.
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Some naval spent nuclear fuel is given more detailed examinations for such purposes as confirming the adequacy of new design features, exploring material performance concerns, and obtaining detailed information to confirm or adjust computer predictions of naval nuclear core performance attributes.
The removed reactor compartments (with nuclear fuel removed) are shipped on barges to the final disposal site at the DOE Hanford site. During shipment, the Coast Guard or the Navy will provide an escort vessel to ensure the security of the barge.
Learn more about Spent Fuel Handling Facility
FACILITIES AND ORGANIZATION
The Naval Nuclear Propulsion Program encompasses an extensive and highly integrated network of facilities and activities devoted to work on naval nuclear propulsion plants. The scope of program work includes research, development, design, procurement, specification, construction, inspection, installation, certification, testing, overhaul, refueling, operational practices and procedures, maintenance, supply support, and ultimate disposition of naval nuclear propulsion plants, including components thereof, and any special maintenance and servicing facilities related thereto. Because the program work involves highly sensitive information and requires close control and review by management and senior personnel, much of the work is done at facilities exclusively devoted to the program.
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The Director of the Naval Nuclear Propulsion Program oversees and manages all aspects of the program. These functions are discharged through the headquarters and field office organizations which are under the direct control of the Director, and which administer and control all aspects of naval nuclear propulsion and other assigned nuclear work. The major facilities involved in the Naval Nuclear Propulsion Program include the following:
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Bettis Atomic Power Laboratory (Bettis) and Knolls Atomic Power Laboratory (Knolls), two facilities which are owned by the Department of Energy and operated by private contractors.
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A naval reactor land-based prototype sites and a site with moored-training ships.
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Two private and three Navy shipyards. The private shipyards perform ship and propulsion plant design work, and build nuclear powered ships. The Navy shipyards and private shipyards support industrial work on ships for significant maintenance or modernization.
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A private contractor organization which is exclusively devoted to procuring reactor plant and related equipment for the program, as well as providing technical and logistics support for installed reactor plant equipment to the operating fleet. In addition, the Navy Supply system provides repair parts support, warehousing facilities and data processing service in support of reactor plant equipment.
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Over 800 private firms which build and provide services on the equipment (including the nuclear cores) installed in the nuclear propulsion plants aboard nuclear powered ships.
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In addition to these facilities, the program exercises technical control over or provides technical input to other activities involved in naval nuclear propulsion. These include the Nuclear Field 'A' School and Navy Nuclear Power School in Charleston South Carolina, which receives technical direction and oversight from headquarters; Navy nuclear support and supply facilities which, using technical requirements promulgated by headquarters, service and provide operational support to the nuclear propulsion plants of ships; and the Expended Core Facility, which is used to conduct technical examinations of spent fuel.
The ability to perform nuclear propulsion work has been built up over more than 75-years. Substantial effort and funds have gone into developing the laboratories, prototype plants, shipyards, specialized facilities, such as the Expended Core Facility, and vendor plants producing the entire spectrum of nuclear components. These facilities are a national industrial asset of the highest technical quality and capability. The personnel who man these facilities represent an extraordinary pool of talented personnel, highly trained and experienced in meeting the exacting technical and quality control requirements necessary to produce and maintain a nuclear propulsion plant. This commitment of personnel and facilities is necessary for the continued successful application of nuclear propulsion to Navy ships.
NAVAL REACTORS HEADQUARTERS (NRHQ)
The Naval Nuclear Propulsion Program headquarters organization employs both civilians and naval officers, jointly assigned to the Department of Energy and the Department of the Navy. The headquarters organization is the central authority for all
aspects of the program. Significant technical and administrative decisions are made by the headquarters professional staff with input from other segments of the program. In addition, the headquarters organization maintains close contact with all activities involved in naval nuclear work, including regulating many aspects of the work and controlling the interface between program activities and other government agencies. The engineering staff at headquarters has a common technical and engineering background that includes post-graduate level courses in nuclear and mechanical engineering provided by the Bettis Atomic Power Laboratory. The headquarters staff is about 1/10th the size of the Nuclear Regulatory Commission while overseeing about the same number of reactors, but in addition to serving regulatory function the Naval Reactors headquarters also oversees R&D, plant design, operator training, maintenance, and eventual disposal.
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The headquarters organization is divided into technical divisions and project offices. Each technical division has a major technical area of expertise related to naval nuclear propulsion, and is headed by a senior technical manager with many years of engineering experience in the program. Each project office controls a total project and is responsible for ensuring coordination among the different technical divisions conducting work on that project. A senior technical manager with many years of program experience heads each project office.
The technical divisions and project offices are supported by a separate headquarters group which administers program logistics, financial, budget, and procurement functions. In addition, other headquarters groups provide oversight for Navy nuclear propulsion training activities, nuclear safeguards, security, public and foreign affairs, congressional matters and other aspects of program work.
Reporting to the Director are a number of program field offices which oversee all aspects of the work and ensure that the policies, decisions and requirements of the headquarters organization are properly implemented and complied with. The field offices are responsible solely to the Director and are devoted exclusively to the Naval Nuclear Propulsion Program. The head of each field office is a senior representative with broad experience in the program including in most cases experience at headquarters. The staffs of the field offices include other senior civilian representatives, naval officers and professional personnel with special experience and qualifications in the program.
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In addition to directing all aspects of the program at the laboratories,shipyards, training activities, procurement and support operations and field offices, the headquarters organization deals directly with other Navy, DOD and DOE organizations and with other Federal and State agencies on matters related to or affecting the program. Examples include the Department of State, the Nuclear Regulatory Commission, the Environmental Protection Agency, and the Office of Personnel Management. In similar fashion, the headquarters organization also coordinates the interface between program activities (such as the field offices and shipyards) and Federal or State agencies and private companies on matters related to or affecting the program.
Primary References:
(1) Rickover's Final Testimony before Congress in 1982 - This article incorporates text from this source, which is in the public domain. This is the source unless otherwise noted.
(2) Naval Reactors - Report on Low Enriched Uranium for Naval Reactors Cores, 2014
(3) Naval Reactors - Gray Book, 2020
(4) Bettis Shippingport Report (1993 WAPD-T-3007), 1993
(5) Rickover and the Nuclear Navy Francis Duncan
(6) https://www.epa.gov/radtown/nuclear-submarines-and-aircraft-carriers
(7) https://www.energy.gov/sites/default/files/2016/09/f33/EIS-0453-FEIS_Volume_I.pdf
(8) https://www.nr-ha.org/books-sources/1963-nr-program---a-joint-navy-aec-program---history
(10) Carol O. Holmquist and Russell S. Greenbaum, “The Development of Nuclear Propulsion in the Navy” (United States Naval Institute
(11) Daniel Parry - NRL History - Phil Abelson The Atomic Age Proceedings, Vol. 86, No. 9)
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Timeline
1946 - 1949
1950 - 1959
1960 - 1969
1970 - 1979
1980 - 1989
1990 - 1999
2000 - 2009
2010 - 2019
2020 - 2029
Jun 1946 - Rickover + 5 other Naval Officers go to Oak Ridge to study
Aug 1948 - Navy BuShips forms the Nuclear Power Branch
Dec 1948 - STR (Nautilus ) Project Started
Jun 1949 - MIT starts nuclear power course
Aug 1950 - Truman authorizes Nautilus sets Jan 1955 sea date
Jun 1952 - Keel Laid for Nautilus
Dec 1952 - NR teams goes to help with Canada NRX reactor accident
Mar 1953 - STR-1 (Nautilus prototype) initial criticality
Jul 1953 - 1st Commercial nuclear power plant (Shippingport) assigned to NR
Jan 1955 - Nautilus puts to sea for 1st time
Feb 1957 - 2nd sub class (Seawolf) initial sea trials
Apr 1957 - Nautilus refueled after 62,562 miles
Oct 1957 - 3rd sub class (Skate) initial sea trials
Nov 1957 - Order placed for 1st nuclear aircraft carrier
Dec 1957 - First commercial electricity from Shippingport
Mar 1958 - 4th Sub class (Skipjack) initial sea trials
Mar 1958 - Skate surfaces at North Pole
May 1958 - Shippingport commissioned for commercial operation
Jul 1958 - US-UK Mutual Defense Agreement signed
Dec 1958 - Seawolf starts conversion from sodium to PWR
Jul 1959 - Rickover visits USSR
Feb 1960 - Triton starts continuous submerged round the world cruise
Nov 1960 - 1st Polaris submarine patrol (66 days)
Nov 1960 - Tullibee turbo-electric submarine commissioned
Jan 1961 - Army Reactor SL-1 Accident at INL
Sep 1961 - 1st nuclear cruiser (CGN-9) commissioned
Nov 1961 1st CVN (Enterprise) commissioned
Oct 1962 - CGN-25 (Bainbridge) commissioned
Apr 1963 - Polaris Sales Agreement between US & UK signed
Mar 1967 - 1st Sturgen class (637) commissioned
May 1967 - CGN-35 (Truxtun) commissioned
May 1968 - Scorpian lost at sea
May 1969 - SSN 665 (Guitarro) sinks at pier at Mare Island during construction
Jul 1969 - Narwhal SSN-671 (natural circulation reactor) commissioned
Aug 1969 - NR-1 goes to sea
Jul 1970 - NR Moves from Main Navy to NC-2 in Crystal City, VA
Feb 1974 - 1st CGN-36 class (California) cruiser commissioned
Dec 1974 - Lipscomb SSN-685 (2nd design turbo-electric) submarine commissioned
Mar 1975 - 1st Nimitz class aircraft carrier (CVN 68) commissioned
Nov 1976 - 1st Los Angeles class fast attack submarine commissioned
Dec 1973 - Rickover made full admiral
Sep 1976 - 1st CGN-38 class (Virginia) cruiser commissioned
Aug 1977 - Shippingport initial criticality with breeder core
Aug 1973 - NR 25th Anniversary
Mar 1979 - Three Mile Island Accident
May 1979 - Nautilus deactivated
Mar 1980 - Nautilus Inactivated
Feb 1982 - Admiral Rickover retires and is replaced by Admiral McKee
Oct 1982 - Shippingport Power Plant shuts down for last time
Nov 1981 - 1st Ohio class ballistic missile submarine commissioned
July 1985 - 1st Flight II Los Angeles Class submarine commissioned with advanced core
Jul 1985 - Nautilus opens as National Historic Landmark
Jan 1986 - Space Shuttle Challenger Disaster
Apr 1986 - Chernobyl Accident
Jul 1986 - Rickover dies at age 86
Oct 1988 - Admiral McKee retires and is replaced by Admiral DeMars
Dec 1991 - Dissolution of Soviet Union
May 1995 - 1st nuclear cruiser (CGN-9) inactivated
Oct 1995 - Settlement Agreement between DOE and Idaho Signed
Sep 1996 - Admiral DeMars retires and is replaced by Admiral Bowman
Sep 1996 - Last SSN 688 class submarine (SSN 773) commissioned
Sep 1997 - Last OHIO Class submarine (SSBN 743) commissioned
July 1997 - 1st SEAWOLF class submarine commissioned
Aug 1998 - NR 50th Anniversary
Jul 1999 - Last 2 nuclear cruisers (CGN-36 & 37) inactivated
Jan 2000 - NR moves from NC-2 Crystal City to Washington Navy Yard
Jan 2001 - Ehimu Maru/SSN772 Collision
Feb 2003 - Space Shuttle Columbia Disaster
June 2008 - 2008 Addendum to 1995 Settlement Agreement Signed
Aug 2004 - NR Assigned lead for NASA Prometheus reactor
Oct 2004 - 1st VIRGINIA class submarine (SSN 774) commissioned
Nov 2004 - Admiral Bowman retires and is replaced by Admiral Donald
Jan 2005 - SSN 711 strikes seamount (no damage to reactor plant)
Nov 2008 - NR-1 Inactivated
Jan 2009 - Last Nimitz class aircraft carrier (CVN 77) commissioned
Mar 2011 - Fukushima Accident
May 2012 - SSN-755 fire at Portsmouth Naval Shipyard (ship eventually scrapped)
Nov 2012 - Admiral Donald retires and is replaced by Admiral Richardson
Dec 2012 - Enterprise (CVN 65) Inactivated
Dec 2013 - Admiral McKee dies as age 84
Aug 2015 - Admiral Richardson becomes CNO and is replaced by Admiral Caldwell
Jul 2017 - 1st FORD Class aircraft carrier (CVN 78) commissioned
Nov 2020 - 1st two Columbia class ballistic missile submarines (SSBN 826 & 827) ordered
Dec 2021 - SSN 22 hits sea mount in South China Sea
Jan 2024 - Admiral Caldwell retires and is replaced by Admiral Houston
Feb 2024 - Admiral DeMars dies at age 88