Independence class littoral combat ship

The Independence class is a class of littoral combat ships built for the United States Navy.

The hull design evolved from a project at Austal to design a 40 knot cruise ship. That hull design evolved into the high-speed trimaran ferry Benchijigua Express and the Independence class was then proposed by General Dynamics and Austal as a contender for USN plans to build a fleet of small, multipurpose warships to operate in the littoral zone. Two ships were approved, to compete with Lockheed Martin's Freedom class design for a construction contract of up to 55 vessels.

As of 2010, the lead ship is active, while a second ship is under construction. Despite initial plans to only accept one of the Independence and Freedom classes, the USN has requested that Congress order ten ships of each class.

Planning for a class of small, multipurpose warships to operate in the littoral zone began in the early 2000s. In July 2003, a proposal by General Dynamics (partnering with Austal USA, the American subsidiary of Australian shipbuilder Austal) was approved by the USN, with a contract for two vessels. These would then be compared to two ships built by Lockheed Martin to determine which design would be taken up by the Navy for a production run of up to 55 ships.

The first ship, USS Independence was laid down at the Austal USA shipyard in Mobile, Alabama, on 19 January 2006. The planned second ship was cancelled in November 2007, but reordered in May 2009, and laid down in December of that year as USS Coronado, shortly before Independence was launched.

The development and construction of Independence as of June 2009 was running at 220% over-budget. The total projected cost for the ship is $704 million. The Navy had originally projected the cost at $220 million. Independence began builder's trials in July 2009, three days behind schedule because of maintenance issues. A leak in the port gas turbine saw the order of trials altered, but builder's and acceptance trials were completed by November. And although her first INSURV inspection revealed 2,080 deficiencies, these were rectified in time for the ship to be handed over to the USN in mid-December, and commissioned in mid-January 2010.

Navy leaders said that the fixed price competition offered the Austal design an equal shot, in spite of its excess size and cost and limited service.

After much inconsistency on how testing and orders were to proceed, in November 2010, the USN asked that Congress approve ten of both the Independence and Freedom classes.

The Independence class design began life at Austal as a platform for a high speed cruise ship. The principal requirements of that project were speed, stability and passenger comfort and Austal's team determined that the trimaran hull form offered significant passenger comfort and stability advantages over both a catamaran and a monohull. The high speed cruise ship project evolved into Austal's commercial high-speed trimaran ferry Benchijigua Express. The ships are 127.4 m (418 ft) long, with a beam of 31.6 m (104 ft), and a draft of 13 ft (3.96 m). Their displacement is rated at 2,176 tons light, 2,784 tons full, and 608 tons deadweight.

The standard ship's company is 40-strong, although this can increase depending on the ship's role with mission-specific personnel. The habitability area is located under the bridge where bunks for ships personnel are situated. The helm is controlled by joysticks instead of traditional steering wheels.

Although the trimaran hull increases the total surface area, it is still able to reach sustainable speeds of about 50 knots (93 km/h; 58 mph), with a range of 10,000 nautical miles (19,000 km; 12,000 mi).[citation needed] Austal claims that the design will use a third less fuel than the competing Freedom-class, but the Congressional Budget Office found that fuel would account for 18 percent or less of the total lifetime cost of Freedom.

The Independence class carries a default armament for self-defense, and command and control. However unlike traditional fighting ships with fixed armament such as guns and missiles, tailored mission modules can be configured for one mission package at a time. Modules may consist of manned aircraft, unmanned vehicles, off-board sensors, or mission-manning detachments.

The interior volume and payload is greater than some destroyers and is sufficient to serve as a high-speed transport and maneuver platform. The mission bay is 15,200 square feet (1,410 m2), and takes up most of the deck below the hangar and flight deck. With 11,000 cubic metres (390,000 cu ft) of payload volume, it was designed with enough payload and volume to carry out one mission with a separate mission module in reserve, allowing the ship to do multiple missions without having to be refitted.

One Mobicon Flexible Container Handling System is carried on each ship in order to move mission containers.

In addition to cargo or container-sized mission modules, the bay can carry four lanes of multiple Strykers, armored Humvees, and their associated troops. An elevator allows air transport of packages the size of a 20-foot-long (6.1 m) shipping container that can be moved into the mission bay while at sea. A side access ramp allows for vehicle roll-on/roll-off loading to a dock and allows the ship to transport the Expeditionary Fighting Vehicle.

The Raytheon Evolved SeaRAM missile defense system is installed on the hangar roof. The SeaRAM combines the sensors of the Phalanx 1B close-in weapon system with an 11-missile launcher for the Rolling Airframe Missile (RAM), creating an autonomous system.

The Independence class ships also has an integrated LOS Mast, Sea Giraffe 3D Radar and SeaStar Safire FLIR. Northrop Grumman has demonstrated sensor fusion of on and off-board systems in the Integrated Combat Management System (ICMS) used on the LCS. Side and forward surfaces are angled for reduced radar profile. In addition, H-60 series helicopters provide airlift, rescue, anti-submarine, radar picket and anti-ship capabilities with torpedoes and missiles.

The flight deck, 1,030 m2 (11,100 sq ft), can support the operation of two SH-60 Seahawk helicopters, multiple unmanned aerial vehicles, or one CH-53 Sea Stallion helicopter. The trimaran hull will allow flight operations up to sea state 5.

The vessels have an Interior Communications Center that can be curtained off from the rest of bridge instead of the heavily protected Combat Information Center found on Navy warships.

The control system for this class is provided by General Dynamics, while Lockheed provides their own control system for their variant of the LCS.

Austal has proposed a much smaller and slower trimaran, called the 'Multi-Role Vessel' or 'Multi-Role Corvette'. Though it is only half the size of their LCS design, it would still be useful for border protection and counter piracy operations.