aircraft carrier

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A large naval vessel designed as a mobile air base, having a long flat deck on which aircraft can take off and land at sea.

Invented by the British during World War I, the aircraft carrier was adopted by the United States and Japan as an experimental weapon to augment the battle line. In contrast to the Japanese, whose fleet and carriers were designed for defensive operations in the western Pacific, the U.S. Navy planned for an offensive, transpacific war all the way to Japan and created the long‐legged “fast” (33‐knot) carrier to operate over those great distances. The navy first converted a collier (coaling ship) into the 11,050‐ton carrier Langley (CV‐1 “V” being the symbol for heavier‐than‐air craft), commissioned in 1922. Then it converted two battle‐cruiser hulls, as allowed by the Washington Naval Arms Limitation Treaty, into 36,000‐ton fast carriers of the Lexington class. While the 542‐foot Langley experimented with fighter and scout planes in fleet maneuvers during the 1920s, the navy developed dive‐bombers and torpedo planes for the new 888‐foot‐long carriers. As soon as the Lexington and the Saratoga joined the fleet, Adm. Joseph Mason Reeves placed squadrons of all four plane types aboard them, a total of eighty planes per carrier. With the Saratoga, he launched a successful surprise mock attack on the Panama Canal during Fleet Problem IX in 1929. This demonstration of offensive carrier air power established the foundation of U.S. carrier aviation for the rest of the century.

During the war games of the 1930s, similar aggressive attacks struck the Hawaiian Islands, including Pearl Harbor; West Coast seaports; and defending fleets and land‐based air forces. Traditional battleship admirals often minimized these achievements and argued for using the carriers with the battle line, but this only inhibited their mobility and made them vulnerable to air, ship, and submarine attacks. The Lexington‐class carriers mounted a defensive battery of eight 8‐inch and twelve 5‐inch guns. In fact, their own fighter planes and escorting gunships provided the surest defense. So newer carriers, built from the keel up as carriers, mounted only eight 5‐inch guns. Flight decks were made of wood so that bombs would not explode until they struck the hangar deck, enabling planes to keep operating during battle.

The stunning Japanese attack on Pearl Harbor by planes from six Japanese carriers on 7 December 1941 proved decisively the offensive power of fast carriers. It was, however, uncharacteristic of Japanese warships to operate so far from home waters. Adm. Ernest J. King, commander in chief of the U.S. Fleet, therefore instituted wide‐ranging offensive hit‐and‐run raids with the six available carriers to keep the Japanese off balance. Their most aggressive leader was Adm. William F. Halsey, who even launched James Doolittle's army bombers from the Hornet to strike Tokyo in April 1942. U.S. carriers won naval victories at the Battle of the Coral Sea in May, the Battle of Midway in June, and the battles around Guadalcanal between August and November, sinking several Japanese carriers—four at Midway alone. But one by one all U.S. carriers were sunk except for the Saratoga and the Enterprise, and even these two were heavily damaged. The reasons included imperfect tactics and damage control, inferior aircraft, inadequate numbers of fighter planes, ships, and antiaircraft guns, and insufficient reconnaissance.

These lessons were applied to the construction of two dozen new fast carriers of the Essex class, which entered the fleet in 1943. At 27,100 tons, the 872‐foot Essexes each embarked an air group of three squadrons: thirty‐six fighters, the superior F6F Hellcat; thirty‐six dive‐bombers, first the SBD Dauntless and later the SB2C Helldiver; and eighteen torpedo bombers, the TBF/TBM Avenger. All three types performed scouting functions too, but the greatest innovation for detecting enemy planes was the installation of shipboard search radar, enabling fighter director officers to coordinate their fighters out to 100 miles from the carrier. In addition, antiaircraft defenses included twelve 5‐inch/.38‐caliber guns and numerous 40mm and 20mm batteries on each carrier. Nine 11,000‐ton light carriers (CVL) of the 31‐knot Independence class, converted from cruiser hulls between 1941 and 1943, added additional offensive punch; each operated twenty‐four fighters and nine torpedo bombers. Circular screens of new escorting fast battleships, cruisers, and destroyers, all bristling with antiaircraft guns, surrounded the carriers in each tactical formation.

Organized in the Fast Carrier Task Force of some fifteen carriers and 1,000 planes, these carriers provided the overwhelming firepower that spearheaded the Central Pacific offensive of 1943–45. Their optimum effectiveness occurred under the sagacious leadership of Adm. Marc A. Mitscher as the fast carriers overcame virtually all enemy opposition. The only major changes were the introduction of four‐plane night fighter teams aboard each Essex, three carriers equipped primarily for night operations, and an increase of fighters, including the F4U Corsair, over bombing planes to counter the kamikazes, Japanese suicide planes. Only one of the new fast carriers was sunk, the light carrier Princeton, off Leyte.

In the Atlantic, to defeat Germany's U‐boats, the navy depended on small, slow 18‐knot escort carriers (CVE), eighty‐four of which were commissioned. There were four major classes of CVEs, some converted from oilers but most mass‐produced; they varied in size between 7,800 and 11,400 tons, and each carried a composite air group of nine fighters and twelve torpedo bombers. Operating primarily as an independent hunter‐killer group, each escort carrier worked in concert with its five destroyers and destroyer escorts to track down and sink most of the U‐boats destroyed between 1943 and 1945. Many of them also operated in the Pacific, where fighters outnumbered torpedo bombers in providing close air support during amphibious assaults. Light construction made the escort carriers especially vulnerable, and several were sunk by bombs, gunfire, submarine torpedoes, or kamikazes.

Three large (CVB) 45,000‐ton, Midway‐class carriers, commissioned after the war ended, featured armored flight decks in order to nullify bomb hits. Each had a 986‐foot flight deck and a 137‐plane air group of fighters and dive‐bombers. The future of the carrier and its vulnerability to nuclear weapons became a cause of bitter controversy in the late 1940s, a controversy complicated by interservice rivalry. The navy depended upon the older Essexes in the Korean War (1950–53). Their air groups were comprised of F4U fighter bombers, F9F jet fighters, and piston‐engine AD (later A‐1) Skyraider attack planes. Atomic bombs were first deployed aboard carriers in the early 1950s.

The Korean War and the menace of the Soviet Union served to stimulate new carrier construction. During the 1950s and 1960s eight attack carriers (CVA, later CV again) belonging to the Forrestal and Kitty Hawk/America classes were built. Each displaced 56,000 to 61,000 tons and had 1,046‐foot flight decks to accommodate new and heavier planes. Air groups (later air wings) were comprised of up to 100 fighters and attack planes, mostly jets. The major fighters were F‐8 Crusaders and F‐4 Phantoms IIs, the bombers A‐1s, A‐3 Skywarriors, A‐4 Skyhawks, A‐6 Intruders, and A‐7 Corsair IIs. Cruising endurance was greatly increased with the commissioning in 1961 of the first nuclear‐powered carrier (CVN), the 75,700‐ton Enterprise, which did not require refueling at sea. To deal with the large Soviet submarine force, thirteen Essexes were redesignated as antisubmarine carriers (CVS) between 1954 and 1973; these operated S‐2 Tracker pison‐engine search planes and H‐34 Seabat and H‐3 Sea King antisub helicopters. All of these carrier types and planes supported ground operations during the Vietnam War (1965–73). In addition, three converted Essexes acted as amphibious‐assault helicopter personnel carriers (LPH) during the 1960s, until superseded by the Iwo Jima (LPH) and Tarawa (LPA) classes (landing platform, helicopter or assault) built specifically for that purpose.

During the 1970s, doctrinal confusion and criticism over retention of the large and seemingly vulnerable attack carriers continued. They were retained because of repeated crises in the Middle East and the growing Soviet surface fleet, which though basically defensive, included a few carriers. Eight 81,600‐ton nuclear‐powered carriers of the Nimitz class with 1,089‐foot flight decks were added between the late 1960s and late 1990s to begin replacing older oil‐fueled ships. Each was accompanied by a protective screen of missile‐bearing escort ships and formed a carrier battle group. They provided the core of the offensive power projection that effectively deterred the Soviet Navy. F‐14 Tomcat fighters and F/A‐18 Hornet fighter attack planes joined the carriers during the 1970s and 1980s, respectively, along with S‐3 Viking antisub jet search planes to augment E‐2 long‐range early warning radar carrier aircraft.

Throughout the Cold War, attack carrier strength remained fairly constant between twelve and fifteen, but even the collapse of the Soviet Union in 1989–90 did not diminish the need for carriers to help deter and quell global tensions. Thus, six carriers participated during 1990–91 in the Persian Gulf War. The continuing requirement for such large numbers of these extremely versatile carriers has been governed by the fact that, generally, for every carrier operating on station, one is home‐ported undergoing refit and overhaul, and another is in transit to or from the operating area. In this way, the United States has maintained the long‐legged global reach of its naval power.

[See also Fighter Aircraft; Navy Combat Branches: Surface Forces; Navy Combat Branches: Naval Air Forces.]

Bibliography

• Stefan Terzibaschitsch, Aircraft Carriers of the U.S. Navy, 1980.
• Norman Friedman, Carrier Air Power, 1981.
• Stefan Terzibaschitsch, Escort Carriers and Aviation Support Ships of the U.S. Navy, 1981.
• Norman Friedman, U.S. Aircraft Carriers: An Illustrated Design History, 1983.
• Clark G. Reynolds, The Fighting Lady: The New Yorktown in the Pacific War, 1986.
• George C. Wilson, Supercarrier, 1986.
• Edward P. Stafford, The Big E, 1988 repr.
• Clark G. Reynolds, The U.S. Fleet‐in‐Being Strategy of 1942, The Journal of Military History, Vol. 58 (1994), pp. 103–118.
• Theodore Taylor, The Magnificent Mitscher, 1991 repr

A large warship equipped to serve as a base for aircraft that can take off from and land on its deck.

See the Introduction, Abbreviations and Pronunciation for further details.

For more information on aircraft carrier, visit Britannica.com.

Sometimes characterized as "floating cities," aircraft carriers are a potent symbol of America's strength as a superpower. Although nations ranging from the United Kingdom and Russia to Peru and Thailand have their light carrier and helicopter carriers, the large carriers of the United States are without parallel in ability and firepower. Carriers provide an important means of force projection from the continental United States to any theatre, no matter how hostile, and offer a floating platform for missions that include both combat and intelligence-gathering. As President William J. Clinton said during a visit to the carrier Theodore Roosevelt in the 1990s, "When word of crisis breaks out in Washington, it's no accident that the first question that comes to everyone's lips is, 'where is the nearest carrier?'"

Components in the Carrier Concept

The carrier is one of the leading means for force projection, or the ability to project an aggregation of military personnel from the continental United States (or another theatre) in response to military requirements. As long as it operates in international waters, a carrier needs no permission to conduct landings or overflights. These floating military bases constitute sovereign U.S. territory capable of moving over the oceans—70% of Earth's surface—in the service of U.S. interests.

Carriers make possible a variety of options. They may be used to insert forces ashore; on the other hand, their presence is so intimidating that they may be used simply to "show the flag," or remind hostile powers of the U.S. presence. They are capable of attacking airborne, sea borne, or land targets, and engage in sustained operations in support of other forces—for example, the ground forces deployed for Operation Iraqi Freedom in 2003.

Battle groups and air wings. National command authorities do not deploy carriers alone. Rather, the carrier is the center of a battle group, a force of a half-dozen or more ships. The carrier battle group, or CVBG, may be used to protect merchant or military shipping; to provide protection to a Marine amphibious source en route to, or arriving in, an objective area; or to establish a naval presence in support of national security interests

Members of a battle group may include at least one destroyer and one frigate, two attack submarines, two guided missile cruisers, one guided missile destroyer, and a logistical support ship. Destroyers and frigates are primarily for anti-submarine warfare, while attack submarines, as their name implies, attack both enemy submarines and ships. Both guided missile cruisers and destroyers are multi-mission surface combatants, the first type armed with Tomahawk cruise missiles for long-range strike capability, and the second equipped for anti-aircraft warfare. The logistical support ship is usually a combined ammunition, oiler, and supply vessel.

Additionally, the carrier—by definition—serves as a home base for a number of aircraft, known as the carrier air wing. These typically include three squadrons of F/A-18 Hornets, which are all-weather fighter and attack aircraft, and one squadron of F-14 Tomcats, made for fleet air defense and precision strikes against ground targets. Along with these are one squadron of S-3B Vikings, the primary overhead/mission tanker, which is equipped for day and night surveillance, electronic countermeasures, command/control/communications warfare, and search and rescue; one squadron of EA-6B Prowlers, which jams enemy radar, electronic data links, and communications; one squadron of E-2C Hawkeyes, all-weather tactical warning and control system aircraft; and one squadron of SH-60 Seahawks, twin-engine utility or assault helicopters.

Overview of a Modern Carrier

U.S. aircraft carriers fall into several groupings, the largest of which is the Nimitz class. Largest warships in the world, these measure 1,092 feet (332.9 m) from bow to stern, and 252 feet (76.8 m) across. As large as it is, the large U.S. carrier still does not provide enough room for takeoff and landing by conventional means; therefore, the carrier deck includes a number of items for these purposes, as well as for the storage of aircraft below decks.

The aircraft do not remain on the carrier's deck when not in use; rather, they rest in a cavernous hangar beneath the deck, to which they can be summoned by means of four deck-edge elevators, each of which is capable of moving two aircraft at a time. For taking off, aircraft are attached to catapults, which give them the necessary acceleration to go from a standing position to 165 miles per hour (265.5 kph) in just two seconds. The flight crew of the Nimitz-class aircraft carrier is capable of launching two aircraft and landing one every 37 seconds in daylight, or one per minute at night.

The flight crew itself is a choreographed team, or rather a group of teams, each distinguished by jackets of different colors that signify functions. To the pilot in the air, the most critical colors on the deck are the amber and red lights of the Fresnel lenses on deck. Depending on the angle of the light, the pilot knows if he is too low or too high, while red flashing lights automatically signal a wave-off, meaning that the pilot cannot land at that time. When landing, a plane catches an arresting cable using its tailhook, a hook bolted to an 8-foot (2.4 m) bar attached to the rear part of the aircraft. The tailhook can bring a plane from a speed of 150 miles an hour (241.4 klph) to a complete stop within just 320 feet (97.5 m).

Primary Flight Control, or "Pri-Fly," is the control tower for flights. Above it on the "island," the part of the carrier that sticks up above the flight deck, is the bridge, the command and control center of the carrier as a whole. On the bridge is always an officer of the deck (OOD), designated by the ship's commanding officer, who serves a four-hour watch. The OOD is responsible for all facets of the safety and operation of the ship, among which are navigation, ship handling, communications, and routine tests, and inspections. Also on the bridge are the helmsman, who steers the ship, and numerous other personnel.

Powered by two nuclear reactors with four geared steam turbines and four shafts, the Nimitz-class carrier is capable of spending at least half a year at sea, and more than a decade without refueling. Its ship's company exceeds 3,000, with almost 2,500 more on the air wing. Below decks is an entire city, complete with vast warrens of living spaces, dining halls that serve nearly 20,000 meals a day, a radio and television station, a barber shop, a library, gymnasium, a hospital and dentist office, shops, and a post office.

Evolution of the Carrier

At 11:01 a.m. on January 18, 1911, the U.S. Navy's Eugene Ely landed a Curtiss pusher aircraft on a specially built platform aboard the USS Pennsylvania. Thus, was born the concept of the aircraft carrier. On March 20, 1922, the Navy commissioned the Langley, its first carrier, built from a converted collier called the Jupiter. Later that year, as a result of the 1922 Washington Naval Limitation Treaty, which limited battleship inventories, Congress authorized the conversion of the unfinished battleships Lexington and Saratoga. In June 1934, the Ranger, the first ship built as an aircraft carrier, was commissioned.

During the interwar period, the aircraft carrier benefited from a number of innovations, most of them British in origin. For example, the Royal Navy introduced the idea of arresting wire (originally necessary because the flimsy World War I-era planes might blow overboard), as well as elevator lifts for stowing craft. Later innovations in catapults and landing lights would also come from the United Kingdom. The British and Americans were not the only forces building aircraft carriers; like the Americans, the Japanese, who had signed the Washington naval agreement, converted unfinished battleships to carriers.

Carriers figured heavily in World War II, particularly during operations in the Pacific theatre. The Japanese launched their attack on U.S. forces at Pearl Harbor in December, 1941, from carriers, and in May, 1942, the United States struck back decisively in the Battle of the Coral Sea, the first naval battle in which opposing fleets fought without their ships coming in sight of one another. A month later, the Battle of Midway proved one of the turning points in the war, and reinforced the concept of naval air support.

Postwar changes. By the end of World War II, the United States had commissioned more than 34 carriers, with several more made operational late in 1945. But it had also lost several such vessels, including the first two, the Langley and the Lexington. Following the war, the introduction of guided missiles revolutionized the nature of the carrier battle group, while nuclear fission replaced diesel power for the most advanced carriers.

Several British innovations—the angled landing strip, which made it possible for a jet to land far from parked aircraft, as well as the mirrored landing site and steam catapults—made it possible to build carriers capable of launching powerful aircraft and managing complex air missions. But as the Cold War progressed, it became clear that only extraordinary carriers could support the vessels' emerging threefold purpose: to deliver air strikes against targets on sea and land; to protect other ships at long range; and to support antisubmarine operations through their battle groups. Only a true world power could afford to build carriers big enough to perform all three tasks—a distinction that, in effect, separated the United States from the rest of the world.

With the launch of its 59th carrier, Forrestal, in 1959, the United States introduced the era of the very large carrier. The Forrestal included rectangular extensions on the rear part of the flight deck, which greatly expanded the deck area. Designers had also moved the elevators off to the side, so that they could be used even as aircraft were taking off and landing.

Two years later, in 1961, the Navy introduced the first nuclear-powered carrier, the Enterprise. It is no accident that the world's most well-known fictional spaceship, from the 1960s television show Star Trek, was also called the Enterprise. During that era, the standard of excellence among carriers—the epitomy of technological superiority anyone was likely to encounter in real life—was the Enterprise, which carried 100 aircraft, displaced 75,700 tons (68,674 tonnes), and moved at speeds higher than 30 knots (55.6 kph). With eight nuclear reactors, it could travel for three years before being replaced.

As impressive as it was, the Enterprise would be eclipsed by the Nimitz (commissioned in May 1975) and the rest of its class. Instead of eight reactors, these required only two, whose uranium cores needed to be replaced once every 13 years. The carriers displaced 81,600 tons, but had much smaller propulsion systems, and thus, could store much more aircraft fuel.

As of 2003, the United States had launched a total of 75 carriers, with two more under construction. Its 12 active carriers included the Enterprise and the Kitty Hawk class (the Kitty Hawk and Constellation), all launched in 1961; the John F. Kennedy, launched in 1968; and eight carriers of the Nimitz class: Nimitz, Dwight D. Eisenhower (1977), Carl Vinson (1982), Theodore Roosevelt (1986), Abraham Lincoln (1989), George Washington (1992), John C. Stennis (1995), and Harry S. Truman (1998). Additionally, the Ronald Reagan was under construction, with launch planned for the middle of the decade, while construction was to begin on the George H. W. Bush, with completion planned for 2009. (Both are Nimitz-class carriers.)

Other nations and light carriers. The United States has decommissioned about as many carriers—63—as the rest of the world had afloat in 2003. Nations with carriers included the United Kingdom, France, Russia, China, Italy, Japan, Spain, India, Brazil, Chile, Peru, China, and Thailand. The leading carrier power, other than the United States, was—not surprisingly, given the many previous British achievements in carrier design—the United Kingdom. In part to facilitate the building of smaller and more economical carriers, the British in the late 1960s developed the Harrier jet, which takes off almost vertically. As of 2003, its fleet included three small carriers of the Invincible class, built for vertical/short takeoff and landing (V/STOL), each capable of carrying eight Harriers and from 10 to 12 helicopters.

France built the Charles de Gaulle, a nuclear-powered vessel that could carry 40 planes, as well as the Jeanne d'Arc helicopter carrier. The latter type of ship, midway of a carrier and a cruiser, provided a means of giving several nations carrier capabilities. Such was the case with the Russian Federation, which had a large helicopter carrier, the Gorshkov, along with a semi-active multi-role carrier, the Kutznetsov. As the Soviet Union, Russia was slow to develop carriers, in part because it lacked sufficient ports worldwide. By the late 1960s, however, the Soviets had begun to build aviation cruisers of the Moskva class. These have all been decommissioned since then, however. The world's other superpower, China, has a small naval carrier force, consisting primarily of the Shichang multi-role support ship.

Other notable naval powers include Italy, which had six carriers, helicopter carriers, or amphibious assault ships either in operation or under construction in 2003. These included the Andrea Doria, scheduled for completion in 2007. Built along the V/STOL model, the Andrea Doria would hold eight Harriers or 12 helicopters. Other navies with aircraft carriers, helicopter carriers, helicopter destroyers, or amphibious assault ships included Japan, Brazil, India, Spain, Thailand, and Peru.

Further Reading

Books

Clancy, Tom. Carrier: A Guided Tour of an Aircraft Carrier. New York: Berkley Books, 1999.

Kaufman, Yogi. City at Sea. Annapolis, MD: Naval Institute Press, 1995.

Musciano, Walter A. Warbirds of the Sea: A History of Aircraft Carriers and Carrier-Based Aircraft. Atglen, PA: Schiffer Publishing, 1994.

Polmar, Norman. The Naval Institute Guide to the Ships and Aircraft of the U.S. Fleet. Annapolis, MD: Naval Institute Press, 1993.

Preston, Anthony. Carriers. New York: Gallery Books, 1993.

Wooldridge, E. T. Carrier Warfare in the Pacific: An Oral History Collection. Washington, D.C.: Smithsonian Institution Press, 1993.

Electronic

Haze Gray and Underway World Aircraft Carrier Lists. <http://www.hazegray.org/navhist/carriers/> (April 13,2003).

U.S. Navy—The Aircraft Carriers. U.S. Navy Office of Information. <http://www.chinfo.navy.mil/navpalib/ships/carriers/> (April 13, 2003).

(DOD) A warship designed to support and operate aircraft, engage in attacks on targets afloat or ashore, and engage in sustained operations in support of other forces. Designated as CV or CVN. CVN is nuclear powered.

This article needs additional citations for verification. Please help improve this article by adding reliable references. Unsourced material may be challenged and removed. (April 2008)

From bottom to top: Principe de Asturias, amphibious assault ship USS Wasp, USS Forrestal and light V/STOL carrier HMS Invincible, showing size differences of late 20th century carriers

From foreground to background: HMS Illustrious, USS Harry S. Truman, and USS Dwight D. Eisenhower

An aircraft carrier is a warship designed with a primary mission of deploying and recovering aircraft, acting as a seagoing airbase. Aircraft carriers thus allow a naval force to project air power great distances without having to depend on local bases for staging aircraft operations. They have evolved from wooden vessels, used to deploy balloons, into nuclear powered warships that carry dozens of fixed and rotary wing aircraft.

Contents 1 Brief history 2 Types of aircraft carriers 2.1 By role 2.2 By configuration 3 Flight deck 4 Aircraft carriers in service 5 Future aircraft carriers 5.1 China 5.2 France 5.3 India 5.4 Italy 5.5 Russia 5.6 Spain 5.7 United Kingdom 5.8 United States 6 See also 6.1 Other aircraft carriers 6.2 Related lists 7 References 7.1 Notes 7.2 Bibliography 8 External links

Brief history

Main article: History of the aircraft carrier

The Japanese seaplane carrier Wakamiya conducted the world's first naval-launched air raids in September 1914.

Balloon carriers were the first ships to deploy manned aircraft, used during the 19th and early 20th century, mainly for observation purposes. The 1903 advent of fixed wing airplanes was followed in 1910 by the first flight of such an aircraft from the deck of a US Navy cruiser. Seaplanes and seaplane tender support ships, such as HMS Engadine, followed. The development of flat top vessels produced the first large fleet ships. This evolution was well underway by the mid 1920s, resulting in ships such as HMS Hermes, Hōshō, and the Lexington-class aircraft carriers.

World War II saw the first large-scale use and further refinement of the aircraft carrier, spawning several types. Escort aircraft carriers, such as USS Bogue, were built only during World War II. Although some were purpose-built, most were converted from merchant ships as a stop-gap measure to provide air support for convoys and amphibious invasions. Light aircraft carriers, such as USS Independence, represented a larger, more "militarized" version of the escort carrier concept. Although the light carriers usually carried the same size air groups as escort carriers, they had the advantage of higher speed as they had been converted from cruisers under construction.

Wartime emergencies also saw the creation or conversion of unconventional aircraft carriers. CAM ships, like SS Michael E, were cargo-carrying merchant ships which could launch but not retrieve fighter aircraft from a catapult. These vessels were an emergency measure during World War II as were Merchant aircraft carriers (MACs), such as MV Empire MacAlpine, another emergency measure which saw cargo-carrying merchant ships equipped with flight decks. Battlecarriers were created by the Imperial Japanese Navy to partially compensate for the loss of carrier strength at Midway.^{[citation needed]} Two of them were made from Ise-class battleships during late 1943. The aft turrets were removed and replaced with a hangar, deck and catapult. The heavy cruiser Mogami concurrently received a similar conversion. This "half and half" design was an unsuccessful compromise, being neither one thing nor the other. Submarine aircraft carriers, such as the French Surcouf and the Japanese I-400 class submarine, which was capable of carrying three Aichi M6A Seiran aircraft, were first built in the 1920s, but were generally unsuccessful at war.

The Tripoli, a US Navy Iwo Jima class helicopter carrier

Modern navies that operate such ships treat aircraft carriers as the capital ship of the fleet, a role previously played by the battleship. The change, part of the growth of air power as a significant factor in warfare, took place during World War II. This change was driven by the superior range, flexibility and effectiveness of carrier-launched aircraft. Following the war, carrier operations continued to increase in size and importance. Supercarriers, typically displacing 75,000 tonnes or greater, have become the pinnacle of carrier development. Most are powered by nuclear reactors and form the core of a fleet designed to operate far from home. Amphibious assault ships, such as USS Tarawa and HMS Ocean, serve the purpose of carrying and landing Marines, and operate a large contingent of helicopters for that purpose. Also known as "commando carriers" or "helicopter carriers", many have a secondary capability to operate VSTOL aircraft.

Lacking the firepower of other warships, carriers by themselves are considered vulnerable to attack by other ships, aircraft, submarines, or missiles. Therefore, aircraft carriers are generally accompanied by a number of other ships, to provide protection for the relatively unwieldy carrier, to carry supplies, and to provide additional offensive capabilities. This is often termed a battle group or carrier group, sometimes a carrier battle group.

Before World War II international naval treaties of 1922, 1930 and 1936 limited the size of capital ships including carriers. Aircraft carrier designs since World War II have been effectively unlimited by any consideration save budgetary, and the ships have increased in size to handle the larger aircraft. The large, modern Nimitz class of United States Navy carriers has a displacement nearly four times that of the World War II–era USS Enterprise, yet its complement of aircraft is roughly the same—a consequence of the steadily increasing size and weight of military aircraft over the years.

Types of aircraft carriers

This section requires expansion.

Brazilian aircraft carrier São Paulo (A12)

By role

• Anti-submarine warfare carrier
• Escort carrier
• Helicopter carrier
• Light aircraft carrier
• Amphibious assault ship

By configuration

There are three main configurations of aircraft carrier in service in the worlds navies:

• Catapult Assisted Take-Off But Arrested Recovery (CATOBAR)
• Short Take-Off But Arrested Recovery (STOBAR)
• Short Take-Off Vertical Landing (STOVL)

Flight deck

Main article: Flight deck

Ripples appear along the fuselage of a U.S. Navy E-2C Hawkeye due to loads from landing on the USS Harry S. Truman (CVN-75).

F/A-18 Hornets on the flight deck of the Nimitz-class supercarrier Harry S. Truman

The first carrier landing and take-off of a jet aircraft: Eric "Winkle" Brown landing on HMS Ocean (R68) in 1945

The ski-jump on Royal Navy carrier HMS Invincible (R05)

As "runways at sea," modern aircraft carriers have a flat-top deck design that serves as a flight deck for take-off and landing of aircraft. Aircraft take off to the front, into the wind, and land from the rear. Carriers steam at speed, for example up to 35 knots (65 km/h), into the wind during take-off in order to increase the apparent wind speed over the deck, thereby reducing the speed of the aircraft relative to the ship. On some ships, a steam-powered catapult is used to propel the aircraft forward, assisting the power of its engines and allowing it to take off in a shorter distance than would otherwise be required. On other carriers, aircraft do not require assistance for take off—the requirement for assistance relates to aircraft design and performance. Conversely, when landing on a carrier, conventional aircraft rely upon a tailhook that catches on arrestor wires stretched across the deck to bring them to a stop in a shorter distance than normal. Other aircraft—helicopters and V/STOL (Vertical/Short Take-Off and Landing) designs—utilize their hover capability to land vertically and so require no assistance in speed reduction upon landing.

Conventional ("tailhook") aircraft rely upon a landing signal officer (LSO, sometimes called "paddles") to control the plane's landing approach, visually gauge altitude, attitude, and speed, and transmit that data to the pilot. Before the angled deck emerged in the 1950s, LSOs used colored paddles to signal corrections to the pilot (hence the nickname). From the late 1950s onward, visual landing aids such as mirrors provided information on proper glide slope, but LSOs still transmit voice calls to landing pilots by radio.

To facilitate working on the flight deck of a U.S. aircraft carrier, the sailors wear colored shirts that designate their responsibilities. White shirts are responsible for safety, red shirts handle munitions, purple shirts (grapes) handle jet fuel, and green shirts handle the catapult and arresting gear. Yellow shirts are responsible for directing aircraft.

Key personnel involved in the flight deck include the Shooters, the Handler, and the Air Boss. Shooters are naval aviators or Naval Flight Officers and are responsible for launching aircraft. The Handler works just inside the island from the flight deck and is responsible for the movement of aircraft before launching and after landing. The Air Boss (usually a commander) occupies the top bridge (Primary Flight Control, also called "primary" or "the tower") and has the overall responsibility for controlling takeoffs, landings, "those aircraft in the air near the ship, and the movement of planes on the flight deck, which itself resembles a well-choreographed ballet".^[1] The captain of the ship spends most of his time one level below Primary on the Navigation Bridge. Below this is the Flag Bridge, designated for the embarked admiral and his staff.

Since the early 1950s it has been common to direct the landing recovery area off to port at an angle to the line of the ship. The primary function of the angled deck landing area is to allow aircraft that miss the arresting wires, referred to as a "bolter", to become airborne again without the risk of hitting aircraft parked on the forward parts of the deck. The angled deck also allows launching of aircraft at the same time as others land.

The above deck areas of the warship (such as the bridge, flight control tower) are concentrated to the starboard side of the deck in a relatively small area called an "island". Very few carriers have been designed or built without an island and such a configuration has not been seen in a fleet-sized carrier. The "flush deck" configuration proved to have very significant drawbacks, complicating navigation, air traffic control and numerous other factors.

A more recent configuration, originally developed by the Royal Navy but since adopted by many navies for smaller carriers, has a ski-jump ramp at the forward end of the flight deck. This was first developed to help launch VTOL (or STOVL) aircraft (aircraft that are able to take off and land with little or no forward movement), such as the Sea Harrier. Although these aircraft are capable of taking off vertically from the deck, using the ramp is more fuel efficient and permits a heavier launch weight. As catapults and arrestor cables are unnecessary, carriers with this arrangement reduce weight, complexity, and space needed for equipment. Russian and future Indian carriers include a ski-jump ramp for launching conventional aircraft. The disadvantage of the ski-jump—and the reason this configuration has not appeared on American supercarriers—is the penalty it exacts on aircraft size, payload, and fuel load (and thus range): large, slow planes such as the E-2 Hawkeye and heavily laden strike fighters like the F/A-18E/F Super Hornet and Sukhoi Su-33 cannot successfully launch using a ski-jump because their high loaded weight requires either a longer takeoff roll than is possible on a carrier deck, or catapult assistance, although the Su-33 does launch with a light fuel and weapons load from a ski jump.

Aircraft carriers in service

See also: List of aircraft carriers in service

HMS Invincible

Four modern aircraft carriers of various types—USS John C. Stennis, FS Charles de Gaulle, HMS Ocean and USS John F. Kennedy—and escort vessels on operations in 2002. The ships are sailing much closer together than they would during combat operations.

HTMS Chakri Naruebet and USS Kitty Hawk

Russian aircraft carrier Admiral Kuznetsov

Aircraft carriers are generally the largest ships operated by navies; a Nimitz-class carrier powered by two nuclear reactors and four steam turbines is 1,092 feet (333 m) long and costs about $4.5 billion. The United States Navy has the world's largest carrier fleet, with eleven in service and one under construction (all of them supercarriers). It is also the only navy to possess operational supercarriers. The U.S. Navy's aircraft carriers are a cornerstone of American power projection capability.

A total of 22 aircraft carriers in active service are maintained by nine navies. In addition, the People's Republic of China's People's Liberation Army Navy possesses the former Soviet aircraft carrier Varyag. The Netherlands, the United States, Brazil, South Korea, United Kingdom, the People's Republic of China, India, Japan, Australia, and France also operate vessels capable of carrying and operating multiple helicopters.

Classes currently in service:

Brazil (1)

• NAe São Paulo: 32,800-ton ex-French carrier FS Foch (launched 1960), purchased in 2000.

France (1)

• Charles de Gaulle (R 91): 42,000-ton nuclear-powered aircraft carrier, commissioned in 2001.

India (1)

• INS Viraat: 28,700-ton ex-British carrier HMS Hermes (launched 1953), purchased in 1986 and commissioned in 1987, scheduled to be decommissioned in 2019.^[2]

Italy (2)

• Giuseppe Garibaldi: 14,000-ton Italian STOVL carrier, commissioned in 1985.
• Cavour: 27,000-ton Italian STOVL carrier, commissioned in 2008.

Japan (1)

• Hyūga class: two helicopter destroyers (ASW carriers) planned, of which one is already in commission.

Russia (1)

• Admiral Flota Sovetskovo Soyuza Kuznetsov: 67,500-ton Kuznetsov-class STOBAR aircraft carrier. Launched in 1985 as Tbilisi, renamed and operational from 1995.

Spain (1)

• Principe de Asturias: 17,200-ton STOVL carrier, commissioned in 1988.

Thailand (1)

• HTMS Chakri Naruebet: 11,400-ton carrier based on Spanish Principe De Asturias design. Commissioned in 1997, though remains predominantly inactive due to lack of funds.^{[citation needed]}

United Kingdom (2)

• Invincible class: Three STOVL carriers were originally commissioned, of which two are in active service.

United States (11)

• USS Enterprise (CVN-65): 93,500-ton nuclear-powered supercarrier commissioned in 1961. First nuclear-powered aircraft carrier. Due for decommissioning in 2013.
• Nimitz class: ten 101,000-ton nuclear-powered supercarriers, the first of which was commissioned in 1975.

Future aircraft carriers

Several nations which currently possess aircraft carriers are in the process of planning new classes to replace current ones. The world's navies still generally see the aircraft carrier as the main future capital ship, with developments such as the arsenal ship, which have been promoted as an alternative, seen as too limited in terms of flexibility.

Military experts such as John Keegan^[3] have noted that in any future naval conflict between reasonably evenly matched powers, all surface ships—including aircraft carriers—would be at extreme and disproportionate risk, mainly due to the advanced capabilities of satellite reconnaissance and anti-ship missiles. Contrary to the thrust of most current naval spending, Keegan therefore postulates that eventually most navies will move to submarines as their main fighting ships, including in roles where submarines play only a minor or no role at the moment.

China

China bought the unfinished Soviet aircraft carrier Varyag in 2001 from Ukraine, supposedly to turn it into a floating casino. Pictures taken while in port suggest this plan has been abandoned and show that work is being carried out to maintain its military function. There is no conclusive evidence as to what role it would play in the Chinese Navy.

In late December 2008 and early January 2009, there were multiple reports of China building two conventionally powered aircraft carriers displacing 50,000–60,000 tonnes, possibly to be launched in 2015,^[4] and there have been press reports suggesting China's intention to build aircraft carriers.^[5]

France

The French Navy has set in motion possible plans for a second CTOL aircraft carrier, to supplement Charles de Gaulle. The design would be much larger, in the range of 65–74,000 tonnes, and would not be nuclear-powered like Charles de Gaulle. There are plans to base the carrier on the current Royal Navy design for CATOBAR operations. (The Thales/BAE Systems design for the Royal Navy is for a STOVL carrier which is reconfigurable to CATOBAR operations.)

On 21 June 2008, French President Nicolas Sarkozy decided to place France's participation in the project on hold. He stated that a final decision on the future of the French carrier would be taken in 2011 or 2012. British plans for two aircraft carriers will go ahead as planned and were in no way conditional on French participation.^[6]

India

Impression of the INS Vikramaditya, which is under refit for the Indian Navy.

India started the construction of a 40,000 tonne, 260 m-long Vikrant-class aircraft carrier in April 2005.^[7] The new carrier will cost US$762 million and will operate MiG-29K, Naval HAL Tejas and Sea Harrier aircraft along with the Indian-made helicopter HAL Dhruv.^[7] The ship will be powered by four turbine engines and will have a range of 8,000 nautical miles (14,000 km), carrying 160 officers, 1,400 sailors, and 30 aircraft. The carrier is being constructed by a state-run shipyard in Cochin.^[7] The ship is scheduled for commissioning in 2015.^[7]

India has indicated that at least two further carriers of the same or similar designs to INS Vikrant are planned.^[7] The first of these, to be named INS Viraat, is scheduled to begin construction in 2011 and be commissioned in 2017.^[7]

In 2004, India agreed to buy the Admiral Gorshkov from Russia for US$1.5 billion. It is most likely to be named INS Vikramaditya, and was expected to join the Indian Navy in 2008 after a refit.^[8] However, delays in the refit were announced in July 2007.

In July 2008, Russia increased the total price to US$3.4 billion because of unexpected cost overuns due to the deteriorated condition of the ship.^[9] In December 2008, India finally decided in favour of purchasing Admiral Gorshkov as the best option available.^[10] In February 2009, Russia asked for an additional $700 million payment for the completion of the reconstruction of the Admiral Gorshkov, bringing the total price requested by the Russians to $2.9 billion, more than three times the originally contracted price.^[11]

Italy

The Italian aircraft carrier Cavour

The construction of the conventionally powered Marina Militare STOVL aircraft carrier Cavour began in 2001. The ship of nearly 30,000 tons is being built by Fincantieri of Italy and has been officially commissioned to the Italian Navy since summer 2008. The ship can operate with AV-8B, F-35B, AW101, NH-90, and SH-3 Sea King. After some delay due to additional enlargements, Cavour is expected to be in full operational capability (FOC) in 2009 to complement the Marina Militare aircraft carrier Giuseppe Garibaldi. The ship is designed to combine fixed wing V/STOL and helicopter air operations with the transport of military or civil personnel and heavy vehicles.^[12]

Russia

Russian Navy Commander-in-Chief Admiral Vladimir Masorin officially stated on June 23, 2007, that the Navy was considering the specifications of a new nuclear aircraft carrier design^[13][14] for the class that was first announced about a month earlier. Production of the carriers is expected to start around 2010 at the Zvezdochka plant in Severodvinsk, where a large drydock, capable of launching vessels with more than 100,000 ton displacement, is now being built.^[15] In his statement, Admiral Masorin said that the general dimensions of the project have already been determined. The projected carrier is to have nuclear propulsion, to displace about 50,000 tons and to carry an air wing of 30–50 air superiority aircraft and helicopters, which makes her roughly comparable with the French Charles de Gaulle. "The giants that the US Navy builds, those that carry 100–130 aircraft, we won't build anything like that", said Admiral Masorin.^[14] The planned specifications reflect the role, traditional in the Russian Navy, of the aircraft carrier as an air support platform for guided missile cruisers and submarines.

The Russian naval establishment had long agreed, since the decommissioning of the Kiev-class carriers, that the only operational carrier, Admiral Kuznetsov, was insufficient, and that three or four carriers were necessary to meet the Navy's air support requirements.^{[citation needed]} However, financial and organisational turmoil in the 1990s made even the maintenance of Admiral Kuznetsov a difficult undertaking. The improvement in Russia's economic situation after the year 2000 has allowed a major increase in defence spending. Admiral Vladimir Vysotsky announced on Navy Day 2008 that Russia plans to build five or six carriers of the new design for deployment in the Northern and Pacific fleets, starting around 2012–2013.^[16] The new carrier groups are planned to be at full strength around 2050–2060.^[17] According to sources from the United Shipbuilding Corporation the new carriers will carry new fifth-generation fighters as well as unmanned aerial vehicles and have a displacement of up to 60,000 metric tons.^[18]

Spain

The 231 meter-long, 27,000 tonne Juan Carlos I for the Spanish Navy was approved in 2003, and its construction started in August 2005, with the shipbuilding firm Navantia in charge of the project.^[19] The ship was launched on 10 March 2008,^[19] and is due to be commissioned in 2011.^{[citation needed]} Juan Carlos I is designed to operate both as an amphibious assault ship and as STOVL aircraft carrier, depending on the mission assigned.^[19] The design was made keeping in mind the low-intensity conflicts in which the Spanish Navy is likely to be involved in the future. When configured for air operations the ship will displace 24,660 tonnes and will be able to carry a mixed force of up to 30 aircraft comprising AV-8B+ Matadors, F-35s and helicopters.^[19] The ship is provided with a ski-jump and a three-dimensional radar-based combat system.^[19]

United Kingdom

Impression of the Queen Elizabeth class, two of which are under construction for the Royal Navy.

The Royal Navy has signed a deal to build two new larger STOVL aircraft carriers, the Queen Elizabeth class, to replace the three Invincible-class carriers. The ships are to be named HMS Queen Elizabeth and HMS Prince of Wales.^[20][21] They will be able to operate up to 40 aircraft, and will have a displacement of around 65,000 tonnes. The two ships are due to enter service in 2014 and 2016 respectively. Their primary aircraft complement will be made up of F-35B Lightning IIs, and their ship's company will number around 600. The two ships will be the largest warships ever built for the Royal Navy. Initially to be configured for STOVL operations, the carriers are to be adaptable to STOBAR or CATOBAR configurations to allow any type of future generation of aircraft to operate from them.

United States

Artist's impression of the US Gerald R. Ford class aircraft carrier

The current US fleet of Nimitz-class carriers are to be followed into service (and in some cases replaced) by the Gerald R. Ford-class. It is expected that the ships will be larger than the Nimitz, and will also be designed to be less detectable by radar. The United States Navy is also looking to make these new carriers more automated in an effort to reduce the amount of funding required to maintain and operate its supercarriers. The main new features are implementation of EMALS (which replace the old steam catapults) and unmanned aerial vehicles. Each squadron of three UAVs would be controlled by one remote pilot.^{[citation needed]}

With the decommissioning of the USS John F. Kennedy in March 2007, the U.S. fleet has been reduced to 11 supercarriers; thus creating major discussions between the Joint Chiefs of Staff and Congress. The House Armed Services Seapower subcommittee on July 24, 2007, recommended seven or maybe eight new carriers (one every four years). However, the debate has deepened over budgeting for the $12–14.5 billion (plus $12 billion for development and research) for the 100,000-ton Gerald Ford-class carrier (estimated service 2015) compared to the smaller $2 billion 45,000-ton America-class amphibious assault ships able to deploy squadrons of F-35B.^[22]

See also

• History of the aircraft carrier
• Modern US Navy carrier air operations
• Project Habakkuk
• Seadrome
• Mobile offshore base
• Hull classification symbol
• Unsinkable aircraft carrier

Other aircraft carriers

• Anti-submarine warfare carrier
• Escort carrier
• Helicopter carrier
• Light aircraft carrier
• Supercarrier
• Amphibious assault ship
• Seaplane tender
• Balloon carrier
• Airborne aircraft carrier
• Submarine aircraft carrier
• Land mobile aircraft carrier

Related lists

• List of aircraft carriers
  • List of aircraft carriers by country
  • List of aircraft carriers by configuration
  • List of aircraft carrier classes of the United States Navy
  • List of aircraft carriers in service
  • Timeline for aircraft carrier service
• List of amphibious warfare ships

References

Notes

1. ^ "The US Navy Aircraft Carriers". Navy.mil. http://www.navy.mil/navydata/ships/carriers/powerhouse/powerhouse.asp. Retrieved 2009-01-30. 
2. ^ [1]
3. ^ Submarine aircraft carriers (uneven-quality private website, but has third-party citations in support)
4. ^ Herald Asahi, http://www.asahi.com/english/Herald-asahi/TKY200812310046.html 
5. ^ China Daily, http://www.chinadaily.com.cn/china/2009-03/23/content_7607571.htm 
6. ^ "President Sarkozy ditches Franco-British carrier project". Business.timesonline.co.uk. http://business.timesonline.co.uk/tol/business/industry_sectors/engineering/article4183255.ece. Retrieved 2009-01-30. 
7. ^ ^{a b c d e f} "Indian Aircraft Carrier (Project-71)". Indian Navy [Bharatiya Nau Sena]. Bharat Rakshak. http://www.bharat-rakshak.com/NAVY/Ships/Future/185-Indian-Aircraft-Carrier.html. Retrieved 11 September 2009. 
8. ^ "Article on India's indigenously built aircraft carrier". .chinadaily.com.cn. 2005-04-12. http://www2.chinadaily.com.cn/english/doc/2005-04/12/content_433517.htm. Retrieved 2009-01-30. 
9. ^ Russian aircraft carrier ready in 2012 if India pays $2 bln more
10. ^ [2]
11. ^ [3]
12. ^ "Cavour - Light multirole Aircraft Carrier". Digilander.libero.it. http://digilander.libero.it/en_mezzi_militari/html/en_cavour.html. Retrieved 2009-01-30. 
13. ^ "Russia to Build New Aircraft Carrier". http://kommersant.com/p-10807/r_500/aircraft_carrier/. Retrieved 2007-06-23. 
14. ^ ^{a b} Lenta. Ru newssiteGoogle translation – English 23 June 2007
15. ^ Lenta. Ru newssite Google translation – English 4 July 2006
16. ^ RIA Novosti. 2008, 27 July. "Russia to have 5-6 aircraft carriers in Northern, Pacific Fleets".
17. ^ RIA Novosti. 2008, 4 April. "Russia to have 5-6 aircraft carriers by 2060 - Navy commander".
18. ^ http://en.rian.ru/russia/20090227/120342249.html
19. ^ ^{a b c d e} "LHD Juan Carlos I". Armada Española official web site. http://www.armada.mde.es/ArmadaPortal/page/Portal/ArmadaEspannola/conocenos_modernizacion/02_jc_i--01_antecedentes_es. Retrieved 2009-02-24. 
20. ^ "Queen Elizabeth class Future Aircraft Carrier CVF (002)." Pike, J. GlobalSecurity.org.
21. ^ "UK | £3.2bn giant carrier deals signed". BBC News. 2008-07-03. http://news.bbc.co.uk/1/hi/uk/7486683.stm. Retrieved 2009-01-30. 
22. ^ Kreisher, Otto (October 2007). "Seven New Carriers (Maybe)". AIR FORCE MAGAZINE, Journal of the Air Force Association (Air Force Association) 90 (10): 68–71. ISSN 0730-6784. http://www.airforce-magazine.com/MagazineArchive/Pages/2007/October%202007/1007carriers.aspx. Retrieved 2007-10-02. 

Bibliography

• Francillon, René J, Tonkin Gulf Yacht Club US Carrier Operations off Vietnam, (1988) ISBN 0-87021-696-1
• Nordeen, Lon, Air Warfare in the Missile Age, (1985) ISBN 1-58834-083-X
• Ader, Clement, "Military Aviation", 1909, Edited and translated by Lee Kennett, Air University Press, Maxwell Air Force Base Alabama, 2003, ISBN 1-58566-118-X
• Friedman, Norman, U. S. Aircraft Carriers: an Illustrated Design History, Naval Institute Press, 1983 – ISBN 0870217399. Contains many detailed ship plans.
• Polak, Christian (2005) (in French, Japanese). Sabre et Pinceau: Par d'autres Français au Japon. 1872-1960. Hiroshi Ueki (植木 浩), Philippe Pons, foreword; 筆と刀・日本の中のもうひとつのフランス (1872-1960). éd. L'Harmattan. 
• Sturtivant, Ray (1990). British Naval Aviation, The Fleet Air Arm, 1917–1990. London: Arm & Armour Press. ISBN 0 85368 938 5. 

External links

Wikimedia Commons has media related to: Aircraft carriers

• World Wide Aircraft Carriers: Their specifications, history, and pictorial review
• Future Aircraft Carrier: UK – Armed Forces International
• Aircraft carriers of the USN
• Info about flight deck crew, arresting cables, catapults
• How Stuff Works – Aircraft Carriers
• Haze Gray & Underway, World Aircraft Carrier Lists comprehensive and detailed listings of all the world's aircraft carriers and seaplane tenders from 1913–2001, with photo gallery.
• Ships That Mother Seaplanes: craft of the "hush-hush" fleet may play a part in first trans-Atlantic flight. Popular Science monthly, February 1919, page 80, on Google Books.

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