first nuclear submarine - USS Nautilus-Courtesy Argonne National Laboratory

The world’s first nuclear submarine

The world’s first nuclear-powered submarine was the USS Nautilus. It was commissioned at Groton, Connecticut, USA, on the 30th of September 1954, with Commander Eugene P. Wilkinson as the boat’s first commander.

Before nuclear-powered engines, diesel-powered submarines could only stay underwater for 48 hours and had to return to a port to refuel. A nuclear submarine was a different beast: it could stay underwater for 2 weeks.

first nuclear submarine - USS Nautilus-Courtesy Argonne National Laboratory
First nuclear submarine – USS Nautilus – Courtesy Argonne National Laboratory

This made the USS Nautilus the ideal candidate to undertake “Operation Sunshine”, a trip to the north pole that President Eisenhower ordered to demonstrate the potential of the soon-to-come military technology of “submarine-launched ballistic missiles” (SLBMs).

Nuclear submarines offer many other significant advantages over conventional submarines. For example, the nuclear reactor allows a submarine to operate at high speed for a long time. Crews had to start stocking much more food for these longer journeys!

Design and development

In March 1950, the initial design phase of the world’s first nuclear submarine began as project SCB 64. The US Congress authorised the construction of a nuclear-powered submarine for the US Navy in July 1951, which was planned and supervised by Captain Hyman G. Rickover.

On the 12th of December 1951, the US Navy announced that the submarine would be called Nautilus.

The Nautilus was powered by the Submarine Thermal Reactor, later redesignated as the S2W reactor, a pressurised water reactor produced for the US Navy by Westinghouse Electric Corporation. The Bettis Atomic Power Laboratory, which Westinghouse operated, was tasked with designing a nuclear power plant for a submarine on the 31st of December 1947. As a result, they developed the fundamental reactor plant design, which was used in the Nautilus.

After being commissioned on September 30th 1954, the Nautilus underwent further construction and testing while docked. However, on January 17th 1955, the submarine began operating on nuclear power and underwent sea trials. The “nuclear navy” was born.

Capabilities and performance

On May 10th 1955, the Nautilus set off for shakedown, travelling south after receiving preliminary acceptance by the Navy. During the route to Puerto Rico, the Nautilus:

  • set a new record for a submarine’s most extended submerged cruise, travelling 1,381 miles in 89.8 hours.
  • achieved the highest sustained submerged speed recorded for over one hour.

The USS Nautilus broke numerous submarine travel records in its early years of service. In August 1958, it accomplished the first voyage under the geographic North Pole.

The Nautilus travelled almost 500,000 miles in its 25 years lifespan.

Where is USS Nautilus today?

In March 1980, the USS Nautilus was decommissioned, and the reactor equipment was removed. It was designated a National Historic Landmark in 1982 and now lives at the Submarine Force Library and Museum in Groton, Connecticut, receiving about 250,000 visitors annually.

How does a nuclear submarine work?

Onboard nuclear reactors power a nuclear submarine, and the atoms in the nuclear reactor split, releasing energy as heat. The heat creates steam in the heat exchanger, which is fed into a turbine, which turns a generator to produce electricity. The turbines also make electricity for the submarine, and as the steam cools and condenses back into the water, the water is directed back through the system, and the process starts again.

As with all forms of nuclear power, the engine releases radiation. The crew on the submarine must be shielded for safety, and crew are prohibited from accessing the reactor during operation. The reactor engineers follow strict safety procedures and must wear radiation monitors that are checked regularly to ensure they are not exposed to radiation.

Why are heat exchangers critical in nuclear submarines?

Without a properly functioning heat exchanger, a nuclear submarine could not convert the reactor’s heat into energy that turns into steam. This would make it impossible for the submarine to operate its systems and move through the water. The heat exchanger is essential in ensuring the nuclear submarine can work.

If you’d like to find out more about heat exchange in submarines, read our guide about the challenges of cooling submarine generators and motors.

We design and manufacture heat exchangers for submarines

Photo of Titanium air coolers and oil cooler for the defence sector designed and manufactured by Sterling Thermal TechnologyHeat exchangers are a vital part of a submarine. At Sterling TT, we have decades of experience designing and producing high-quality heat exchangers tailored explicitly for the defence industry.

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