The U.S. Navy aircraft carrier USS John F. Kennedy is launched by Jacqueline Kennedy and her daughter Caroline.
Ceremonial ship launching involves the performance of ceremonies associated with the process of transferring a vessel to the water. It is a nautical tradition in many cultures, dating back thousands of years, to accompany the physical process with ceremonies which have been observed as public celebration and a solemn blessing, usually but not always, in association with the launch itself.
Ship launching imposes stresses on the ship not met during normal operation and, in addition to the size and weight of the vessel, represents a considerable engineering challenge as well as a public spectacle. The process also involves many traditions intended to invite good luck, such as christening by breaking a sacrificial bottle of champagne over the bow as the ship is named aloud and launched.
An aircraft carrier is a warship that serves as a seagoing airbase, equipped with a full-length flight deck and facilities for carrying, arming, deploying, and recovering aircraft. Typically, it is the capital ship of a fleet, as it allows a naval force to project air power worldwide without depending on local bases for staging aircraft operations. Carriers have evolved since their inception in the early twentieth century from wooden vessels used to deploy balloons to nuclear-powered warships that carry numerous fighters, strike aircraft, helicopters, and other types of aircraft. While heavier aircraft such as fixed-wing gunships and bombers have been launched from aircraft carriers, one has yet to successfully land on one. By its diplomatic and tactical power, its mobility, its autonomy and the variety of its means, the aircraft carrier is often the centerpiece of modern combat fleets. Tactically or even strategically, it replaced the battleship in the role of flagship of a fleet. One of its great advantages is that, by sailing in international waters, it does not interfere with any territorial sovereignty and thus obviates the need for overflight authorizations from third-party countries, reduces the times and transit distances of aircraft and therefore significantly increase the time of availability on the combat zone.
There is no single definition of an "aircraft carrier", and modern navies use several variants of the type. These variants are sometimes categorized as sub-types of aircraft carriers, and sometimes as distinct types of naval aviation-capable ships. Aircraft carriers may be classified according to the type of aircraft they carry and their operational assignments. Admiral Sir Mark Stanhope, RN, former First Sea Lord (head) of the Royal Navy, has said, "To put it simply, countries that aspire to strategic international influence have aircraft carriers." Henry Kissinger, while United States Secretary of State, also said: "An aircraft carrier is 100,000 tons of diplomacy."
As of March 2022, there are 47 active aircraft carriers in the world operated by fourteen navies. The United States Navy has 11 large nuclear-powered fleet carriers—carrying around 80 fighters each—the largest carriers in the world; the total combined deck space is over twice that of all other nations combined. As well as the aircraft carrier fleet, the US Navy has nine amphibious assault ships used primarily for helicopters, although these also each carry up to 20 vertical or short take-off and landing (V/STOL) fighter jets and are similar in size to medium-sized fleet carriers. The United Kingdom and China each operate two aircraft carriers. France, India, and Russia each operate a single aircraft carrier with a capacity of 30 to 60 fighter jets. Italy operates two light fleet carriers and Spain operates one. Helicopter carriers are operated by Japan (4, two of which are being converted to operate V/STOL fighters), France (3), Australia (2), Egypt (2), South Korea (2), China (2), Thailand (1) and Brazil (1). Future aircraft carriers are under construction or in planning by Brazil, China, France, India, Russia, South Korea, Turkey and the US.