The Nimitz Class aircraft carriers are the largest warships ever built. With over 6 000 personnel (crew and aircrew), the carrier has a displacement of 102 000 tonne, and a flight deck length of 332, 9 metre. All seven nuclear-powered Nimitz class carriers have been built by 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 latest, USS Harry S. Truman, was commissioned in July 1998. Other hulls are USS Dwight D Eisenhower (CVN 69), Oct 1977; USS Carl Vinson (CVN 70), Mar 1982; USS Theodore Roosevelt (CVN 71), Oct 1986; USS Abraham Lincoln (CVN 72), Nov 1989; USS George Washington (CVN 73), Jul 1992; USS John C Stennis (CVN 74), Dec 1995; USS Ronald Reagan (CVN 76), Mar 2003.

The tenth and last Nimitz Class, CVN 77, will be built by Northrop Grumman Ship Systems and will enter service in 2008. This will be the first transition ship to a new class of carriers (CVNX) (to start construction in 2007) and will incorporate new technologies including a new multi-function radar system, volume search radar and open architecture information network, and a significantly reduced crew requirement.

Design

The more recent Nimitz Class carriers (CVN72-CVN76) have a displacement of 102 000 tonne fully loaded. They have a length of 317 metre and beam of 40,8 metre. The carrier reaches a maximum speed of over 30 knots, and accommodates a complement of 3 184 personnel (with 203 officers); 2 800 aircrew (with 366 officers); and 70 flag (with 25 officers).

Aircraft

The 50 TACAIR air wing includes the following fixed wing aircraft 20 F-14D "Bomcats" (Tomcats with a strike role), 36 F/A-18 Hornets, 8 S-3A/B Vikings, 4 E-2C Hawkeyes, and 4 EA-6B Prowlers; and the following helicopters 4 SH-60F and 2 HH-60H Seahawks. Air wings can be varied 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 off Haiti.

The flight deck measures 333 metre x 77 metre 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.

Missiles

The more recently built carriers are armed with three Raytheon GMLS Mk 29 eight-cell launchers for Nato Seasparrow surface-to-air missiles. Seasparrow has a range of 14,5 km and semi-active radar terminal guidance. The carriers are also being fitted with the Raytheon RAM (Rolling Airframe) missile system, which provides short-range defence against incoming anti-ship missiles, including sea-skimming missiles.

Guns

There are four Raytheon/General Dynamics 20 mm Phalanx 6-barrelled Mk 15 close-in weapon systems which have a firing rate of 3 000 rounds/min and a range of 1,5 km.

Countermeasures

Decoys include four Sippican SRBOC (Super Rapid Bloom Off-Board Chaff) 6-barrelled Mk 36 decoy launchers, which deploy infrared flares and chaff, SSTDS torpedo defence system and AN/SLQ-25 Nixie torpedo countermeasures system, from Sensytech Inc of Newington, Virginia.

The Raytheon AN/SLQ-32(V) electronic warfare system detects hostile radar emissions by two sets of antennae and the system analyses the pulse repetition rate, the scan mode, the scan period, and the frequency. The system identifies the threat and direction, provides a warning signal and interfaces to the ship's countermeasures systems.

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 Mk 91 Mod 1 MFCS directors for the Seasparrow missile. USS Nimitz is being fitted with the SSDS Mk2 Mod 0 ship self-defense system, developed by Raytheon. The SSDS will provide automated self-defence against anti-ship cruise missiles (ASCMs) by integrating and co-ordinating the ships weapon and electronic warfare systems.

Sensors

Air search radars include the ITT SPS-48E 3-D, operating at E/F-band; Raytheon SPS49(V)5, C/D-band; and Raytheon Mk 23 TAS, D-band. Surface search radar is the Northrop Grumman Norden Systems SPS-67V, operating at G-band.

Propulsion

The nuclear-powered carrier has two General Electric pressurised water reactors driving four turbines of 260 000 hp (194 MW) and four shafts. There are four emergency diesels of 10 720 hp (8 MW).

With acknowledgement to Naval Technology Website.