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X-Craft / Littoral Surface Craft-Experimental (LSC(X))
Fast Sea Frame / Sea Fighter (FSF 1)

The Navy and Marine Corps will research advanced hull forms, cutting edge propulsion, and material and modular payload technologies for use in a littoral support role. Demonstration efforts are underway on several different vessels, predominantly catamaran designs. The Navy needs to expand this work and look at additional hull designs in order to support future decisions on LCS. The lifting body will be used to provide low speed stability for the craft, allowing an increase in the operational envelope for helicopter operations and potentially for small craft deployment and retrieval. Develop a fluid drag reduction system leading to the improvement of ship speed, improved fuel economy, and reduced air pollution.

The X-Craft was designed to demonstrate to the US and other navies the versatility of a very high speed, high payload capability vessel which can cross oceans quickly, and operate in shallow coastal waters on missions which include mine counter measures and antisubmarine warfare.

In 2003 Landing Support Craft-Experimental (LSC(X)) initiated development of a lifting body design for X-Craft. The Littoral Surface Craft-Experimental LSC(X) was developed by the Office of Naval Research and christened Fast Sea Frame Sea Fighter (FSF 1) on 5 February 2005. The X-Craft transformational program is a high-speed, aluminum catamaran consisting of an advanced hull geometry, designed to give the craft speeds of 50 knots or more. Initially, she will be used by ONR for purposes of hydrodynamic experimentation and as a test bed for Hull, Mechanical, and Electrical (HME) concepts for the Navy's new class of warship, Littoral Combat Ship (LCS).

X-Craft is the first vessel that the Navy has designed specifically as a "sea frame," decoupling hull, mechanical and electrical (HM&E) systems from the mission packages and allowing for a true "plug and fight" mission module capability. Mission flexibility will be demonstrated through interchangeable "mission modules" (standard twenty-foot containers) housed in the X-Craft's large mission bay. The mission bay will hold up to twelve containers, each with its own dedicated service panel, permitting rapid reconfiguration of the vessel to support a variety of potential missions including battle force protection, mine countermeasures, anti-submarine warfare, amphibious assault support, and logistics/humanitarian support.

A multi-purpose stern ramp, with direct access to the mission bay, will allow X-Craft to launch and recover manned and unmanned surface and sub-surface vehicles up to the size of an 11-meter rigid-hull inflatable boat (RHIB) while underway. From its dual spot flight deck, X-Craft will be able to simultaneously operate two H-60 type helicopters (and/or unmanned aerial vehicles (UAVs)). A prototype Night Vision Goggle (NVG) compatible lighting suite will be installed on the flight deck to facilitate NVG-assisted night landings.

Sea Fighter will conduct exercises in support of risk reduction for the Navy's Littoral Combat Ship (LCS) as an "LCS surrogate." Following the exercises, Sea Fighter may be upgraded with weapons and additional electronic equipment. Ultimately, Sea Fighter may be commissioned as an operational Navy ship.

With a design displacement of approximately 1,100 long tons, the X-Craft is of flexible design for spiral technology insertion. The vessel measures approximately 73 meters in length and 22 meters in breadth.

The X-Craft is designed to achieve speeds of 50 knots (109F ambient, 96F seawater temp) in the "Combat Loading" Condition. "Combat Load" Condition is the Light Ship Loading Condition plus150 tons of payload and adequate fuel and stores to operate for 5 hours at 50 knots and 5 days at loiter speed (12 knots).

The X-Craft has a maximum speed of at least 50 knots (40 knots in Sea State 4). It is self-deployable (4000 nautical miles unrefueled). The structure of the vessel is all aluminium with propulsion by waterjets driven by gas turbines for high speed operation and diesel engines for lower speed loitering. Sea Fighter is powered by a combined diesel or gas turbine (CODOG) engine plant outfitted with two MTU 595 diesel engines and two General Electric LM2500 gas turbines. The diesels will primarily power the ship during long-range cruising speeds, while the gas turbines will enable the sea fighter to travel at least 50 knots in calm seas and more than 40 knots in sea state four.

The vessel has been designed for simplicity of construction and operation. Sea Fighter is the first vessel that the Navy has designed specifically as a "sea frame," decoupling hull, mechanical and electrical (HM&E) systems from the mission packages and allowing for a true "plug and fight" mission module capability. Access to the main payload deck is via a large lift down from the flight deck or over folding ramps at the stern.

The vessel's Mission Module Bay is capable of fully supporting simultaneously two or three mission packages designed for the Navy's littoral combat support. Sea Fighter's mission flexibility will be demonstrated through interchangeable "mission modules" (standard twenty foot containers) housed in Sea Fighter's large Mission Bay. The Mission Bay is capable of housing twelve containers, permitting the vessel to be quickly reconfigured to support a variety of potential missions, including battle force protection, mine counter-measures, anti-submarine warfare, amphibious assault support and humanitarian support. A multi-purpose Stern Ramp allows Sea Fighter to launch and recover manned and unmanned surface and sub-surface vehicles up to the size of an 11 meter Rigid-Hull Inflatable Boat (RHIB).

The flush upper deck has a landing area for helicopters, which can also be refuelled with the craft underway. The X-Craft's deck has two helicopter landing spots capable of handling a variety of aircraft up to the size of the H-60-series helicopter.

The ship will have a crew of 26 comprised of four Navy officers and 12 enlisted Sailors working alongside a Coast Guard officer and nine Coast Guard enlisted personnel. As Sea Fighter has been designed for operation with minimum manning, all crew members will be expected to cross-qualify in other areas of responsibility aboard the ship. The small crew will be responsible for all operations and basic maintenance, requiring a significant shift in the normal levels of manning currently used to accomplish various missions and tasks.

The ship has been designed to support a mixed-gender crew. The plankowning crew is made up of five officers and 21 enlisted. While all of them are male, that doesn't mean men will always man the ship. There are a large number of restroom facilities on board, so there's the capability of having separate small bunkrooms for women.

Sea Fighter also will be among the first U.S. Navy ships to employ "paperless" navigation through the use of the Sperry Marine Electronic Charting and Display Information System (ECDIS) and Voyage Management System (VMS). Typically, the ship will operate with just three watchstanders and one roving patrol to monitor and configure engineering systems. This reduced manning will be supported by a level of automation and sophisticated monitoring of systems and equipment previously absent on US Navy ships.

The design is the result of two years research into fuel efficient catamaran hulls giving a very comfortable ride at high speed in moderate sea states. The US Navy's requirement is for the X-Craft to remain fully operational in sea state 4 at 40 knots. Model tests on the hull form have shown that this condition can easily be met and in fact the craft can remain fully operational well into sea state 5. Previous catamarans have normally been designed for high volume, low weight cargoes, such as cars and passengers. In the case of the X-Craft the design philosophy has been geared to high weights of payload and fuel.

The US Navy took delivery of its newest experimental ship, Sea Fighter (FSF 1), at Naval Station Everett, WA in early July 2005. The craft was initially planned to be delivered fully operational not later than June 2004. In order to meet this delivery requirement, the Government negotiated on a sole source basis with Titan Corporation, San Diego CA as prime contractor / systems integrator. Titan had conducted concept exploration and design for this project under two previous contracts beginning in 1998. As a part of its overall integration responsibilities, Titan finalized the X-craft design and, subject to Navy review, conduct competitive selection of the actual shipyard subcontractor.

In September 2002 the United States Navy's Office of Naval Research in Washington DC has chose Titan Corporation of San Diego, California and Nigel Gee and Associates Ltd of Southampton, England to design a new vessel for the US Navy known as the X-Craft.

The US joint venture shipyard of WA-based Austal Ships was short-listed to build the X-Craft. Prime contractorTitan Systems Corporation selected Austal USA as one of five shipyards to participate in the final tender round, which closed early in 2003.

On February 25, 2003, the Office of Naval Research awarded Titan a $59.9 million contract to develop and build the Navy's X-Craft. Work will be performed in Whidbey Island, Wash. (60%), and San Diego, Calif. (40%), and is expected to be completed by October 2004. This contract modification was procured under a justification and approval, dated Oct. 3, 2002.

On February 25, 2003, Titan announced that it is awarding to Nichols Bros. Boat Builders, Inc., a subcontract to provide hull, mechanical, and electrical ship systems for the U.S. Navy's new X-Craft. This award to Nichols Bros. completes an RFI and RFP effort initiated by Titan less than six months earlier. Nichols Bros. Boat Builders, headquartered in Freeland, Washington, specializes in the building of high-speed catamarans and other vessels.

The X-Craft NG427 configuration was designed by United Kingdom-based Nigel Gee and Associates Ltd. The company is a full service design office with 40 employees offering the full range of design capability from Concept Design through to Detailed Shop Floor drawings. In April 2003 Nigel Gee and Associates Ltd, specialists in the design of high speed, innovative mono and multi-hull vessels was acquired by British Maritime Technology Ltd (BMT). BMT is a leading, multi-disciplinary engineering and technology consultancy, specialising in design, design support, risk and contract management and marine surveying, principally in the defence, energy, environment, insurance and transportation sectors.

The new X-Craft high-speed catamaran is powered by MTU 16V 595 engines and GE LM 2500 gas turbines. MTU is providing the integrated propulsion system for the X-Craft. MTU also delivered the modules for the LM2500. The ship's monitoring and control system is MTU's modern MCS5 Type 2 and RCS 5 system. In addition, the ship's electric power supply will be generated by four diesel generator-sets with MTU Series 60 diesel engines. As a system integrator, MTU delivered the main X-Craft propulsion components, marking it the first application of the MTU Series 595 diesel engines in a CODOG configuration for the US Navy. Two well-proven MTU 16V 595 TE90 diesel engines and two GE LM2500 gas turbines are used in a COmbined Diesel Or Gas turbine (CODOG) configuration with a corresponding gearbox, propelling the X-Craft with four waterjets to speeds of more than 50 knots.

Rolls-Royce announced 27 March 2003 that its Kamewa waterjets have been selected for X-Craft, an experimental high-speed aluminum catamaran. Under the contract, awarded by prime contractor The Titan Corporation, four high-efficiency Rolls-Royce Kamewa 125 SII waterjets will accommodate 50.4MW of power driving the vessel to speeds of up to 50 knots while offering greater maneuverability. The installation of two or more independent units makes sideways movement possible, simplifying operations and berthing. Mixed-flow type pumps used in Rolls-Royce Kamewa waterjets provide higher than 90 percent efficiency ratings.

The Navy christened the experimental X-Craft "Sea Fighter" and designated it as the first Fast Sea Frame, on Feb. 5, 2005 during a ceremony at Nichols Bros. Boat Builders, Whidbey Island, WA. Rep. Duncan Hunter, chairman of the House Armed Services Committee, delivered the principal address while his wife, Lynne Hunter, served as the ship's sponsor.

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Page last modified: 07-07-2011 13:01:18 ZULU