Nimitz class aircraft carrier
Encyclopedia
The Nimitz-class supercarrier
Supercarrier
Supercarrier is an unofficial descriptive term for the largest type of aircraft carrier, usually displacing over 70,000 long tons.Supercarrier is an unofficial descriptive term for the largest type of aircraft carrier, usually displacing over 70,000 long tons.Supercarrier is an unofficial...

s are a class
Ship class
A ship class is a group of ships of a similar design. This is distinct from a ship-type, which might reflect a similarity of tonnage or intended use. For example, the is a nuclear aircraft carrier of the Nimitz class....

 of ten nuclear-powered aircraft carriers in service with the United States Navy
United States Navy
The United States Navy is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. The U.S. Navy is the largest in the world; its battle fleet tonnage is greater than that of the next 13 largest navies combined. The U.S...

. With an overall length of 1092 ft (332.8 m) and full-load displacements of over 100,000 long ton
Long ton
Long ton is the name for the unit called the "ton" in the avoirdupois or Imperial system of measurements, as used in the United Kingdom and several other Commonwealth countries. It has been mostly replaced by the tonne, and in the United States by the short ton...

s, they are the largest capital ship
Capital ship
The capital ships of a navy are its most important warships; they generally possess the heaviest firepower and armor and are traditionally much larger than other naval vessels...

s in the world. Instead of the gas turbines or diesel-electric systems used for propulsion on many modern warships, the carriers use two A4W
A4W reactor
The A4W reactor is a naval reactor used by the United States Navy to propel warships and generate onboard electricity.The A4W designation stands for:* A = Aircraft carrier platform* 4 = Fourth-generation core designed by the contractor...

 pressurized water reactor
Pressurized water reactor
Pressurized water reactors constitute a large majority of all western nuclear power plants and are one of three types of light water reactor , the other types being boiling water reactors and supercritical water reactors...

s which drive four propeller shafts and can produce a maximum speed of over 30 knots (58.8 km/h) and maximum power of around 260000 shp. As a result of the use of nuclear power, the ships are capable of operating for over 20 years without refueling and are predicted to have a service life of over 50 years. They are categorized as nuclear-powered aircraft carriers and are numbered with consecutive hull number
Hull number
Hull number is a serial identification number given to a boat or ship. A lower number implies an older vessel. The precise usage varies by country and type....

s between CVN-68 and CVN-77.The letters CVN denote the type of ship: "CV" is the hull classification symbol
Hull classification symbol
The United States Navy, United States Coast Guard, and United States National Oceanic and Atmospheric Administration use hull classification symbols to identify their ship types and each individual ship within each type...

 for aircraft carriers, and "N" indicates nuclear-powered propulsion. The number after the CVN means that this is the 68th "CV", or large aircraft carrier.


All ten carriers were constructed by Newport News Shipbuilding Company
Northrop Grumman Newport News
Newport News Shipbuilding , originally Newport News Shipbuilding and Drydock Company , was the largest privately-owned shipyard in the United States prior to being purchased by Northrop Grumman in 2001...

 in Virginia
Virginia
The Commonwealth of Virginia , is a U.S. state on the Atlantic Coast of the Southern United States. Virginia is nicknamed the "Old Dominion" and sometimes the "Mother of Presidents" after the eight U.S. presidents born there...

. , the lead ship
Lead ship
The lead ship or class leader is the first of a series or class of ships all constructed according to the same general design. The term is applicable military ships and larger civilian craft.-Overview:...

 of the class, was commissioned on 3 May 1975, and , the tenth and last of the class, was commissioned on 10 January 2009. Since the 1970s, Nimitz-class carriers have participated in many conflicts and operations across the world, including Operation Eagle Claw
Operation Eagle Claw
Operation Eagle Claw was an American military operation ordered by President Jimmy Carter to attempt to put an end to the Iran hostage crisis by rescuing 52 Americans held captive at the U.S. Embassy in Tehran, Iran on 24 April 1980...

 in Iran
Iran
Iran , officially the Islamic Republic of Iran , is a country in Southern and Western Asia. The name "Iran" has been in use natively since the Sassanian era and came into use internationally in 1935, before which the country was known to the Western world as Persia...

, the Gulf War
Gulf War
The Persian Gulf War , commonly referred to as simply the Gulf War, was a war waged by a U.N.-authorized coalition force from 34 nations led by the United States, against Iraq in response to Iraq's invasion and annexation of Kuwait.The war is also known under other names, such as the First Gulf...

, and more recently in Iraq and Afghanistan
War in Afghanistan (2001–present)
The War in Afghanistan began on October 7, 2001, as the armed forces of the United States of America, the United Kingdom, Australia, and the Afghan United Front launched Operation Enduring Freedom...

.

The angled flight deck
Flight deck
The flight deck of an aircraft carrier is the surface from which its aircraft take off and land, essentially a miniature airfield at sea. On smaller naval ships which do not have aviation as a primary mission, the landing area for helicopters and other VTOL aircraft is also referred to as the...

s of the carriers use a CATOBAR
CATOBAR
CATOBAR is a system used for the launch and recovery of aircraft from the deck of an aircraft carrier...

 arrangement to operate aircraft, with steam catapult
Aircraft catapult
An aircraft catapult is a device used to launch aircraft from ships—in particular aircraft carriers—as a form of assisted take off. It consists of a track built into the flight deck, below which is a large piston or shuttle that is attached through the track to the nose gear of the aircraft, or in...

s and arrestor wire
Arresting gear
Arresting gear, or arrestor gear, is the name used for mechanical systems designed to rapidly decelerate an aircraft as it lands. Arresting gear on aircraft carriers is an essential component of naval aviation, and it is most commonly used on CATOBAR and STOBAR aircraft carriers. Similar systems...

s for launch and recovery. As well as speeding up flight deck operations, this allows for a much wider variety of aircraft than with the STOVL
STOVL
STOVL is an acronym for short take off and vertical landing.This is the ability of some aircraft to take off from a short runway or take off vertically if it does not have a very heavy payload and land vertically...

 arrangement used on smaller carriers. An embarked carrier air wing
Carrier air wing
A Carrier Air Wing is an operational naval aviation organization composed of several aircraft squadrons and detachments of various types of fixed wing and rotary wing aircraft...

 consisting of up to around 90 aircraft is normally deployed on board. The air wings' strike fighter
Strike fighter
In a current military parlance, a strike fighter is a multi-role combat aircraft designed to operate primarily in the air-to-surface attack role while also incorporating certain performance characteristics of a fighter aircraft. As a category, it is distinct from fighter-bombers...

s are primarily F/A-18E/F Super Hornets and F/A-18C Hornets, after the retirement of the F-14 Tomcat. In addition to their aircraft, the vessels carry short-range defensive weaponry for anti-aircraft warfare
Anti-aircraft warfare
NATO defines air defence as "all measures designed to nullify or reduce the effectiveness of hostile air action." They include ground and air based weapon systems, associated sensor systems, command and control arrangements and passive measures. It may be to protect naval, ground and air forces...

 and missile defense.

Description

The Nimitz class carriers have an overall length of 1092 ft (332.8 m) and a full-load displacement of about 100,000–104,000 long ton
Long ton
Long ton is the name for the unit called the "ton" in the avoirdupois or Imperial system of measurements, as used in the United Kingdom and several other Commonwealth countries. It has been mostly replaced by the tonne, and in the United States by the short ton...

s (102,000–106,000 metric ton
Tonne
The tonne, known as the metric ton in the US , often put pleonastically as "metric tonne" to avoid confusion with ton, is a metric system unit of mass equal to 1000 kilograms. The tonne is not an International System of Units unit, but is accepted for use with the SI...

s). They have a beam at the waterline of 135 ft (41.1 m), and the maximum width of their flight decks is 251 ft 10 in to 257 ft 3 in (77.76 m to 78.41 m) (depending on the variant). The ships' companies can number up to 3,200, not including an air wing of 2,480.

Design

The Nimitz-class aircraft carriers were ordered to supplement the aircraft carriers of the Kitty Hawk class
Kitty Hawk class aircraft carrier
The Kitty Hawk-class supercarriers of the United States Navy were an incremental improvement on the Forrestal-class vessels. Four were built, all in the 1960s, , , and...

 and Enterprise class
USS Enterprise (CVN-65)
USS Enterprise , formerly CVA-65, is the world's first nuclear-powered aircraft carrier and the eighth US naval vessel to bear the name. Like her predecessor of World War II fame, she is nicknamed the "Big E". At , she is the longest naval vessel in the world...

, maintaining the strength and capability of the U.S. Navy after the older carriers were decommissioned. The ships were designed to be improvements on previous U.S. aircraft carriers, in particular the Enterprise and Forrestal-class
Forrestal class aircraft carrier
The Forrestal-class aircraft carriers were a four-ship class designed and built for the United States Navy in the 1950s. It was the first class of so-called supercarriers, combining high tonnage, deck-edge elevators and an angled deck...

 supercarriers, although the arrangement of the ships is relatively similar to that of the Kitty Hawk class. Among other design improvements, the two reactors on Nimitz class carriers take up less space than the eight reactors used on Enterprise. Along with a more generally improved design, this means that Nimitz-class carriers can carry 90% more aviation fuel and 50% more ordnance when compared to the Forrestal class.

The U.S. Navy has stated that the carriers could withstand three times the damage sustained by the Essex class
Essex class aircraft carrier
The Essex class was a class of aircraft carriers of the United States Navy, which constituted the 20th century's most numerous class of capital ships with 24 vessels built in both "short-hull" and "long-hull" versions. Thirty-two were originally ordered; however as World War II wound down, six were...

 inflicted by Japanese air attacks during World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...

. The hangars on the ships are divided into three fire bays by thick steel doors that are designed to restrict the spread of fire. This addition has been present on U.S. aircraft carriers since World War II, after the fires caused by Kamikaze
Kamikaze
The were suicide attacks by military aviators from the Empire of Japan against Allied naval vessels in the closing stages of the Pacific campaign of World War II, designed to destroy as many warships as possible....

 attacks.

The first ships were designed around the time of the Vietnam War
Vietnam War
The Vietnam War was a Cold War-era military conflict that occurred in Vietnam, Laos, and Cambodia from 1 November 1955 to the fall of Saigon on 30 April 1975. This war followed the First Indochina War and was fought between North Vietnam, supported by its communist allies, and the government of...

, and certain aspects of the design were influenced by operations there. To a certain extent, the carrier operations in Vietnam demonstrated the need for increased capabilities of aircraft carriers over their survivability, as they were used to send sorties into the war and were therefore less subject to attack. As a result of this experience, Nimitz carriers were designed with larger stores of aviation fuel and larger magazines in relation to previous carriers, although this was partly as a result of increased space available by the new design of the ships' propulsion systems.

A major purpose of the ships was initially to support the U.S. military during the Cold War
Cold War
The Cold War was the continuing state from roughly 1946 to 1991 of political conflict, military tension, proxy wars, and economic competition between the Communist World—primarily the Soviet Union and its satellite states and allies—and the powers of the Western world, primarily the United States...

, and they were designed with capabilities for that role, including using nuclear power instead of oil for greater endurance when deployed in blue water
Blue-water navy
The term blue-water navy is a colloquialism used to describe a maritime force capable of operating across the deep waters of open oceans. While what actually constitutes such a force remains undefined, there is a requirement for the ability to exercise sea control at wide ranges...

, and the ability to make adjustments to the carriers' weapons systems on the basis of new intelligence and technological developments. They were initially categorized only as attack carriers, but ships have been constructed with anti-submarine capabilities
Anti-submarine warfare
Anti-submarine warfare is a branch of naval warfare that uses surface warships, aircraft, or other submarines to find, track and deter, damage or destroy enemy submarines....

 since . As a result, the ships and their aircraft are now able to participate in a wide range of operations, which can include sea and air blockades, mine laying, and missile strikes on land, air and sea.

Because of a design flaw, ships of this class have inherent lists to starboard when under combat loads that exceed the capability of their list control systems. The problem appears to be especially prevalent on some of the more modern vessels. This problem has been previously rectified by using damage control voids for ballast, but a solution using solid ballast which does not affect the ship's survivability has been proposed.

Construction

All ten Nimitz-class aircraft carriers were constructed between 1968 and 2006 at Newport News Shipbuilding Company
Northrop Grumman Newport News
Newport News Shipbuilding , originally Newport News Shipbuilding and Drydock Company , was the largest privately-owned shipyard in the United States prior to being purchased by Northrop Grumman in 2001...

, in Newport News, Virginia
Newport News, Virginia
Newport News is an independent city located in the Hampton Roads metropolitan area of Virginia. It is at the southeastern end of the Virginia Peninsula, on the north shore of the James River extending southeast from Skiffe's Creek along many miles of waterfront to the river's mouth at Newport News...

, in the largest drydock in the western hemisphere, dry dock 12, now 2172 feet (662 m) long after a recent expansion.

Since , the carriers were manufactured in modular construction (USS George H.W. Bush was constructed from 161 'super-lift' modules). This means that whole sections could be welded together with plumbing and electrical equipment already fitted, improving efficiency. Using gantry cranes, the modules were lifted into the dry dock and welded. In the case of the bow section, these can weigh over 1500000 pound. This method was originally developed by Ingalls Shipbuilding
Ingalls Shipbuilding
Ingalls Shipbuilding is a shipyard located in Pascagoula, Mississippi, USA, originally established in 1938, and is now part of Huntington Ingalls Industries...

 and increases the rate of work because much of the fitting out does not have to be carried out within the confines of the already finished hull.

The total cost of construction for each ship was around $4.5 billion.All monetary values are adjusted for inflation to 2000s figures

Propulsion

All ships of the class are powered by two A4W nuclear reactor
A4W reactor
The A4W reactor is a naval reactor used by the United States Navy to propel warships and generate onboard electricity.The A4W designation stands for:* A = Aircraft carrier platform* 4 = Fourth-generation core designed by the contractor...

s, kept in separate compartments. They power four propeller shafts and can produce a maximum speed of over 30 knots (58.8 km/h) and maximum power of 260000 bhp. The reactors produce heat through nuclear fission
Nuclear fission
In nuclear physics and nuclear chemistry, nuclear fission is a nuclear reaction in which the nucleus of an atom splits into smaller parts , often producing free neutrons and photons , and releasing a tremendous amount of energy...

 which heats water. This is then passed through four turbines (manufactured by General Electric
General Electric
General Electric Company , or GE, is an American multinational conglomerate corporation incorporated in Schenectady, New York and headquartered in Fairfield, Connecticut, United States...

) which are shared by the two reactors. The turbines power the four bronze
Bronze
Bronze is a metal alloy consisting primarily of copper, usually with tin as the main additive. It is hard and brittle, and it was particularly significant in antiquity, so much so that the Bronze Age was named after the metal...

 propellers, each with a diameter of 25 feet (7.6 m) and a weight of 66000 pounds (29.9 MT). Behind these are the two rudders which are 29 feet (8.8 m) high and 22 feet (6.7 m) long, and each weigh 110000 pounds (49.9 MT). The Nimitz-class ships constructed since also have bulbous bow
Bulbous bow
A bulbous bow is a protruding bulb at the bow of a ship just below the waterline. The bulb modifies the way the water flows around the hull, reducing drag and thus increasing speed, range, fuel efficiency, and stability...

s in order to improve speed and fuel efficiency by reducing hydrodynamic drag. As a result of the use of nuclear power, the ships are capable of operating continuously for over 20 years without refueling and are predicted to have a service life of over 50 years.

Armament and protection

In addition to the aircraft carried onboard, the ships carry defensive equipment for direct use against missiles and hostile aircraft. These consist of either three or four NATO RIM-7 Sea Sparrow
RIM-7 Sea Sparrow
RIM-7 Sea Sparrow is a US ship-borne short-range anti-aircraft and anti-missile weapon system, primarily intended for defense against anti-ship missiles...

 missile launchers designed for defense against aircraft and anti-ship missile
Anti-ship missile
Anti-ship missiles are guided missiles that are designed for use against ships and large boats. Most anti-ship missiles are of the sea-skimming type, many use a combination of inertial guidance and radar homing...

s as well as either three or four 20 mm Phalanx CIWS
Phalanx CIWS
The Phalanx CIWS is an anti-ship missile defense system. It is a close-in weapon system and was designed and manufactured by the General Dynamics Corporation, Pomona Division...

 missile defense cannon. has none of these, having been built with the RIM-116 Rolling Airframe Missile
RIM-116 Rolling Airframe Missile
The RIM-116 Rolling Airframe Missile is a small, lightweight, infrared homing surface-to-air missile in use by the American, German, South Korean, Greek, Turkish, Saudi and Egyptian navies. It was intended originally and used primarily as a point-defense weapon against anti-ship cruise missiles...

 system, two of which have also been installed on and . These will be installed on the other ships as they return for Refueling Complex Overhaul (RCOH). Since USS Theodore Roosevelt, the carriers have been constructed with 2.5 in (63.5 mm) Kevlar
Kevlar
Kevlar is the registered trademark for a para-aramid synthetic fiber, related to other aramids such as Nomex and Technora. Developed at DuPont in 1965, this high strength material was first commercially used in the early 1970s as a replacement for steel in racing tires...

 armor over vital spaces, and earlier ships have been retrofitted with it: Nimitz in 1983–1984, Eisenhower from 1985–1987 and Vinson in 1989.

The other countermeasures the ships use are four Sippican SRBOC (super rapid bloom off-board chaff) six-barrel MK36 decoy launchers, which deploy infrared flares and chaff to disrupt the sensors of incoming missiles; an SSTDS torpedo defense system; and an AN/SLQ-25 Nixie
AN/SLQ-25 Nixie
The AN/SLQ-25 Nixie and its variants are towed torpedo decoys used on US and allied warships. It consists of a towed decoy device and a shipboard signal generator...

 torpedo countermeasures system. The carriers also use Raytheon AN/SLQ-32(V) electronic warfare
Electronic warfare
Electronic warfare refers to any action involving the use of the electromagnetic spectrum or directed energy to control the spectrum, attack an enemy, or impede enemy assaults via the spectrum. The purpose of electronic warfare is to deny the opponent the advantage of, and ensure friendly...

 systems to detect and disrupt hostile radar signals in addition to the electronic warfare capabilities of some of the aircraft on board.

The presence of nuclear weapons on board U.S. aircraft carriers since the end of the Cold War has neither been confirmed nor denied by the U.S. government. As a result of this, as well as concerns over the safety of nuclear power, the presence of a U.S. aircraft carrier in a foreign port has occasionally provoked protest from local people, for example when USS Nimitz docked in Chennai
Chennai
Chennai , formerly known as Madras or Madarasapatinam , is the capital city of the Indian state of Tamil Nadu, located on the Coromandel Coast off the Bay of Bengal. Chennai is the fourth most populous metropolitan area and the sixth most populous city in India...

, India
India
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...

, in 2007. At that time, the Strike Group commander Rear Admiral
Rear admiral (United States)
Rear admiral is a naval commissioned officer rank above that of a commodore and captain, and below that of a vice admiral. The uniformed services of the United States are unique in having two grades of rear admirals.- Rear admiral :...

 John Terence Blake stated that: "The U.S. policy is that we do not routinely deploy nuclear weapons on board Nimitz."

Carrier air wing

In order for a carrier to deploy, it must embark one of ten Carrier Air Wings (CVW).Although there are ten carrier air wings in the U.S. Navy, they are numbered between CVW-1 (USS Enterprise) and CVW-17 (USS Carl Vinson) The carriers can accommodate a maximum of 130 F/A-18 Hornets or 85–90 aircraft of different types, but current numbers are typically 64 aircraft. Although the air wings are integrated with the operation of the carriers they are deployed to, they are nevertheless regarded as a separate entity. As well as the aircrew, the air wings are also made up of support personnel involved in roles including maintenance, aircraft and ordnance handling and emergency procedures. Each person on the flight deck wears color-coded clothing to make their role easily identifiable.

A typical carrier air wing can include 12–14 F/A-18F Super Hornet
F/A-18E/F Super Hornet
The Boeing F/A-18E/F Super Hornet is a twin-engine carrier-based multirole fighter aircraft. The F/A-18E single-seat variant and F/A-18F tandem-seat variant are larger and more advanced derivatives of the F/A-18C and D Hornet. The Super Hornet has an internal 20 mm gun and can carry air-to-air...

s as strike fighters; two squadrons of 10–12 F/A-18C Hornets
F/A-18 Hornet
The McDonnell Douglas F/A-18 Hornet is a supersonic, all-weather carrier-capable multirole fighter jet, designed to dogfight and attack ground targets . Designed by McDonnell Douglas and Northrop, the F/A-18 was derived from the latter's YF-17 in the 1970s for use by the United States Navy and...

, with one of these often provided by the U.S. Marine Corps
United States Marine Corps
The United States Marine Corps is a branch of the United States Armed Forces responsible for providing power projection from the sea, using the mobility of the United States Navy to deliver combined-arms task forces rapidly. It is one of seven uniformed services of the United States...

 (VMFA), also as strike fighters; 4–6 EA-6B Prowlers
EA-6 Prowler
The Northrop Grumman EA-6B Prowler is a twin-engine, mid-wing electronic warfare aircraft modified from the basic A-6 Intruder airframe. The EA-6B has been in service with the U.S...

 for electronic warfare
Electronic warfare
Electronic warfare refers to any action involving the use of the electromagnetic spectrum or directed energy to control the spectrum, attack an enemy, or impede enemy assaults via the spectrum. The purpose of electronic warfare is to deny the opponent the advantage of, and ensure friendly...

; 4–6 E-2C Hawkeyes
E-2 Hawkeye
The Grumman E-2 Hawkeye is an American all-weather, aircraft carrier-capable tactical airborne early warning aircraft. This twin-turboprop aircraft was designed and developed during the late 1950s and early 1960s by the Grumman Aircraft Company for the United States Navy as a replacement for the...

 used for airborne early warning; C-2 Greyhounds used for logistics; and a Helicopter Antisubmarine Squadron of 6–8 SH-60F & HH-60H Seahawks
SH-60 Seahawk
The Sikorsky SH-60/MH-60 Seahawk is a twin turboshaft engine, multi-mission United States Navy helicopter based on the United States Army UH-60 Black Hawk and a member of the Sikorsky S-70 family. The most significant airframe modification is a hinged tail to reduce its footprint aboard ships.The...

. Aircraft that have previously operated from Nimitz-class carriers include F-14 Tomcat
F-14 Tomcat
The Grumman F-14 Tomcat is a supersonic, twin-engine, two-seat, variable-sweep wing fighter aircraft. The Tomcat was developed for the United States Navy's Naval Fighter Experimental program following the collapse of the F-111B project...

s, S-3 Viking
S-3 Viking
The Lockheed S-3 Viking is a four-seat twin-engine jet aircraft that was used by the U.S. Navy to identify, track, and destroy enemy submarines. In the late 1990s, the S-3B's mission focus shifted to surface warfare and aerial refueling. The Viking also provided electronic warfare and surface...

s, A-7 Corsair II
A-7 Corsair II
The Ling-Temco-Vought A-7 Corsair II is a carrier-based subsonic light attack aircraft introduced to replace the United States Navy's Douglas A-4 Skyhawk, initially entering service during the Vietnam War...

 and A-6E Intruder aircraft.

Flight deck and aircraft facilities

The flight deck
Flight deck
The flight deck of an aircraft carrier is the surface from which its aircraft take off and land, essentially a miniature airfield at sea. On smaller naval ships which do not have aviation as a primary mission, the landing area for helicopters and other VTOL aircraft is also referred to as the...

 is angled at nine degrees, which allows for aircraft to be launched and recovered simultaneously. This angle of the flight deck was reduced slightly in relation to previous carriers, as the current design improves the air flow around the carrier. Four steam catapults
Aircraft catapult
An aircraft catapult is a device used to launch aircraft from ships—in particular aircraft carriers—as a form of assisted take off. It consists of a track built into the flight deck, below which is a large piston or shuttle that is attached through the track to the nose gear of the aircraft, or in...

 are used to launch fixed-wing aircraft, and four arrestor wires are used for recovery. The two newest carriers, Reagan and Bush, only have three arrestor wires each, as the fourth was used infrequently on earlier ships and was therefore deemed unnecessary. This CATOBAR
CATOBAR
CATOBAR is a system used for the launch and recovery of aircraft from the deck of an aircraft carrier...

 arrangement allows for faster launching and recovery as well as a much wider range of aircraft that can be used on board compared with smaller aircraft carriers, most of which use a simpler STOVL
STOVL
STOVL is an acronym for short take off and vertical landing.This is the ability of some aircraft to take off from a short runway or take off vertically if it does not have a very heavy payload and land vertically...

 arrangement without catapults or arrestor wires. The ship's aircraft operations are controlled by the air boss on the bridge. Four large elevators transport aircraft between the flight deck and the hangars below. These hangars are divided into three bays by thick steel doors that are designed to restrict the spread of fire.

Strike groups

When an aircraft carrier deploys, it takes a Strike Group, made up of several other warships and supply vessels which allow the operation to be carried out. The armament of the Nimitz class is made up only of short range defensive weapons, used as a last line of defense against enemy missiles and aircraft. The other vessels in the Strike Group provide additional capabilities, such as long range Tomahawk
BGM-109 Tomahawk
The Tomahawk is a long-range, all-weather, subsonic cruise missile. Introduced by General Dynamics in the 1970s, it was designed as a medium- to long-range, low-altitude missile that could be launched from a surface platform. It has been improved several times and, by way of corporate divestitures...

 missiles or the Aegis Combat System
Aegis combat system
The Aegis Combat System is an integrated naval weapons system developed by the Missile and Surface Radar Division of RCA, and now produced by Lockheed Martin...

, and also protect the carrier from attack. A typical Strike Group may include, in addition to an aircraft carrier: up to six surface combatant
Surface combatant
Surface combatants are a subset of Naval Warships which are designed to engage in combat on the surface of the water, with their own weapons. They are generally ships built to fight other ships, submarines or aircraft, and can carry out several other missions including counter-narcotics operations...

s, including frigate
Frigate
A frigate is any of several types of warship, the term having been used for ships of various sizes and roles over the last few centuries.In the 17th century, the term was used for any warship built for speed and maneuverability, the description often used being "frigate-built"...

s, guided missile cruisers and guided missile destroyer
Guided missile destroyer
A guided missile destroyer is a destroyer designed to launch guided missiles. Many are also equipped to carry out anti-submarine, anti-air, and anti-surface operations. In the U.S...

s (used primarily for anti-aircraft warfare
Anti-aircraft warfare
NATO defines air defence as "all measures designed to nullify or reduce the effectiveness of hostile air action." They include ground and air based weapon systems, associated sensor systems, command and control arrangements and passive measures. It may be to protect naval, ground and air forces...

 and anti-submarine warfare
Anti-submarine warfare
Anti-submarine warfare is a branch of naval warfare that uses surface warships, aircraft, or other submarines to find, track and deter, damage or destroy enemy submarines....

); one or two attack submarines (for seeking out and destroying hostile surface ships and submarines); and an ammunition, oiler, and supply ship of Military Sealift Command
Military Sealift Command
The Military Sealift Command is a United States Navy organization that controls most of the replenishment and military transport ships of the Navy. It first came into existence on 9 July 1949 when the Military Sea Transportation Service became solely responsible for the Department of Defense's...

 to provide logistical support. The precise structure and numbers of each type of ship can vary between groups depending on the objectives of the deployment.

Design differences within the class

While the designs of the final seven ships (from ) are slightly different from those of the earlier ships, the U.S. Navy nevertheless regards all vessels as a single class. As the older carriers come in for Refueling and Complex Overhaul (RCOH), their nuclear power plants are refueled and they are upgraded to the standards of the latest ships. This is the most substantial overhaul the ships receive, although other refits may be performed to update the ships' equipment. The ships were initially categorized only as attack carriers but have been constructed with anti-submarine capabilities
Anti-submarine warfare
Anti-submarine warfare is a branch of naval warfare that uses surface warships, aircraft, or other submarines to find, track and deter, damage or destroy enemy submarines....

 since USS Carl Vinson. These improvements include better radar systems and facilities which enable the ships to operate aircraft in a more effective anti-submarine role, including the fitting of common undersea picture (CUP) technology which uses sonar
Sonar
Sonar is a technique that uses sound propagation to navigate, communicate with or detect other vessels...

 to allow for better assessment of the threat from submarines.

USS Theodore Roosevelt and those completed after her have slight structural differences from the earlier carriers such as improved protection for ordnance storage in their magazines
Magazine (artillery)
Magazine is the name for an item or place within which ammunition is stored. It is taken from the Arabic word "makahazin" meaning "warehouse".-Ammunition storage areas:...

. Other improvements include upgraded flight deck ballistic protection, first implemented on USS George Washington, and the high-strength low-alloy steel (HSLA-100) used for constructing ships since USS John C. Stennis. More recently, older ships have had their flight decks refitted with a non-slip material fitted on new-build ships, to improve safety for both crew and aircraft.

The final ship USS George H.W. Bush was designed as a "transition ship" to the Nimitz class replacement, the Gerald R. Ford class. Bush incorporates new technologies including improved propeller and bulbous bow
Bulbous bow
A bulbous bow is a protruding bulb at the bow of a ship just below the waterline. The bulb modifies the way the water flows around the hull, reducing drag and thus increasing speed, range, fuel efficiency, and stability...

 designs, a reduced radar signature and electronic and environmental upgrades. As a result, the ship's cost was US$6.2 billion, higher than that of the earlier Nimitz-class ships which each cost around US$4.5 billion. To lower costs, some new technologies and design features were also incorporated into the , the previous carrier, including a redesigned island.

Ships in class

The United States Navy lists the following ships in the Nimitz class:
Ship Hull Number Laid down Launched Commissioned RCOH Homeport (2010) References
CVN-68 22 June 1968 13 May 1972 3 May 1975 1998–2001 Naval Air Station North Island
Naval Air Station North Island
Naval Air Station North Island or NAS North Island is located at the north end of the Coronado peninsula on San Diego Bay and is the home port of several aircraft carriers of the United States Navy...

, San Diego, California
San Diego, California
San Diego is the eighth-largest city in the United States and second-largest city in California. The city is located on the coast of the Pacific Ocean in Southern California, immediately adjacent to the Mexican border. The birthplace of California, San Diego is known for its mild year-round...


Naval Station Everett
Naval Station Everett
Naval Station Everett is the United States Navy's most modern facility. It is located next to the marina area of the city of Everett, WA, 25 miles north of Seattle. The Navy Support Complex is located between Marysville and Arlington, 11 miles north of the naval station. Naval Station , Everett is...

, Everett, Washington
Everett, Washington
Everett is the county seat of and the largest city in Snohomish County, Washington, United States. Named for Everett Colby, son of founder Charles L. Colby, it lies north of Seattle. The city had a total population of 103,019 at the 2010 census, making it the 6th largest in the state and...

 (2011)
CVN-69 15 August 1970 11 October 1975 18 October 1977 2001–2005 Naval Station Norfolk
Naval Station Norfolk
Naval Station Norfolk, in Norfolk, Virginia, is a base of the United States Navy, supporting naval forces in the United States Fleet Forces Command, those operating in the Atlantic Ocean, Mediterranean Sea, and Indian Ocean...

, Norfolk, Virginia
Norfolk, Virginia
Norfolk is an independent city in the Commonwealth of Virginia in the United States. With a population of 242,803 as of the 2010 Census, it is Virginia's second-largest city behind neighboring Virginia Beach....

CVN-70 11 October 1975 15 March 1980 13 March 1982 2005–2009 Naval Air Station North Island, San Diego, California
CVN-71 31 October 1981 27 October 1984 25 October 1986 2009– Naval Station Norfolk, Norfolk, Virginia
CVN-72 3 November 1984 13 February 1988 11 November 1989 Naval Station Everett, Everett, Washington
Naval Station Norfolk, Norfolk, Virginia (2011)
CVN-73 25 August 1986 21 July 1990 4 July 1992 Yokosuka Naval Base
United States Fleet Activities Yokosuka
U.S. Fleet Activities Yokosuka, or Commander, Fleet Activities Yokosuka is a United States Navy base, in Yokosuka, Japan. Its mission is to maintain and operate base facilities for the logistic, recreational, administrative support and service of the U.S. Naval Forces Japan, U.S. 7th Fleet and...

, Yokosuka, Japan
CVN-74 13 March 1991 11 November 1993 9 December 1995 Naval Base Kitsap
Naval Base Kitsap
Naval Base Kitsap is a U.S. Navy base located on the Kitsap Peninsula in Washington state. It was created in 2004 by merging the former Naval Station Bremerton with Naval Submarine Base Bangor...

, Bremerton, Washington
Bremerton, Washington
Bremerton is a city in Kitsap County, Washington, United States. The population was 38,790 at the 2011 State Estimate, making it the largest city on the Olympic Peninsula. Bremerton is home to Puget Sound Naval Shipyard and the Bremerton Annex of Naval Base Kitsap...

CVN-75 29 November 1993 7 September 1996 25 July 1998 Naval Station Norfolk, Norfolk, Virginia
CVN-76 12 February 1998 4 March 2001 12 July 2003 Naval Base Kitsap, Bremerton, Washington (2011)
CVN-77 6 September 2003 9 October 2006 10 January 2009 Naval Station Norfolk, Norfolk, Virginia

1975–1989

One of the first major operations in which the ships were involved was Operation Eagle Claw
Operation Eagle Claw
Operation Eagle Claw was an American military operation ordered by President Jimmy Carter to attempt to put an end to the Iran hostage crisis by rescuing 52 Americans held captive at the U.S. Embassy in Tehran, Iran on 24 April 1980...

 launched by USS Nimitz in 1980 after she had deployed to the Indian Ocean
Indian Ocean
The Indian Ocean is the third largest of the world's oceanic divisions, covering approximately 20% of the water on the Earth's surface. It is bounded on the north by the Indian Subcontinent and Arabian Peninsula ; on the west by eastern Africa; on the east by Indochina, the Sunda Islands, and...

 in response to the taking of hostages
Iran hostage crisis
The Iran hostage crisis was a diplomatic crisis between Iran and the United States where 52 Americans were held hostage for 444 days from November 4, 1979 to January 20, 1981, after a group of Islamist students and militants took over the American Embassy in Tehran in support of the Iranian...

 in the U.S. embassy in Tehran
Tehran
Tehran , sometimes spelled Teheran, is the capital of Iran and Tehran Province. With an estimated population of 8,429,807; it is also Iran's largest urban area and city, one of the largest cities in Western Asia, and is the world's 19th largest city.In the 20th century, Tehran was subject to...

. Although initially part of the U.S. Atlantic Fleet
U.S. Atlantic Fleet
The United States Fleet Forces Command is an Atlantic Ocean theater-level component command of the United States Navy that provides naval resources that are under the operational control of the United States Northern Command...

, Eisenhower relieved Nimitz in this operation after her service in the Mediterranean Sea
Mediterranean Sea
The Mediterranean Sea is a sea connected to the Atlantic Ocean surrounded by the Mediterranean region and almost completely enclosed by land: on the north by Anatolia and Europe, on the south by North Africa, and on the east by the Levant...

. Nimitz conducted a Freedom of Navigation
Freedom of Navigation
Freedom of Navigation is a principle of customary International Law that, apart from the exceptions provided for in international law, ships flying the flag of any state shall not suffer interference from other states. This right is now also codified as article 87a of the 1982 United Nations...

 exercise alongside the aircraft carrier USS Forrestal in August 1981 in the Gulf of Sidra
Gulf of Sidra
Gulf of Sidra is a body of water in the Mediterranean Sea on the northern coast of Libya; it is also known as Gulf of Sirte or the Great Sirte or Greater Syrtis .- Geography :The Gulf of Sidra has been a major centre for tuna fishing in the Mediterranean for centuries...

, near Libya
Libya
Libya is an African country in the Maghreb region of North Africa bordered by the Mediterranean Sea to the north, Egypt to the east, Sudan to the southeast, Chad and Niger to the south, and Algeria and Tunisia to the west....

. During this exercise, two of the ship's F-14 Tomcats shot down two Libyan aircraft in what became known as the Gulf of Sidra incident
Gulf of Sidra incident (1981)
In the first Gulf of Sidra incident, 19 August 1981, two Libyan Su-22 Fitter attack aircraft were shot down by two American F-14 Tomcats off of the Libyan coast.-Background:...

. In 1987, Vinson participated in the first U.S. carrier deployment in the Bering Sea
Bering Sea
The Bering Sea is a marginal sea of the Pacific Ocean. It comprises a deep water basin, which then rises through a narrow slope into the shallower water above the continental shelves....

, and Nimitz provided security during the 1988 Olympic Games
1988 Summer Olympics
The 1988 Summer Olympics, officially known as the Games of the XXIV Olympiad, were an all international multi-sport events celebrated from September 17 to October 2, 1988 in Seoul, South Korea. They were the second summer Olympic Games to be held in Asia and the first since the 1964 Summer Olympics...

 in Seoul
Seoul
Seoul , officially the Seoul Special City, is the capital and largest metropolis of South Korea. A megacity with a population of over 10 million, it is the largest city proper in the OECD developed world...

.

1990–2000

The two most significant deployments the Nimitz class was involved in during the 1990s were the Gulf War
Gulf War
The Persian Gulf War , commonly referred to as simply the Gulf War, was a war waged by a U.N.-authorized coalition force from 34 nations led by the United States, against Iraq in response to Iraq's invasion and annexation of Kuwait.The war is also known under other names, such as the First Gulf...

 and its aftermath, and Operation Southern Watch
Operation Southern Watch
Operation Southern Watch was an operation conducted by Joint Task Force Southwest Asia with the mission of monitoring and controlling airspace south of the 32nd Parallel in Iraq, following the 1991 Gulf War until the 2003 invasion of Iraq.-Summary:Operation Southern Watch began on 27 August 1992...

 in southern Iraq
Iraq
Iraq ; officially the Republic of Iraq is a country in Western Asia spanning most of the northwestern end of the Zagros mountain range, the eastern part of the Syrian Desert and the northern part of the Arabian Desert....

. All active vessels were engaged in both of these to some extent, with Operation Southern Watch continuing until 2003. However, most carriers in operation in Operation Desert Shield and Operation Desert Storm played supporting roles, with only Roosevelt playing an active part in combat operations. Throughout the 1990s and more recently, Nimitz-class carriers have been deployed as part of humanitarian missions. While deployed in the Gulf War, Lincoln was diverted to the Indian Ocean to participate alongside 22 other ships in Operation Fiery Vigil
Operation Fiery Vigil
Operation Fiery Vigil was the emergency evacuation of all non-essential military and United States Department of Defense civilian personnel and their dependents from Clark Air Base and U.S. Naval Base Subic Bay during the June 1991 volcanic eruption of Mount Pinatubo in the Philippines...

, evacuating civilians following the eruption of Mt. Pinatubo on Luzon Island in the Philippines
Philippines
The Philippines , officially known as the Republic of the Philippines , is a country in Southeast Asia in the western Pacific Ocean. To its north across the Luzon Strait lies Taiwan. West across the South China Sea sits Vietnam...

. In October 1993, Lincoln deployed to Somalia
Somalia
Somalia , officially the Somali Republic and formerly known as the Somali Democratic Republic under Socialist rule, is a country located in the Horn of Africa. Since the outbreak of the Somali Civil War in 1991 there has been no central government control over most of the country's territory...

 to assist UN humanitarian operations there, spending four weeks flying patrols over the area around Mogadishu
Mogadishu
Mogadishu , popularly known as Xamar, is the largest city in Somalia and the nation's capital. Located in the coastal Benadir region on the Indian Ocean, the city has served as an important port for centuries....

 while supporting U.S. troops during Operation Restore Hope. The same ship also participated in Operation Vigilant Sentinel
Operation Vigilant Sentinel
Operation Vigilant Sentinel was a response to Saddam Hussein advance of its military forces on the border with Kuwait. The United States deployed the 74th Air Control Squadron to Kuwait on August 24, 1995. The specific battle management functions the 74th Air Control Squadron and its counterparts...

 in the Persian Gulf
Persian Gulf
The Persian Gulf, in Southwest Asia, is an extension of the Indian Ocean located between Iran and the Arabian Peninsula.The Persian Gulf was the focus of the 1980–1988 Iran-Iraq War, in which each side attacked the other's oil tankers...

 in 1995. Roosevelt flew patrols in support of the Kurd
Kürd
Kürd or Kyurd or Kyurt may refer to:*Kürd Eldarbəyli, Azerbaijan*Kürd Mahrızlı, Azerbaijan*Kürd, Goychay, Azerbaijan*Kürd, Jalilabad, Azerbaijan*Kürd, Qabala, Azerbaijan*Qurdbayram, Azerbaijan...

s over northern Iraq as part of Operation Provide Comfort
Operation Provide Comfort
Operation Provide Comfort and Provide Comfort II were military operations by the United States and some of its Gulf War allies, starting in April 1991, to defend Kurds fleeing their homes in northern Iraq in the aftermath of the Persian Gulf War and deliver humanitarian aid to them.-Operation...

 in 1991. In 1996, George Washington played a peacekeeping role in Operation Decisive Endeavor in Bosnia and Herzegovina
Bosnia and Herzegovina
Bosnia and Herzegovina , sometimes called Bosnia-Herzegovina or simply Bosnia, is a country in Southern Europe, on the Balkan Peninsula. Bordered by Croatia to the north, west and south, Serbia to the east, and Montenegro to the southeast, Bosnia and Herzegovina is almost landlocked, except for the...

. In 1999, Roosevelt was called to the Ionian Sea
Ionian Sea
The Ionian Sea , is an arm of the Mediterranean Sea, south of the Adriatic Sea. It is bounded by southern Italy including Calabria, Sicily and the Salento peninsula to the west, southern Albania to the north, and a large number of Greek islands, including Corfu, Zante, Kephalonia, Ithaka, and...

 to support Operation Allied Force
Operation Allied Force
The NATO bombing of Yugoslavia was NATO's military operation against the Federal Republic of Yugoslavia during the Kosovo War. The strikes lasted from March 24, 1999 to June 10, 1999...

 alongside other NATO militaries.

2001–present

Truman
USS Harry S. Truman (CVN-75)
USS Harry S. Truman is the eighth Nimitz-class supercarrier of the United States Navy, named after the 33rd President of the United States, Harry S. Truman. HSTs callsign is Lone Warrior and is currently homeported at Naval Station Norfolk, Virginia.Harry S...

s maiden deployment
Maiden voyage
The maiden voyage of a ship, aircraft or other craft is the first journey made by the craft after shakedown. A number of traditions and superstitions are associated with it....

 was in November 2000. The carrier's air wing flew 869 combat sorties in support of Operation Southern Watch
Operation Southern Watch
Operation Southern Watch was an operation conducted by Joint Task Force Southwest Asia with the mission of monitoring and controlling airspace south of the 32nd Parallel in Iraq, following the 1991 Gulf War until the 2003 invasion of Iraq.-Summary:Operation Southern Watch began on 27 August 1992...

, including a strike on Iraqi air defense sites on 16 February 2001, in response to Iraqi surface-to-air missile
Surface-to-air missile
A surface-to-air missile or ground-to-air missile is a missile designed to be launched from the ground to destroy aircraft or other missiles...

 fire against United Nations coalition forces.

After the 11 September attacks, Vinson and Roosevelt were among the first warships to participate in Operation Enduring Freedom in Afghanistan
Afghanistan
Afghanistan , officially the Islamic Republic of Afghanistan, is a landlocked country located in the centre of Asia, forming South Asia, Central Asia and the Middle East. With a population of about 29 million, it has an area of , making it the 42nd most populous and 41st largest nation in the world...

. Vinson sailed towards the Persian Gulf intending to support Operation Southern Watch
Operation Southern Watch
Operation Southern Watch was an operation conducted by Joint Task Force Southwest Asia with the mission of monitoring and controlling airspace south of the 32nd Parallel in Iraq, following the 1991 Gulf War until the 2003 invasion of Iraq.-Summary:Operation Southern Watch began on 27 August 1992...

 in July 2001. This changed in response to the attacks, and the ship changed course to travel towards the North Arabian Sea
Arabian Sea
The Arabian Sea is a region of the Indian Ocean bounded on the east by India, on the north by Pakistan and Iran, on the west by the Arabian Peninsula, on the south, approximately, by a line between Cape Guardafui in northeastern Somalia and Kanyakumari in India...

, where she launched the first airstrikes in support of the operation on 7 October 2001. Following the attacks, Stennis and Washington participated in Operation Noble Eagle
Operation Noble Eagle
Operation Noble Eagle is the name given to military operations related to homelandsecurity and support to federal, state, and local agencies...

, carrying out homeland security operations off the West Coast of the United States
West Coast of the United States
West Coast or Pacific Coast are terms for the westernmost coastal states of the United States. The term most often refers to the states of California, Oregon, and Washington. Although not part of the contiguous United States, Alaska and Hawaii do border the Pacific Ocean but can't be included in...

. All active ships have been involved to some extent in Iraq and Afghanistan since that time. This included the invasion in 2003, as well as providing subsequent support for Operation Iraqi Freedom since then.

The carriers have also provided aid after natural disasters; in 2005, Lincoln supported Operation Unified Assistance
Operation Unified Assistance
Operation Unified Assistance is the name of the United States military's response to the tsunami of 2004.-Overview:On 28 December, the first elements of the Combined Support Force were deployed to Utapao, Thailand following that country's approval of the use of that base.More than 12,600...

 in Indonesia
Indonesia
Indonesia , officially the Republic of Indonesia , is a country in Southeast Asia and Oceania. Indonesia is an archipelago comprising approximately 13,000 islands. It has 33 provinces with over 238 million people, and is the world's fourth most populous country. Indonesia is a republic, with an...

 after the December 2004 tsunami
2004 Indian Ocean earthquake
The 2004 Indian Ocean earthquake was an undersea megathrust earthquake that occurred at 00:58:53 UTC on Sunday, December 26, 2004, with an epicentre off the west coast of Sumatra, Indonesia. The quake itself is known by the scientific community as the Sumatra-Andaman earthquake...

, and Truman provided aid after Hurricane Katrina
Hurricane Katrina
Hurricane Katrina of the 2005 Atlantic hurricane season was a powerful Atlantic hurricane. It is the costliest natural disaster, as well as one of the five deadliest hurricanes, in the history of the United States. Among recorded Atlantic hurricanes, it was the sixth strongest overall...

 later in 2005. The Reagan Carrier Strike Group performed humanitarian assistance and disaster relief operations in the Philippines
Philippines
The Philippines , officially known as the Republic of the Philippines , is a country in Southeast Asia in the western Pacific Ocean. To its north across the Luzon Strait lies Taiwan. West across the South China Sea sits Vietnam...

 in June 2008 after Typhoon Fengshen
Typhoon Fengshen (2008)
Typhoon Fengshen was the sixth named storm and the fourth typhoon recognised by the Japan Meteorological Agency...

, which killed hundreds from the central island regions and the main island of Luzon
Luzon
Luzon is the largest island in the Philippines. It is located in the northernmost region of the archipelago, and is also the name for one of the three primary island groups in the country centered on the Island of Luzon...

. In January 2010 Vinson operated off Haiti
Haiti
Haiti , officially the Republic of Haiti , is a Caribbean country. It occupies the western, smaller portion of the island of Hispaniola, in the Greater Antillean archipelago, which it shares with the Dominican Republic. Ayiti was the indigenous Taíno or Amerindian name for the island...

, providing aid and drinking water to earthquake
2010 Haiti earthquake
The 2010 Haiti earthquake was a catastrophic magnitude 7.0 Mw earthquake, with an epicentre near the town of Léogâne, approximately west of Port-au-Prince, Haiti's capital. The earthquake occurred at 16:53 local time on Tuesday, 12 January 2010.By 24 January, at least 52 aftershocks...

 survivors as part of the U.S. led Operation Unified Response
Operation Unified Response
Operation Unified Response is the United States military's response to the 2010 Haiti earthquake. It is being conducted by Joint Task Force Haiti and commanded by United States Southern Command Military Deputy Commander Lieutenant General Ken Keen, although the overall U.S...

, alongside other major warships and hospital ship
Hospital ship
A hospital ship is a ship designated for primary function as a floating medical treatment facility or hospital; most are operated by the military forces of various countries, as they are intended to be used in or near war zones....

 Comfort
USNS Comfort (T-AH-20)
USNS Comfort is the third United States Navy ship to bear the name Comfort, and the second to join the navy fleet. The USNS prefix identifies the Comfort as a non-commissioned ship owned by the U.S. Navy and crewed by civilians. In accordance with the Geneva Conventions, USNS Comfort and her...

.

Refueling Complex Overhaul

In order to refuel their nuclear power plants, the carriers each undergo a Refueling Complex Overhaul (RCOH) once in their service lives. This is also the most substantial overhaul the ships undergo while in service and involves bringing the vessels' equipment up to the standards of the newest ships. The ship is placed in dry dock, and essential maintenance is carried out including painting of the hull below the waterline and replacement of electrical and mechanical components such as valves. Because of the large time periods between the ships' constructions, the armament and designs of the newer ships are more modern than those of the older ships. In RCOH, the older ships are refitted to the standards of the newer ships, which can include major upgrades to the flight deck, aircraft catapult
Aircraft catapult
An aircraft catapult is a device used to launch aircraft from ships—in particular aircraft carriers—as a form of assisted take off. It consists of a track built into the flight deck, below which is a large piston or shuttle that is attached through the track to the nose gear of the aircraft, or in...

s and combat systems as well as other upgrades such as improved radar
Radar
Radar is an object-detection system which uses radio waves to determine the range, altitude, direction, or speed of objects. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, weather formations, and terrain. The radar dish or antenna transmits pulses of radio...

 systems, although precise details can vary significantly between the ships. The improvements normally take around four years to complete. The RCOH for USS Theodore Roosevelt, which began in 2009, will reportedly cost US$ 2.4 billion. Planned Incremental Availability is a similar procedure, although it is less substantial and does not involve refueling of the nuclear power plants.

Symbolic and diplomatic roles

Because of their status as the largest warships in the U.S. Navy, the deployment of an aircraft carrier can fulfill a symbolic role, not just in terms of a deterrent to an enemy, but often as a diplomatic tool, in strengthening relations with allies and potential allies. The latter of these functions can take place either as a single visit to a country, in which senior naval officers are allowed to observe the operating of the carrier and to interact with its senior officers, or as part of an international task force. This can be in combat operations, such as Operation Allied Force
Operation Allied Force
The NATO bombing of Yugoslavia was NATO's military operation against the Federal Republic of Yugoslavia during the Kosovo War. The strikes lasted from March 24, 1999 to June 10, 1999...

 in 1999, or other deployments involving training, such as RIMPAC
RIMPAC
RIMPAC, the Rim of the Pacific Exercise, is the world's largest international maritime exercise. Conducted biennially , it is hosted and administered by the United States Navy, with the United States Marine Corps, United States Coast Guard, and Hawaii National Guard forces under the leadership of...

. In addition, carriers have participated in international Maritime Security Operations
Maritime Security Operations
Maritime Security Operations is a term for the actions of modern naval forces to "combat sea–based terrorism and other illegal activities, such as hijacking, piracy, and slavery, also known as human trafficking." Ships assigned to such operations may also assist seafaring vessels in distress...

, combating piracy
Piracy
Piracy is an act of robbery or criminal violence at sea. The term can include acts committed on land, in the air, or in other major bodies of water or on a shore. It does not normally include crimes committed against persons traveling on the same vessel as the perpetrator...

 in the Persian Gulf
Persian Gulf
The Persian Gulf, in Southwest Asia, is an extension of the Indian Ocean located between Iran and the Arabian Peninsula.The Persian Gulf was the focus of the 1980–1988 Iran-Iraq War, in which each side attacked the other's oil tankers...

 and off the coast of Somalia
Somalia
Somalia , officially the Somali Republic and formerly known as the Somali Democratic Republic under Socialist rule, is a country located in the Horn of Africa. Since the outbreak of the Somali Civil War in 1991 there has been no central government control over most of the country's territory...

.

Accidents and incidents

As on most large warships, there have been several incidents involving the death or injury of one or more crew members, although most have involved freak accidents or failures, such as a man overboard
Man overboard
Man overboard is a situation in which a person has fallen from a boat or ship into the water and is in need of rescue. Whoever sees the person's fall should shout "man overboard" to alert other crew members and attempt to maintain visual contact with the person in the water...

 as a result of poor weather. One of the highest-profile incidents was on 26 May 1981, when an EA-6B Prowler
EA-6 Prowler
The Northrop Grumman EA-6B Prowler is a twin-engine, mid-wing electronic warfare aircraft modified from the basic A-6 Intruder airframe. The EA-6B has been in service with the U.S...

 crashed on the flight deck of Nimitz, killing 14 crewmen and injuring 45 others. Forensic testing of the personnel involved showed that several tested positive for marijuana. While this was not in itself found to have directly caused the crash, the findings of the investigation provoked the introduction of mandatory drug testing of all service personnel.

In cases of ditched aircraft, pilots have been able to eject safely in several cases. However, fatal aircraft crashes have occurred; in 1994, Lt.
Lieutenant
A lieutenant is a junior commissioned officer in many nations' armed forces. Typically, the rank of lieutenant in naval usage, while still a junior officer rank, is senior to the army rank...

 Kara Hultgreen
Kara Hultgreen
Kara Spears Hultgreen , was a Lieutenant in the United States Navy, and the first female naval carrier-based fighter pilot. She was killed just months after she was certified for combat, when her F-14 Tomcat crashed into the sea on final approach to...

, the first female F-14 Tomcat pilot, was killed while attempting to land on board Lincoln during a training exercise.

Fires have also caused damage to the ships; in May 2008, while being transferred to her current homeport at Yokosuka Naval Base
United States Fleet Activities Yokosuka
U.S. Fleet Activities Yokosuka, or Commander, Fleet Activities Yokosuka is a United States Navy base, in Yokosuka, Japan. Its mission is to maintain and operate base facilities for the logistic, recreational, administrative support and service of the U.S. Naval Forces Japan, U.S. 7th Fleet and...

 in Yokosuka, Japan, George Washington suffered a serious fire which cost US$70 million in repairs and injured 37 sailors. The fire was caused by unauthorized smoking in an area near improperly stored flammable refrigerant.

Future

Nimitz class ships were designed to have a fifty-year service life. At the end of the service life, ships will be decommissioned
Ship decommissioning
To decommission a ship is to terminate her career in service in the armed forces of her nation. A somber occasion, it has little of the elaborate ceremony of ship commissioning, but carries significant tradition....

. This process will first take place on Nimitz and is estimated to cost from US$750 to $900 million. This compares with an estimate of US$53 million for a conventionally powered carrier. Most of the difference in cost is attributed to the deactivation
Ship-Submarine recycling program
The Ship/Submarine Recycling Program is the process the United States Navy uses to dispose of decommissioned nuclear vessels. SRP takes place only at the Puget Sound Naval Shipyard in Bremerton, Washington, but the preparations can begin elsewhere....

 of the nuclear power plants and safe removal of radioactive material and other contaminated equipment. A new class of carriers, the Gerald R. Ford class, is being constructed to replace previous vessels after decommissioning. Ten of these are expected, and the first will enter service in 2015 to replace USS Enterprise
USS Enterprise (CVN-65)
USS Enterprise , formerly CVA-65, is the world's first nuclear-powered aircraft carrier and the eighth US naval vessel to bear the name. Like her predecessor of World War II fame, she is nicknamed the "Big E". At , she is the longest naval vessel in the world...

. The rest of these new carriers will gradually replace the oldest Nimitz vessels as they reach the end of their service life. The new carriers will have a similar design to Bush (using an almost identical hull shape) but will also have further technological and structural improvements.

See also

  • List of aircraft carriers
  • List of naval ship classes in service
  • Naval aviation
    Naval aviation
    Naval aviation is the application of manned military air power by navies, including ships that embark fixed-wing aircraft or helicopters. In contrast, maritime aviation is the operation of aircraft in a maritime role under the command of non-naval forces such as the former RAF Coastal Command or a...



External links

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