The Nimitz-class aircraft carriers were the largest warships ever built until the commissioning of USS Gerald R Ford in 2017. With over 6,000 personnel (crew and aircrew), the carrier has a displacement of 102,000t and a flight deck length of 332.9m.
All ten nuclear-powered Nimitz-class carriers were built by Huntington Ingalls Industries Newport News Shipbuilding (now Northrop Grumman Ship Systems) based in Virginia.
Tasked with a multi-mission attack / ASW role, the first of class, USS Nimitz, was commissioned in 1975. The last of the class, USS George HW Bush (CVN 77), was commissioned in January 2009.
Other hulls include USS Dwight D Eisenhower (CVN 69) – October 1977; USS Carl Vinson (CVN 70) – March 1982; USS Theodore Roosevelt (CVN 71) – October 1986; USS Abraham Lincoln (CVN 72) – November 1989; USS George Washington (CVN 73), July 1992; USS John C Stennis (CVN 74) – December 1995, USS Harry S Truman (CVN 75) – July 1998 and USS Ronald Reagan (CVN 76) – July 2003.
USS Ronald Reagan (CVN 76) made its first operational deployment between January and May 2006, in support of Operation Iraqi Freedom and Enduring Freedom in the Arabian Gulf.
In September 2008, USS George Washington (CVN 73) arrived at its new homeport of Yokosuka, Japan. It replaced USS Kitty Hawk, which was decommissioned in May 2009, as the flagship of the US 7th fleet.
The keel for the tenth and last Nimitz-class, USS George HW Bush (CVN 77), was laid in September 2003. The carrier was christened in October 2006 and entered service in 2009. The vessel has a modernised island house with a new radar tower and transparent armour windows, as well as upgraded navigation and communications systems. It has a new aircraft launch and recovery system and JP-5 fuel system for improved storage and aircraft fuel handling.
It is the first transition ship to a new class of carriers, Gerald R Ford (CVN 78) (also known as CVN 21 and CVNX), commissioned in July 2017. Huntington Ingalls Industries Newport News Shipbuilding is the prime contractor for the programme and Raytheon is responsible for weapons system integration. CVN 78 incorporates new technologies, including a new multi-function radar system, volume search radar and open architecture information network, providing a significantly reduced crew requirement and a new nuclear power plant.
Nimitz-class carrier design
The more recent Nimitz-class carriers (CVN72-CVN76) have a displacement of 102,000t when fully loaded. They have a length of 317m and beam of 40.8m.
The carrier reaches a maximum speed of over 30k and can accommodate 3,184 personnel (with 203 officers), 2,800 aircrew (with 366 officers) and 70 flag (with 25 officers).
Nimitz-class aircraft details
The 50 TACAIR air wing includes up to 82 aircraft. Typically this would be 12 F/A-18E/F Hornets, 36 F/A-18 Hornets, four E-2C Hawkeyes and four EA-6B Prowlers fixed-wing and helicopters, including four SH-60F and two HH-60H Seahawks. The carrier can also deploy S-3B Viking aircraft, but these were phased out and replaced with the F/A-18E/F Super Hornet. The S-3B Viking was finally decommissioned in January 2009.
The last operational deployment of the F-14, used in US carriers since 1972, was in March 2006. The F-14 was decommissioned in September 2006.
Air wings can be customised according to the nature of the operation. For example, in 1994, 50 army helicopters replaced the usual air wing on the USS Dwight D Eisenhower during operations near Haiti.
The flight deck measures 333m x 77m and is equipped with four lifts, four steam-driven catapults and four arrester wires. The carrier is capable of launching one aircraft every 20 seconds.
In April 2005, the US Naval air systems command (NAVAIR) selected General Atomics Electromagnetic Systems for the system development and demonstration (SDD) phase of the advanced arresting gear (AAG) programme to provide a new arrestor system for USN carriers.
The more recently built carriers are armed with three Raytheon GMLS mk29 eight-cell launchers for Nato Sea Sparrow surface-to-air missiles. Sea Sparrow has a range of 14.5km and semi-active radar terminal guidance.
The carriers are fitted with the Raytheon RAM (rolling airframe missile) system, which provides short-range defence against incoming anti-ship missiles, including sea-skimming missiles.
USS Stennis was fitted with RAM in 2005 and began firing trials of the system in June 2006. One Sea Sparrow mount and one Phalanx CIWS mount were removed to fit the RAM.
USS John C Stennis was the first carrier to fire the evolved Sea Sparrow missile (ESSM) in October 2008.
Nimitz aircraft carrier weapons
There are four Raytheon / General Dynamics 20mm Phalanx six-barrelled Mk 15 close-in weapon systems that have a firing rate of 3,000 rounds a minute and a range of 1.5km.
Decoys include four Sippican super rapid bloom off-board chaff (SRBOC), six-barrelled mk36 decoy launchers, which deploy infrared flares and chaff, SSTDS torpedo defence system and AN/SLQ-25 Nixie torpedo countermeasures system from Argon ST of Fairfax, Virginia.
The Raytheon AN/SLQ-32(V) electronic warfare system detects hostile radar emissions by two sets of antennae and the system analyses pulse repetition rate, scan mode, scan period and frequency. The system identifies the threat and direction, provides a warning signal and interfaces to the ship’s countermeasures systems.
Nimitz-class carrier combat systems
The carriers’ combat data systems are based around the block 0 or 1 naval tactical and advanced combat direction system (ACDS) with communications links 4A, 11, 14 and 16. Weapons control is managed by three mk91 mod 1 MFCS directors for the Sea Sparrow missile.
USS Nimitz, USS Ronald Reagan and USS John Stennis were fitted with the SSDS mk2 mod 0 ship self-defence system developed by Raytheon. The SSDS will provide automated self-defence against anti-ship cruise missiles (ASCMs) by integrating and coordinating the ship’s weapon and electronic warfare systems.
USS Nimitz was fitted with the Lockheed Martin TIS (tactical input segment) digital reconnaissance processing system, which can receive real-time imagery from airborne sensors.
Nimitz-class sensors and propulsion
Air search radars include the ITT SPS-48E 3-D, operating at E/F-band, Raytheon SPS49(V)5, C/D-band and Raytheon mk23 TAS, D-band. Surface search radar is the Northrop Grumman Norden Systems SPS-67V, operating at G-band.
Four vessels in class, CVN 70, CVN 73, CVN 74 and CVN 76, feature the AN/SPS-74(V) radar to enable tracking and detection of submarine periscopes. The navy cancelled the programme and decided to procure AN/SPQ-9B periscope detection capability radars for installation on the ten hulls.
The Nimitz class will also feature AN/SPY-6(V)3 enterprise air surveillance radar (EASR) being developed by Raytheon.
The nuclear-powered carrier has two General Electric pressurised water reactors driving four turbines of 260,000hp (194MW) and four shafts. There are four emergency diesels of 10,720hp (8MW).