Freedom-class littoral combat ship

For the RCI cruise ship class, see Freedom-class cruise ship.
Freedom class
Freedom shows off her new camouflage scheme on sea trials in February 2013 before her first deployment
Class overview
Builders: Lockheed Martin
Operators:  United States Navy
Cost: $362 million[1]
Built: 2005–present
In commission: 2008–present
Building: 6
Planned: 13
Completed: 4
Active: 4
General characteristics
Type: Littoral combat ship
Displacement: 3,500 metric tons (3,900 short tons) (full load)[2]
Length: 378 ft (115 m)
Beam: 57.4 ft (17.5 m)
Draft: 12.8 ft (3.9 m)
Installed power: Electrical: 4 Isotta Fraschini V1708 diesel engines, Hitzinger generator units, 800 kW each
Propulsion: 2 Rolls-Royce MT30 36 MW gas turbines, 2 Colt-Pielstick diesel engines, 4 Rolls-Royce waterjets
Speed: 47 knots (87 km/h; 54 mph) (sea state 3)[3]
Range: 3,500 nmi (6,500 km; 4,000 mi) at 18 knots (33 km/h; 21 mph)[4]
Endurance: 21 days (336 hours)
Boats & landing
craft carried:
11 m (36 ft) RHIB, 40 ft (12 m) high-speed boats
Complement: 50 core crew, 65 with mission crew (Blue and Gold crews).[5]
Sensors and
processing systems:
Electronic warfare
& decoys:
Armament:
Aircraft carried:

The Freedom class is one of two classes of littoral combat ship built for the United States Navy.[13]

The Freedom class was proposed by Lockheed Martin as a contender for a fleet of small, multipurpose warships to operate in the littoral zone. Two ships were approved, to compete with the Independence-class design offered by General Dynamics and Austal for a construction contract of up to 55 vessels.

Despite initial plans to only accept two of the Freedom and Independence variants, the Navy has since announced plans to order up to ten additional ships of each class, for a total twelve ships per class.[14] As of 2016, four ships are active and an additional six are under construction. Starting in 2019, ships of this class will be designated as fast frigates (FF) which will include increased firepower and heavier armor.[15]

On 1 April 2016, the US Navy awarded a contract to Lockheed Martin for LCS-25, the thirteenth of the Freedom-class variants. As of April 2016, delivery of LCS-25 is expected in 2020.[16]

It was announced in early September 2016 that the first four vessels of the LCS program would be used as test ships rather than being deployed with the fleet.[17][18] This includes Freedom and Fort Worth.

Planning and construction

Freedom in February 2013 showing her large helideck and a RAM launcher on the hangar.

Planning for a class of small, multipurpose warships to operate in the littoral zone began in the early 2000s. The construction contract was awarded to Lockheed Martin's LCS team (Lockheed Martin, Gibbs & Cox, Marinette Marine, Bollinger Shipyards) in May 2004 for two vessels. These would then be compared to two ships built by Austal USA to determine which design would be taken up by the Navy for a production run of up to 55 ships.

On 15 April 2003, the Lockheed Martin LCS team unveiled their Sea Blade concept based on the hull form of the motor yacht Destriero.[19][20]

The keel of the lead ship USS Freedom was laid down in June 2005, by Marinette Marine in Marinette, Wisconsin.[21] She was christened in September 2006,[22][23] delivered to the Navy in September 2008, and commissioned that November.[24] During INSURV trials, 2,600 discrepancies were discovered, including 21 considered high-priority.[25] Not all of these were rectified before the ship entered service, as moving the ship away from Milwaukee before the winter freeze was considered a higher priority.[26]

Cost overruns during Freedom's construction combined with projected future overruns led the government to issue a "Stop-work" in January 2007 and ultimately led to the cancellation of construction of LCS-3 (the second Lockheed Martin ship) on 13 April 2007.[27] This ship was later re-ordered.

After much inconsistency on how testing and orders were to proceed, in November 2010, the Navy asked that Congress approve ten of both the Freedom and Independence variants.[28][29][30]

Design

An MH-60 Seahawk helicopter approaching USS Freedom in 2009

The ship is a semi-planing steel monohull with an aluminum superstructure. It is 377 feet (115 m) in length, displaces 3,500 metric tons, and can go faster than 45 knots (83 km/h; 52 mph). The design incorporates a large reconfigurable seaframe to allow rapidly interchangeable mission modules, a flight deck with integrated helicopter launch, recovery and handling system and the capability to launch and recover boats (manned and unmanned) from both the stern and side.

The flight deck is one and a half times larger than that of a standard surface ship, and uses a Trigon traversing system to move helicopters in and out of the hangar. The ship has two ways to launch and recover various mission packages: a stern ramp and a starboard side door near the waterline. The mission module bay has a 3-axis crane for positioning modules or cargo.[31] Problems with the electrical systems are the most serious problems with the Freedom class.[32]

The fore deck has a modular weapons zone which can be used for a 57 mm gun turret or missile launcher. A Rolling Airframe Missile launcher is mounted above the hangar for short-range defense against aircraft and cruise missiles, and .50-caliber gun mounts are provided topside. The Fleet-class unmanned surface vessel is designed for operations from Freedom variant ships.[33]

The core crew will be 40 sailors, usually joined by a mission package crew and an aviation detachment for a total crew of about 75. Automation allows a reduced crew, which greatly reduces operating costs, but workload can still be "gruelling".[34] During testing of the class lead, two ship's companies will rotate on four-month assignments.[35]

Four 750-kilowatt Fincantieri Isotta-Fraschini diesel generators provide 3 megawatts of electrical power to power the ship systems.[36]

The Congressional Budget Office estimates that fuel will account for only "8 percent to 18 percent" of the total life-cycle costs for Freedom.[37] Senator Jeff Sessions of Alabama has called the report into question and has suggested that Independence, built in his state, would be more fuel efficient and that less frequent refuelings would affect military operations beyond the cost of fuel.[38]

In 2012, a Navy cybersecurity team found major deficiencies in Lockheed's Total Ship Computing Environment, which controls the entire ship in order to reduce crewing requirements.[39][40]

Survivability has been a criticism of both Littoral Combat Ship classes, rated at level one by the Navy, compared to level two for the Oliver Hazard Perry-class guided-missile frigates (FFG) they are designed to replace. Lockheed claims the Freedom class is actually more survivable than the FFGs because Navy requirements for various survivability levels have changed since the FFGs were assessed, and because the Freedoms' hull is made of high-strength, low-weight steel that was not previously available.[41]

USS Milwaukee was the first Freedom-class LCS to be fitted with cavitation performance waterjets. The jets create partial vacuums in liquid using an improved impeller blade design. Cavitation jets do not increase the ship's top speed, but deliver 10 percent greater fuel efficiency with less noise and vibration, reduced life-cycle costs, improved maintainability, increased availability, and potentially improved efficiency at lower speeds. The Navy plans to add the new waterjets to every Freedom variant that is produced, including LCS 5, 7, 9, 11, and 13.[42] The mixed flow design was changed to an axial design to push water parallel to the shaft of the impeller.[43]

The first ships of both LCS classes were delivered before the designs were mature so that improvements could be built into future ships. Many improvements to the Freedom class came from the problems experienced by USS Freedom on its first deployment including power outages, corroded equipment, a faulty air compressor. To prevent water being taken into the anchor windlass room, the anchor winch, hydraulic unit, and mooring capstan were replaced with a single electric chain winch on the main deck, and the existing towing chain was replaced with a lighter chain. Corrosion resistance was also improved by the Impressed Current Cathodic Protection system being modified by adding protections to the water jet inlet tunnel. Starting with LCS-3, the stern transom was lengthened and buoyancy tanks were added to the stern to increase weight service and enhance stability. A significantly less complex gas turbine electric start system will be added on LCS-5 to reduce costs and lower ship weight.[43]

Starting with LCS-17, the Freedom-class ships will be equipped with the TRS-4D naval radar. The TRS-4D is an AESA radar built by Airbus Defense and Space that is similar to the one on German F125-class frigates, the difference being the LCS will have a rotating version instead of a fixed panel, the first AESA rotating radar aboard a U.S. Navy ship. It is a three-dimensional, multi-function naval radar combining mechanical and electronic azimuth scanning that delivers increased sensitivity to detect smaller targets with greater accuracy and faster track generation.[44]

SSC variant

Lockheed submitted a variety of upgrade options for Freedom-class ships to the Small Surface Combatant Task Force, aimed at transforming the Littoral Combat Ship from "niche" platforms into ships with more protection and firepower beyond Flight 0 to survive against more advanced military adversaries. With 180 metric tons of space available for mission packages, there is room for added capabilities. Anti-aircraft warfare was suggested with the installation of a SPY-1F air defense radar and permanently installed vertical launch systems (VLS). Current 118-meter length versions could house 4 to 32 VLS cells, each holding four RIM-162D Evolved Sea Sparrow Missiles or one SM-2 missile. For surface warfare, the Mk 110 cannon could be replaced with a larger gun up to the Mk 45 5-inch cannon; integration of the AGM-114L Hellfire missile for defense against fast attack craft (FAC) was also factored in.[45] Lockheed's approach was to integrate mission systems into the hull so that the ships could perform anti-submarine, anti-surface, and anti-aircraft duties without needing to swap out mission packages. Weight would be increased from 3,400 tons to 3,600 tons and the hull could be stretched an additional 7–10 m (23–33 ft). In addition to adding vertical launch tubes and a sonar, the main gun would be integrated with the stronger and more sophisticated radar.[46]

The Navy's recommendation to base the Small Surface Combatant on upgraded versions of both Freedom and Independence LCSs was accepted in December 2014. Although Lockheed submitted improvements including vertical launch systems, 76 mm guns, and advanced combat systems and sensors, the Navy opted to keep the 57 mm gun, not add a vertical launch system, and chose to add an upgraded 3-D radar. Other changes included installation of an unspecified over-the-horizon missile, Mark 38 25 mm guns, a torpedo countermeasures system, a multifunction towed array system, installation of the SeaRAM launcher, an upgraded countermeasures decoy system, an upgraded electronic warfare system, armor added to vital spaces, and improved signature management. The SSC will focus in SUW and ASW with these additions, as well as retaining all other features of their mission packages; the SSC is not required to perform MCM, which will continue to be handled by the LCS. The vessels will retain a degree of modularity to concentrate on one mission set and will still have mission bays, although they may be reduced. SSC vessels are planned to begin procurement by 2019, and it is being investigated if the enhancements can be added to existing LCS hulls.[47]

Ships

Four Freedom-class LCS ships have been commissioned. Six more are under construction by Lockheed Martin, and three more are on order.

Ship orders and naming history

The Navy originally ordered two Freedom-class littoral combat ships, the lead ship LCS-1 USS Freedom and LCS-3 (even numbers are used for Independence-class littoral combat ships). In March 2009, then-current Secretary of the Navy Donald C. Winter announced that LCS-3 would be named USS Fort Worth. On 29 December 2010, the Navy announced that it would be placing a block-buy order of up to ten additional Freedom-class ships, for a total of 12 ships in the class.[14] On 31 March 2016, the Navy exercised an option under the block-buy contract for one additional Freedom-class vessel; LCS-25 would be the eleventh vessel built under the block-buy contract and the thirteenth overall (Freedom and Fort Worth were built prior to the block-buy order).[16]

On 10 March 2014, the Navy awarded contract options to fund construction of LCS-17 and LCS-19, the seventh and eighth ships in a 10-ship contract.[48] On 1 April 2015 the Navy awarded LCS-21 to Lockheed Martin.[49] As of April 2016, the latest order for Freedom-class LCS ships was LCS-25.[16]

Engine maintenance incidents

As of November 2016, three of four active Freedom-class littoral combat ships have suffered engine maintenance incidents. USS Milwaukee broke down in the Atlantic ocean in December 2015 and had to be towed back to port. Metallic debris was found in the filter system. The cause was traced to a clutch between the gas turbine and diesel engine systems, which failed to disengage as designed while switching from one propulsion system to the other. USS Fort Worth suffered a similar breakdown in the Pacific Ocean in January 2016. Improper procedures used aboard ship caused a set of combining gears—hardware used to transfer power to the ship's water propulsion system—to be operated with insufficient oil. And in July 2016, USS Freedom suffered a seawater leak into one of its two main diesel propulsion systems and had to return to San Diego for seawater decontamination.[50]

Ships in class

Ship Hull Number Laid down Launched Commissioned Status
Freedom LCS-1 2 June 2005 23 September 2006 8 November 2008 Active in service
Fort Worth LCS-3 11 July 2009 7 December 2010 22 September 2012 Active in service
Milwaukee LCS-5 27 October 2011 18 December 2013 21 November 2015 Active in service
Detroit LCS-7 11 August 2012 18 October 2014 22 October 2016 Active in service
Little Rock LCS-9 27 June 2013 18 July 2015 Fitting out
Sioux City LCS-11 19 February 2014 30 January 2016 Fitting out
Wichita LCS-13 9 February 2015 17 September 2016 Fitting out
Billings LCS-15 2 November 2015 Under construction
Indianapolis LCS-17 18 July 2016 Under construction
St. Louis[51] LCS-19 Under construction
Minneapolis/St. Paul[52] LCS-21 On order
Cooperstown LCS-23 On order
Marinette LCS-25 On order

Surface Combat Ship

In 2012, Lockheed renamed the SCS to match GD's Multi-Mission Combatant term and revealed that the full capabilities, such as Aegis, would only be available on a stretched 3,500 ton hull.[53]

Lockheed has also been working on a trimmed down version of the Freedom combat system to offer on the international market for smaller patrol vessels.[54] This Multi-Mission Combat Ship adds in phased-array radar and a vertical launch system on a smaller hull with a smaller crew size, at the cost of removing the high speed gas turbines and one third of the mission module area.[55]

Saudi Arabia

Lockheed Martin has offered an Aegis Combat System-equipped variant for national missile defense radar picket use to a number of Persian Gulf states.[56][57]

The Surface Combat Ship was offered to Saudi Arabia as part of a 2011 arms deal.[58][59] The total cost for the eight ships was reported to be as much as $5 billion.[60] The Saudi Naval Expansion Program II calls for some $20 billion for new warships, which can include up to 12 Freedom-class ships; the Saudis have not looked to purchase Austal's Independence-class ship. The Saudis, as well as other potential foreign buyers, want permanent weapons capabilities built into the ship rather than interchangeable mission packages. Another potential ship under evaluation was the Arleigh Burke-class destroyer; the Freedom class would be outfitted with vertical missile launchers and the SPY-1F radar, a smaller and lighter but shorter range version of Arleigh Burke's SPY-1D. A decision between the ships would be based on the desire for a large-hulled ship with a large missile defense system or a larger number of small-hulled multi-mission ships.[61]

In October 2015, Saudi Arabia requested the sale of four Freedom-class ships to update its eastern fleet in a potential $11.25 billion deal. The multi-mission surface combatant (MMSC) variant does away with the LCS modular mission package ability and the forward two mission bays, but keeps the aft mission bay with a stern ramp. The requirement for an Aegis combat system was dropped for cost reasons and the ships will instead feature the TRS-4D AESA air search radar. Unlike the Flight 0 Freedom, the MMSC features two 8-cell Mk 41 VLS that can carry 16 SM-2 or 64 ESSMs in total, as well as an OTO Melara 76 mm main gun, Harpoon Block II anti-ship missiles, torpedoes, and the SeaRAM. It will also have an MH-60R helicopter, ASW sonar suites, and the Link 16 data-link for interoperability with regional U.S. forces.[56][57][62]

In the book series "Divided we Fall", in the second book "Burning Nation" by Trent Ready, which is based on near future civil war. 4 Freedom Class ships, Freedom, Fort Worth, Milwaukee, and Detroit all ships destroy the town of Lewiston, Idaho.

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