Nuclear marine propulsion in the context of "Nuclear reactor"

Marine propulsion is the mechanism or system used to generate thrust to move a watercraft through water. While paddles and sails are still used on some smaller boats, most modern ships are propelled by mechanical systems consisting of an electric motor or internal combustion engine driving a propeller, or less frequently, in pump-jets, an impeller. Marine engineering is the discipline concerned with the engineering design process of marine propulsion systems.

Human-powered paddles and oars, and later, sails were the first forms of marine propulsion. Rowed galleys, some equipped with sail, played an important early role in early human seafaring and warfare. The first advanced mechanical means of marine propulsion was the marine steam engine, introduced in the early 19th century. During the 20th century it was replaced by two-stroke or four-stroke diesel engines, outboard motors, and gas turbine engines on faster ships. Marine nuclear reactors, which appeared in the 1950s, produce steam to propel warships and icebreakers; commercial application, attempted late that decade, failed to catch on. Electric motors using battery packs have been used for propulsion on submarines and electric boats and have been proposed for energy-efficient propulsion.

An aircraft carrier is a warship that serves as a seagoing airbase, equipped with a full-length flight deck and hangar facilities for supporting, arming, deploying and recovering shipborne aircraft. Typically it is the capital ship of a fleet (known as a carrier battle group), as it allows a naval force to project seaborne air power far from homeland without depending on local airfields for staging aircraft operations. Since their inception in the early 20th century, aircraft carriers have evolved from wooden vessels used to deploy individual tethered reconnaissance balloons, to nuclear-powered supercarriers that carry dozens of fighters, strike aircraft, military helicopters, AEW&Cs and other types of aircraft such as UCAVs. While heavier fixed-wing aircraft such as airlifters, gunships and bombers have been launched from aircraft carriers, these aircraft do not often land on a carrier due to flight deck limitations.

The aircraft carrier, along with its onboard aircraft and defensive ancillary weapons, is the largest weapon system ever created. By their tactical prowess, mobility, autonomy and the variety of operational means, aircraft carriers are often the centerpiece of modern naval warfare, and have significant diplomatic influence in deterrence, command of the sea and air supremacy. Since the Second World War, the aircraft carrier has replaced the battleship in the role of flagship of a fleet, and largely transformed naval battles from gunfire to beyond-visual-range air strikes. In addition to tactical aptitudes, it has great strategic advantages in that, by sailing in international waters, it does not need to interfere with any territorial sovereignty and thus does not risk diplomatic complications or conflict escalation due to trespassing, and obviates the need for land use authorizations from third-party countries, reduces the times and transit logistics of aircraft and therefore significantly increases the time of availability on the combat zone.

The French Navy (French: Marine nationale, pronounced [maʁin nɑsjɔnal], lit. 'National Navy'), informally La Royale (French pronunciation: [la ʁwajal], lit. 'The Royal [One]'), is the maritime arm of the French Armed Forces and one of the four military service branches of France. It is among the largest and most powerful naval forces in the world recognised as being a blue-water navy. The French Navy is capable of operating globally and conducting expeditionary missions, maintaining a significant overseas presence. The French Navy is one of eight naval forces currently operating fixed-wing aircraft carriers, with its flagship Charles de Gaulle being the only nuclear-powered aircraft carrier outside the United States Navy, and one of two non-American vessels to use catapults to launch aircraft.

Founded in the 17th century, the French Navy is one of the oldest navies still in continuous service, with precursors dating back to the Middle Ages. It has taken part in key events in French history, including the Napoleonic Wars and both world wars, and played a critical role in establishing and securing the French colonial empire for over 400 years. The French Navy pioneered several innovations in naval technology, including the first steam-powered ship of the line, first seagoing ironclad warship, first mechanically propelled submarine, first steel-hulled warship, and first armoured cruiser.

Enriched uranium is a type of uranium in which the percent composition of uranium-235 (written U) has been increased through the process of isotope separation. Naturally occurring uranium is composed of three major isotopes: uranium-238 (U with 99.2732–99.2752% natural abundance), uranium-235 (U, 0.7198–0.7210%), and uranium-234 (U, 0.0049–0.0059%). U is the only nuclide existing in nature (in any appreciable amount) that is fissile with thermal neutrons.

Enriched uranium is a critical component for both civil nuclear power generation and military nuclear weapons. Low-enriched uranium (below 20% U) is necessary to operate light water reactors, which make up almost 90% of nuclear electricity generation. Highly enriched uranium (above 20% U) is used for the cores of many nuclear weapons, as well as compact reactors for naval propulsion and research, as well as breeder reactors. There are about 2,000 tonnes of highly enriched uranium in the world.

A nuclear-powered icebreaker is an icebreaker with an onboard nuclear power plant that produces power for the vessel's propulsion system. Although more expensive to operate, nuclear-powered icebreakers provide a number of advantages over their diesel-powered counterparts, especially along the Northern Sea Route where diesel-powered icebreaker operations are challenging due to the heavy power demand associated with icebreaking, limited refueling infrastructure along the Siberian coast, and the endurance required. As of 2025, Russia is the only country that builds and operates nuclear-powered icebreakers, having built a number of such vessels to aid shipping along the Northern Sea Route and Russian arctic outposts since the Soviet era.

USS Ronald Reagan (CVN-76) is a Nimitz-class, nuclear-powered supercarrier in the service of the United States Navy. The ninth ship of her class, she is named in honor of Ronald Reagan, President of the United States from 1981 to 1989. She was built at Newport News Shipbuilding in Newport News, Virginia, and was commissioned on 12 July 2003.

Ronald Reagan made five deployments to the Pacific and Middle East between 2006 and 2011 while based at Naval Air Station North Island. In October 2015, Ronald Reagan replaced USS George Washington as the flagship of Carrier Strike Group 5, the only forward-based carrier strike group homeported at Yokosuka, Japan, as part of the United States Seventh Fleet. Since 2016, Ronald Reagan has embarked on short annual summer patrols of the Western Pacific in the United States Seventh Fleet area of operation.

Charles de Gaulle (R91; French: [ʃaʁl(ə) də ɡol] ) is the flagship of the French Navy. Commissioned in 2001, the ship is the tenth French aircraft carrier, the first French nuclear-powered surface vessel, and the only nuclear-powered carrier completed outside of the United States Navy. She is named after French president and general Charles de Gaulle.

The ship carries a complement of Dassault Rafale M and E-2C Hawkeye aircraft, AS365F Dauphin Pedro, EC725 Caracal and AS532 Cougar helicopters for combat search and rescue, as well as modern electronics and Aster missiles. She is a CATOBAR-type carrier that uses two 75 m (246 ft) C13‑3 steam catapults of a shorter version of the catapult system installed on the US Nimitz-class aircraft carriers, one at the bow and one at the waist. As of July 2025, Charles de Gaulle was the only non-American carrier-vessel that had a catapult launch system, which has allowed for operation of F/A-18E/F Super Hornets and C-2 Greyhounds of the United States Navy.