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Two articles that the sub fans here will find interesting:
U.S. Sub Contract Awards Expected Dec. 22
http://www.defensenews.com/story.php?i=3872168&c=AME&s=SEA
By christopher p. cavas
Published: 19 Dec 16:55 EST (21:55 GMT)
U.S submariners and their shipbuilders could get an early Christmas present Monday, when the U.S. Navy is expected to announce the award of $14 billion in construction contracts.
The new submarines are the next eight ships of the SSN 774 Virginia class of nuclear attack subs.
General Dynamics Electric Boat is the prime contractor for the Virginia-class program, with construction split equally between Northrop Grumman Shipbuilding's Newport News, Va., shipyard and GD's facilities at Quonset Point, R.I., and Groton, Conn.
The new submarines collectively are referred to as Block III. Funding for the first of the Block III boats, the North Dakota (SSN 784), was included in the 2009 defense budget. The Navy plans to ask for one more submarine in 2010 and two subs in 2011, 2012 and 2013 to complete the new group.
The Block III submarines will be the first to feature the new Virginia Payload Tube (VPT), a large-diameter launch tube based on the reconfigured former ballistic missile launch tubes on the Ohio-class SSGN cruise missile submarines. The VPTs, which can each hold six Tomahawk cruise missiles, replace 12 separate Tomahawk launch tubes built into earlier versions of the class.
The Block III subs also will incorporate the Large Aperture Bow Array, an improved arrangement of sonar and underwater listening devices.
More than a hundred other design changes - many developed under "design for affordability" guidelines intended to reduce costs or improve construction time - are integrated into the new ships.
The new contracts cap a year that saw two U.S. submarines from the same class commissioned in the same year for the first time since 1995. The Newport News-assembled North Carolina was commissioned on May 3 and the New Hampshire, completed at Groton, was commissioned on Oct. 25. General Dynamics also held a keel ceremony for the Missouri on Sept. 27 at Quonset Point, while Newport News hosted a keel ceremony for the New Mexico on Dec. 13.
Delivery of the North Dakota is scheduled for 2015.
Block III: The Changes
The most obvious change is the switch from 12 vertical launch tubes, to 12 missiles in 2 tubes that use technology from the Ohio Class special forces/ strike SSGN program. The Virginia’s hull has a smaller cross-section than the converted ballistic missile SSGNs, so the “6-shooters” will be shorter and a bit wider. Nevertheless, they will share a great deal of common technology, allowing innovations on either platform to be incorporated into the other submarine class during major maintenance milestones. Net savings are about $8 million to program baseline costs.
The other big change you can see in the above diagram is switching from an air-backed sonar sphere to a water-backed Large Aperture Bow (LAB) array. Eliminating the hundreds of SUBSAFE penetrations that help maintain required pressure in the air-backed sonar sphere will save approximately $11 million per hull, and begins with the FY 2012 boats (SSNs 787-788).
The LAB Array has 2 primary components: the passive array, which will provide improved performance, and a medium-frequency active array. It utilizes transducers from the SSN-21 Seawolf Class that are that are designed to last the life of the hull. This is rather par for the course, as the Virginia Class’ was created in the 1990s to incorporate key elements of the $4 billion Seawolf Class submarine technologies into a cheaper boat.
The SUBSAFE eliminations, plus the life-of-the-hull transducers, will help to reduce the submarines’ life cycle costs as well by removing moving parts that require maintenance, eliminating possible points of failure and repair, and removing the need for transducer replacements in drydock.
The bow redesign is not limited to these changes, however, and includes 25 associated redesign efforts. These are estimated to reduce construction costs by another $20 million per hull beginning with the FY 2012 submarine.
With the $19 million ($11 + 8 ) from the LAB array and Vertical Payload, and the $20 million from the associated changes, General Dynamics is $39 million toward the $200 million baseline costs goal of “2 for 4 in 12”. While the changes themselves will begin with the FY 2009 ship, the savings are targeted at FY 2012 because of the learning curve required as part of the switch. Recent discussions concerning an earlier shift to 2 submarines per year would result in faster production of the Block III submarines, but would be unlikely to make a huge difference to that learning curve.
Dec 12/08:
General Dynamics Electric Boat Corp. in Groton, CT received a $16.8 million cost-plus-fixed-fee material order to fund the Block III Common Weapon Launcher (CWL) design, and includes the total scope associated with the vendor portion of the inboard electronics design as well as the scope required for in-house (Electric Boat) tasks. The CWL will sit in the Block III bow’s “six shooter” holes, and is so named because that space can be used to launch a wide variety of items besides UGM-109 Tomahawk cruise missiles; aerial UAVs and underwater UUVs are the most obvious.
GDEB services will include engineering support, Engineering Development Model (EDM) hardware, continued development of the CWL for use with SSN 784 VPT, development of interface documents, and defining changes to support interfaces to the Weapon Control and Payload Tube Control Panels. Work will be performed in Manassas, VA, and is expected to be complete by 2013. This contract was not competitively procured by the supervisor of Shipbuilding Conversion and Repair in Groton CT (N00024-09-C-2101).
Lockheed Martin Maritime Systems and Sensors in Manassas, VA received a $38.3 million modification to previously awarded contract (N00024-04-C-6207) for engineering services in support of the Acoustic – Rapid Commercial off The Shelf (A-RCI) program. The 550,000 additional engineering services hours will be used on TacLAN tasking related to Special Operations support, and to complete the new “BSY-2 Wrap Around Antenna (WAA),” which is listed as being a Virginia Class sonar.
DID requested clarification, and got it. BSY-2 is a Seawolf class system only. WAA is the Wide Aperture Array, and on the SSN-774 Virginia Class it evolved to the L-WAA (Lightweight Wide Aperture Array). The Virginia Class Block III bow has been redesigned to save money beginning with SSN 784; it will use the Large Aperture Bow (LAB) Array.
It turns out that the DefenseLINK release should read “technology insertions for the USS Jimmy Carter’s [SSN 23 Seawolf Class] BSY-2 WAA, and USS North Carolina [SSN 777 Virginia Class] LWAA TI-08 integration.” The exact work involved is technology insertion, integration, and modernization on USS Jimmy Carter and USS North Carolina, as well as the completion of the existing TI-08 effort and the Virginia Class Block III TI-10 Large Aperture Bow (LAB) Array effort for SSN 784.
Work will be performed in Manassas, VA (90%) and Syracuse, NY (10%) and is expected to be complete by June 2009. This contract was not competitively procured by US Naval Sea Systems Command.
