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	Director, Operational Test & Evaluation
FY97 Annual Report

NEW ATTACK SUBMARINE (NSSN)

	Navy ACAT ID Program 30 systems Total program cost (TY$) $67034M Average unit cost (TY$) $2110M Full-rate production 1QFY07 Prime Contractor General Dynamics Electric Boat Division Newport News Shipbuilding Lockheed Martin Federal Systems - (Combat System)

SYSTEM DESCRIPTION & CONTRIBUTION TO JOINT VISION 2010

The New Attack Submarine (NSSN) is intended to be an affordable submarine which will support Joint Vision 2010 and the strategy of maintaining maritime superiority. NSSN is to have a broad range of missions. These include Covert Strike Warfare, Anti-Submarine Warfare, Covert Intelligence Collection/Surveillance, Covert Indication and Warning and Electronic Warfare, Anti-Surface Ship Warfare, Special Warfare, Covert Mine Warfare, and Battle Group Support. NSSN will use advanced technology and commercial off-the-shelf (COTS) equipment to reduce acquisition and life cycle costs while retaining mission effectiveness.

NSSN will be capable of launching MK 48 ADCAP torpedoes, mines, and Tomahawk missiles, supporting dominant maneuver as well as full-dimensional protection for afloat forces. Its sonar capability will be similar to SEAWOLF's, and it will have an improved combat control system. The external communications system will be an improvement over SEAWOLF and legacy systems, providing full, high data rate interoperability with U.S. and allied forces. These characteristics will provide intelligence and strike capabilities to support the Joint Force Commander in precision engagement. NSSN will maintain a level of stealth equivalent to SEAWOLF (SSN 21) class submarines.

The Milestone I DAB approved NSSN to enter Phase I in August 1994. For Milestone II, COMOPTEVFOR conducted a very aggressive and thorough early operational assessment (EOA) of NSSN, concluding that NSSN was potentially operationally effective. The EOA identified one high risk area and a number of areas of moderate risk , which merited close attention by the program manager. These risks were discussed in the classified version of the FY96 Annual Report. The Program Office and Navy sponsor cooperated fully with COMOPTEVFOR in this EOA and generally agreed with the findings.

DOT&E recommended and the Secretary of Defense approved a waiver to full-up, system level live fire test of NSSN. DOT&E approved the alternative LFT&E plan submitted in lieu of full-up system level LFT&E in June 1995. The Milestone II DAB approved NSSN to enter Phase II on June 30, 1995.

T&E was consistent with the TEMP.

COMOPTEVFOR reported on the first phase of a continuing operational assessment (OT-IIA) in February 1997. The OA Report found NSSN to be potentially operationally effective and potentially operationally suitable. This OA supported a program review held in February 1997 to approve construction of the lead ship. DOT&E concurred with COMOPTEVFOR's findings. A Vulnerability Assessment Report intended to support the program review was not sufficiently developed, and the program agreed to update it in April 1998. The VAR did not adversely affect the decision. However, the acquisition strategy was not consistent with then existing legislation, so the decision was delayed until October 1997, when the acquisition strategy and anticipated FY98 law revisions were consistent, and the DAE approved acquisition of the first four ships.

A number of systems that will be part of NSSN underwent testing in FY97. TB-29 towed array and the ADCAP Torpedo Block Upgrade III completed OPEVAL in September 1997. The Submarine Advanced Tomahawk Weapons Control System (Sub-ATWCS), Ring-laser Gyro Navigator and Doppler Sonar Velocity Log underwent operational testing as well. A scale model of the propulsor was tested. When USS SEAWOLF went to sea, the following equipment common or similar to NSSN were observed; propulsor, wide aperture array (WAA), impressed current cathodic protection system, and active shaft grounding system.

A study to support the vulnerability assessment of NSSN was begun at Electric Boat Shipyard. This study looks at the shock effects from underwater explosions that could be generated by threat weapons. The vulnerability assessment will also address secondary casualties, cascading damage, and crew impact.

Carried weapon vulnerability assessments continued, with limited developmental testing of instrumented torpedo and missile vehicles.

The January 1997 OA report indicated high risk existed in several programmatic areas, since formal plans or funding didn't exist for the external communications system, the towed array, mines or ASUW missiles. As a result of DoD funding shortfalls, NSSN and supporting programs faced significant down-scoping which could reduce the effectiveness of the submarine. Technical risks were found in high data rate antennas and in other areas addressed in the classified version of this report.

DOT&E concurs with the OA report. Since then, funding has been obtained and a program started for an improved towed array. The Navy has identified and funded a number of technological improvements for insertion into different NSSN hulls as the improvements become available, and is studying others, which will be implemented if funding becomes available. In October 1997, DIA released a new STAR. The impact of this on NSSN performance margin will require additional assessment.

A key concept in NSSN is that risk will be reduced through the use of equipment and concepts developed under the aegis of other programs, such as SSN-21, Submarine External Communications System, Sub-ATWCS, and Acoustic Rapid COTS Insertion (A-RCI). Some of these systems were moderately successful in OPEVALs. Several communications systems components did not perform well in operational assessments. DOT&E is concerned that there may be interoperability problems with external communications components as well. The Acoustic Rapid COTS Insertion system, a phase of which will go into NSSN, has shown some promise, although there are some reliability problems with the first phase which is still in development.

The external communications system continues to evolve. A contract for the system, although projected for FY97, has not yet been awarded. This will continue to be an area of concern, as the NSSN ORD requires interoperability with joint tactical communications and intelligence circuits, and the projected communications suite and requirements for other Navy ships is not firm.

In SITE III shock testing of a scaled down NSSN hull section, the program office discovered some potential vulnerabilities, and made a design change. This is discussed in the classified version of this report. DOT&E considers one of the vulnerabilities to be a potentially serious risk.

The Site III test series provided confidence that the CCSM isolated deck structure and mounting system installed in the NSSN will provide adequate shock isolation protection for commercial-off-the-shelf (COTS) equipment that will form a major part of the NSSN C3I system.

DOT&E has made several contributions to NSSN. Continued emphasis on realistic targets and scenarios for testing has led to a revised operational test program similar to USS SEAWOLF's, with the latest and quietest possible submarine targets. DOT&E's continued concern for holding the line on performance in the face of budget cuts contributed to the Navy's emphasis on maintaining performance of towed arrays and other components and supported the Navy's effort to introduce new technology. DOT&E expressed concern about potential carried weapon shock vulnerability to NSSN management in 1996, and is closely following the analysis.

M&S requires some type of validation. SITE III shock testing produced unexpected results both in the type and extent of shock effects. The NSSN program directed model improvements as a result.

Because of the cooperation of the NSSN program office, early operational tester involvement, including the EOA and OA, was useful to the program manager in validating some risk areas that needed management attention, and so served its purpose. The EOA and OA also provided an independent corroboration of program office statements about progress and potential performance.