Introduction to Aircraft Carrier
Aircraft Carrier, a naval vessel that uses airplanes and helicopters as its principal weapons. It is a ship used as a mobile base for the aircraft. The carrier is a floating air base that can go great distances to launch air attacks against enemy land or naval forces. It is the most powerful surface warship due to its aircraft striking force. It can be used for hit-and-run raids, sustained air offensives, antisubmarine warfare, and amphibious operations, and to provide aerial support for troops ashore. Oil tankers of the largest size are the only ships that are bigger than the carriers.
Carriers are the principal surface ships in the navies of the United States, the United Kingdom, and France. Russia has several carriers designed for helicopters and STOL (short takeoff and landing) planes. Some naval experts believe that nuclear-powered submarines carrying nuclear missiles may make carriers unnecessary in a major war. Some question the wisdom of building such large ships when they have become increasingly vulnerable as nations have armed their navies and air forces with guided missiles. However, the carrier is still valued for limited wars and peacekeeping missions.
Description
An aircraft carrier is readily recognized by its flight deck—the flat top deck from which planes are launched and on which they land. (The characteristic shape of carriers gave rise to the nickname “flattops.”) A large carrier usually has an angled, or canted, deck—a projection that juts out at an angle from the axial (fore-and-aft) flight deck. The canted deck is the landing area; the axial flight deck is used for launching and parking planes. Planes can be launched from a carrier with a canted deck at the same time that other planes are being landed. Conventional aircraft have modern carriers with angled landing sections on their flight decks, which take up the rear two-thirds of the deck, and angle toward the carrier's port side (left side facing forward), extending over the water. A plane sometimes makes a bad approach or misses the arresting wires with its tail hook; in this case, it may keep going and fly off the deck. Helicopters and V/STOL (Vertical/Short Take-Off and Landing) aircraft do not need a runway as their take off and landing is done vertically.
Heavy airplanes with high takeoff speeds are launched by steam-operated catapults that accelerate the planes to high speeds in seconds. Slower planes may be launched under their own power by short runs down the deck, the method used in World War II. Flight operations from carriers are carried out by conventional airplanes, helicopters, and V/STOL. Countries which have carriers that launch and land conventional aircraft include Brazil, France, Russia, and the United States. Other countries having carriers carry only V/STOL aircraft and helicopters. The conventional airplanes are launched by a catapult from take-off areas as they are too heavy. During take offs the carriers steam into the wind at high speed. The planes are lifted both by speed of the wind and the ship’s speed. When planes land, the carrier heads into the wind as well. The wind speed over the carrier's deck is 50 knots if the carrier steams at 25 knots (nautical miles per hour) into a wind blowing 25 knots. If a plane is flying at 100 knots, the relative landing speed is only of 50 knots.
Special techniques are needed to land a plane on a carrier. Not only is the landing area small, but it is also moving and, often, pitching as well. Relatively slow planes can be guided by an officer standing on deck using hand-held flags or lights as signals.
Jet planes are usually landed with the aid of a mirror system, in which a beam of light travels from the plane to a mirror on the carrier and back. The pilot guides the plane according to the location of the reflected beam. At the same time, a computer on the carrier determines the proper landing speed, and radio signals control the plane's throttle accordingly. As the plane touches down, a hook projecting from its tail catches on arresting gear, one of several arresting wires, cables stretched across the deck to bring the plane to a quick stop over a distance of around 300 feet (91 meters).
A carrier's island is a mass of superstructure at one side of the flight deck. It rises on the flight deck's starboard side (right side facing forward). The rest of the deck is left for planes. It comprises of the command and navigation bridges, communications equipment, radar antennas, and smokestacks unless the ship has nuclear power. It houses the bridge and flight-control center and is topped by radar and radio masts. Some carriers have been built without superstructure, notably the flush-deck carriers used by Japan in World War II.
Below the flight deck is the hangar deck, where planes are stored and serviced. Elevators transfer planes between the hangar deck and the flight deck. Repair shops are also on the hangar deck. Other than these, a carrier also has maintenance shops, living quarters and mess for the pilots, air crews, and ship’s crew. Additionally, it has separate storage space for bombs, ammunition, fuel, and food.
Carriers have antiaircraft guns and defensive missile launchers. The large flight deck, however, limits the number and placement of these weapons to such an extent that the carrier cannot adequately protect itself. For this reason carriers are generally used in strike forces (formerly called task forces), which include cruisers, destroyers, frigates, radar picket ships, and submarines. These protect the carriers from enemy missiles, planes, surface ships, and submarines. A fleet like this is known as a carrier task force or battle group. The U.S. navy with 11 ships has the largest carrier fleet. The navies of Brazil, France, India, Italy, Russia, Spain, Thailand, and the United Kingdom have at least one aircraft carrier each.
Types of Carriers
The United States, Russia, and France each have aircraft carriers that primarily carry fixed-wing planes, which are capable of attacking the enemy from great distances. They are the largest of all aircraft carriers, have long landing decks, and are used with other vessels in strike forces to project a nation's offensive power.
The navies of Great Britain, Spain, Italy, India, and Russia each have carriers that are equipped with both helicopters and V/STOL (vertical, short takeoff and landing) planes. They are used primarily in antisubmarine warfare and have limited strike capabilities.
The U.S. Navy designates its conventionally powered strike carriers as CV, and nuclear-powered carriers as CVN. The aircraft carriers are the most important warships for the U.S. Navy. They carry jet fighters and jet bombers. Additionally, they have radar, reconnaissance, and tanker planes, and antisubmarine aircraft. Six helicopters are usually carried by each carrier.
United States carriers are in two classes, corresponding to size. The name of each class of ships is the name of the first ship built in that class. The two classes are Nimitz and Enterprise, both of which are nuclear powered. The largest carriers in the world are in the Nimitz class, the first of which, the Nimitz, was completed in 1975. Each is about 1,092 feet (333 m) long with a flight deck of 252 feet (77 m) wide and displaces about 97,000 tons (loaded). Each carries about 85 planes and nearly 5,700 people. The Nimitz comprises of the Dwight D. Eisenhower, the Carl Vinson, the Theodore Roosevelt, the Abraham Lincoln, the George Washington, the John C. Stennis, the Harry S. Truman, the Ronald Reagan, and the George H. W. Bush. The Nimitz class ships are the largest ships in the world measured in displacement tonnage. This measurement indicates the number of long tons or metric tons of water displaced (occupied) by a ship.
The Enterprise class includes one ship, the Enterprise. This ship was commissioned in 1961. It was the first ever nuclear powered aircraft carrier in the world. When fully loaded it displaces 89,600 long tons (91,000 metric tons). It can carry 85 aircraft and around 5,800 people.
A third class, the Kitty Hawk Class, is no longer used. It was made up of one oil-powered ship, the Kitty Hawk. When fully loaded it displaced 80,800 long tons (82,100 metric tons) and carried 85 aircraft and about 5,600 people.
The United States has various carriers, called amphibious assault ships, used to deliver Marines into combat in amphibious assaults. The U.S. Navy's LHD and LHA amphibious assault ships carry both helicopters and V/STOL planes (which are used to attack enemy positions); the LPH carries only helicopters.
Carrier Planes
Carrier planes must have relatively low landing speeds and be capable of performing varied missions. Most types have folding wings to save space on the hangar deck.
Attack Planesseek out and destroy enemy targets both on land and at sea. These planes carry rockets, guided missiles, torpedoes, mines, and conventional or nuclear bombs. Attack planes have replaced the torpedo planes and dive bombers used by carriers in World War II.
Fighter Planesare generally lighter, faster, and more maneuverable than attack planes. Fighters intercept enemy planes, defend surface forces, escort attack planes, and may support ground troops. They are armed with fixed weapons, usually one or two pairs of 20-mm guns, and may carry missiles and other weapons.
Helicoptersare the primary aircraft used on the smaller carriers assigned to antisubmarine warfare and amphibious assault missions. Helicopters also are used on mine-sweeping missions and for general utility purposes, including rescue, transport, and reconnaissance duties. Large carriers may carry one or two helicopters.
Reconnaissance Planes,equipped with radar, infrared sensors, and cameras, are used for seeking out enemy vessels and planes. The reconnaissance planes also have ECM (electronic countermeasures) equipment to confuse enemy radar and targeting devices.
History
The first shipboard takeoff was made in 1910 by Eugene Ely, a civilian, in a Curtiss plane from the cruiser USS Birmingham. The same year British and American pilots began experimenting with take-offs and landings from ships. In 1911 Ely made a landing on an improvised flight deck on the battleship USS Pennsylvania. A catapult using compressed air for thrust successfully launched a seaplane from a barge in a 1913 test.
In 1913 the British navy built a launching platform for seaplanes on the cruiser Hermes. The Hermes was torpedoed and sunk in the early months of World War I. The British packet Engadine, equipped with a seaplane hangar, sent up an observation plane that spotted early German actions in the Battle of Jutland, 1916.
The Furious, a British Royal navy Cruiser was prepared with a flight deck in 1917. The Argus, converted by Britain from an Italian liner in 1918, is considered the first true aircraft carrier—previous British carriers could handle only seaplanes. A second Hermes, completed in 1924, was the first ship designed from the keel up as a carrier.
The U.S. Navy's first carrier was the flush-deck Langley, converted from a collier (coal supply ship) in 1922. Two battle cruisers laid down during World War I were completed in 1928 as the carriers Saratoga and Lexington. The Ranger, completed in 1934, was the first U.S. Navy ship originally planned as a carrier.
Japan was another pioneer in the use of carriers. Its first, the Hosho, was completed in 1922. At the beginning of World War II Japan had nine aircraft carriers—two more than the United States.
Six carriers formed the Japanese main striking force in the attack on Pearl Harbor, December 7, 1941. With its battleship fleet badly crippled by this attack, the U.S. Navy had to depend on carriers and submarines to fight the Japanese. The first carrier battle was the Battle of the Coral Sea, May 4–8, 1942, in which each side lost one carrier. In the decisive Battle of Midway, June 4–6, 1942, the Japanese lost four carriers, the U.S. Navy one.
U.S. Navy carriers spearheaded drives in the Central and South Pacific. The first United States air attack on Japan was made by bombers from Hornet. Japanese losses of planes and pilots were so severe that Japan withdrew its remaining carriers from the area. Early in 1943 new attack carriers began joining the American fleet; they were soon supplemented by large numbers of escort carriers.
Japan committed its naval air power again in the Battle of the Philippine Sea, June 19–21, 1944. Almost all of the Japanese carrier planes were shot down. In the Battle of Leyte Gulf, October 23–26, 1944, the Japanese fleet was eliminated as an effective fighting force. Four of its carriers were destroyed in this encounter. During the World War II (1939-1945) the nations involved in the war built more than 150 aircraft carriers. These were particularly important ships of the war. British aircraft carriers accompanied supply convoys in the Atlantic Ocean and the Mediterranean Sea, while taking part in fleet actions like sinking of the German battleship Bismarck. Post World War II many carriers were scrapped. By the mid 20th century the U.S. was the only country having a large fleet of carriers. Some of these ships included the ships of the Forrestal class namely, the Forrestal, the Saratoga, the Ranger, and the Independence. Commissioned in 1955, the Forrestal was the first U.S. carrier to have angled flight deck and to carry jet fighters. The Forrestal ships carried more aircraft and were sometimes called supercarriers.
In the Korean War (1950–53) British and American attack carriers were used, and escort carriers took part in many actions. Carrier strikes supported the Inchon landing and the evacuation of Hungnam.
During the Vietnamese War, the United States used carriers as bases for air strikes against the North Vietnamese, 1964–73.