The Virginia (SSN-774)-class submarine construction program is proceeding on a schedule consistent with the master schedule established in 1993, and is essentially on budget, considering inflation and material cost adjustments. The lead ship of the class is approximately 75% complete (as of July 2002) with cost performance on track to achieve a significant reduction in acquisition cost compared to the Seawolf (SSN-21). All material to support the construction schedule of all four ships is available or on order. This successful performance has its origins in the concurrent engineering design process called Design Build.
Design Build involves all of the stakeholders (designers, constructors, suppliers, operators, maintainers, and approval authorities) as active participants in the design process. Thus, the design is tailored to optimize the construction process, to account for the suppliers' equipment, and to incorporate Navy operational and maintenance experience. These stakeholders are involved from the beginning, when the design concepts are being developed in the team meetings, rather than as review agents after the design is developed. In this way, a high-quality design is created for the most efficient build, operation, and maintenance processes.
The Virginia program's predecessor, the Seawolf program, was planned to be a 29-ship class. The end of the Cold War, however, and post-Cold War Defense-budget constraints, could not support the cost of a full class. Thus, the Virginia program was conceived to meet a new threat environment and to provide an affordable class of attack submarines that would replace the aging Los Angeles (SSN-688)-class boats.
In September 1998, the Navy awarded Electric Boat (EB) a construction contract for the first four ships of the Virginia class, to be produced between EB and Newport News Shipbuilding, now Northrop Grumman Newport News (NGNN). This production of nuclear-powered submarines is possible because the two shipyards share the same culture, commitment, and capabilities. The teaming arrangement between the two companies was formalized in February 1997. This agreement was structured to evenly share the construction workload and fee. Each shipyard will produce the same sections for each ship, except for the nuclear area, which is alternated. This division of work enables each shipyard to be specialized on the same sections and yet retain nuclear-powered submarine experience at both shipyards. Final outfitting, final assembly, test, and delivery is alternated between each shipyard. Thus, sections of all four boats are being constructed at both shipyards, and the first and third boats will be joined, tested, and delivered to the Navy at EB, while the second and fourth boats will be joined, tested, and delivered to the Navy at NGNN.
By sharing key responsibilities for building the first four boats, both shipyards will leverage technology, expertise, equipment, purchasing power, and manpower to provide savings to the Navy. The motivation for this partnership is simple: low build rates for submarines cannot affordably sustain two nuclear-qualified shipbuilders in a competitive acquisition process. The EB/NGNN teaming agreement maintains both companies as submarine construction yards at a much lower cost.
Partners in Construction
Construction is being performed at three main facilities: EB's hull manufacturing and outfitting facility at Quonset Point, Rhode Island; EB's Groton, Connecticut shipyard; and the NGNN shipyard in Newport News, Virginia. The Quonset Point facility fabricates pressure hull cylinders for shipment in support of module construction at the Virginia shipyard. The Quonset Point facility also constructs all EB-assigned modules for shipment to the Groton shipyard for EB-delivered ships, where final integration, assembly, outfit, and test will be accomplished. Quonset Point also performs module/section construction for those modules/sections that EB builds for NGNN-delivered ships. NGNN manufactures its assigned modules and transports them to Groton for Electric Boat-delivered ships. The command-and-control system module will be completed for all ships at the Groton facility, where all combat system components will be integrated and tested prior to insertion into the EB-delivered ships, and prior to shipment to NGNN for the NGNN-delivered ships.
To facilitate construction at both EB and NGNN, an engineering/construction support team from each shipyard resides in the other. The teams provide construction information to assist the design agent who produces the construction drawings, and advise their own shipyard and the other coproduction shipyard during the construction process. The NGNN team at EB reviews and approves all construction drawings. They participate as members of the Design Build teams, imparting NGNN construction experience into the design, and gain a detailed understanding of the products that will be used by NGNN to build and test different sections of the ship. The EB team at NGNN performs design agent support functions (EB is the sole design agent) locally to provide drawing interpretation, correct drawing errors, and provide approval for deviation requests submitted by NGNN. Both teams are liaisons between the shipyards to identify and expedite problem resolution, and to assure proper interface between the products of each shipyard.
In addition, this close teaming relationship has resulted in a sharing of "tricks of the trade." For example, EB has shared its extensive fixturing technology with NGNN, which formerly used fixturing to a much lesser degree, and NGNN has shared its extensive photogrammetry processes with EB for optical targeting to locate equipment.
Material acquisition responsibility has been divided between EB and NNGN to maximize the advantage of capability, business volume, and contracts at each facility. Factors that were considered in assigning procurement responsibility include:
- Distinct technical advantage in one area
- Location of equipment with respect to the construction location of the particular module
- Economies of scale of procuring this material with similar equipment for other programs
For example, NGNN procures far more standard valves than EB in the normal course of business. NGNN therefore procures all standard valves for the program. EB's Quonset Point facility, with its automated hull fabrication capability, is the common source for all the hull cylinders for each ship. A majority of the large castings for the ship will be made at NGNN, because that facility has a large foundry.
A Plan for Success
The complexity of a nuclear-powered submarine drives the number of detailed work elements into the millions. A thorough initial schedule is easier to follow. By 1993, the master working schedule was developed with more than 150,000 elements for the design, build, test, and validation effort. The computer tools provide an easier way to prepare and update the commitment lists, but several hours still are set aside every day for the EB program manager to review the status of every commitment and take the necessary action to ensure completion on time. Almost every week, the complete commitment list is reviewed internally at EB and externally with the Navy and key suppliers.
No single metric can reflect the success of a program, but the degree to which a high-quality design is completed at the start of construction is a strong indicator. An incomplete design at the start of construction increases risk and the likelihood that changes will be necessary. Design changes after construction has started have created significant cost increases in the past. The Navy and EB therefore dedicated themselves to a stable design baseline, to the completion of all ship arrangements, and to increasing the number of drawings issued by the start of construction compared to previous classes. As a result, the Virginia class had 50% of the construction drawings issued before start of construction compared to 6% for the Seawolf. Electronically, the ship was completely arranged to the lowest level of component in a three-dimensional mockup environment prior to the start of construction. This virtual arrangement could be animated into a construction-and-assembly plan sequence ensuring the design could be built efficiently and affordably. As a result, the Virginia has required dramatically fewer (by an order of magnitude) design changes during construction.
Underlying processes, tools, and manning levels are the three basic tenets of success:
- Establish detailed plans and schedules early, make decisions as planned, get buy-in from individuals for each piece of the work they must complete, and doggedly manage the detailed tasks to ensure timely completion.
- Establish cost and schedule procedures in which cost reduction concepts are encouraged and developed, cost and schedule impacts are evaluated in all decisions, and cost and schedule performance becomes ingrained in the culture through continuous monitoring and reporting systems. This effort applies across all phases of the life of a ship: design, material and equipment acquisition, construction, test and validation, operation, life-cycle maintenance, and eventual disposal.
- Get the right people from the appropriate organizations involved with the designers in time to provide the designers with the best knowledge for cost-effective design.
These points cannot be overemphasized. Aggressive execution of these tenets has minimized delinquent work and resulted in an atmosphere in which high quality timely completions and cost-effective actions are the norm.
Modular Construction
Modular construction allows most of the fabrication to take place in a shop environment with full access to all areas of the module or section. The first scheduled hull section for the lead ship was 98% outfitted prior to joining to adjacent sections, and represented a weight of 1,100 tons. The same hull section for the second ship achieved a completion level of 99%. These completion levels represent the highest degree of modularity achieved on any major warship construction. The Virginia will be 85% complete when the pressure hull is completed, compared to 58% for the Seawolf. Work remaining after the pressure hull is complete includes interconnections between sections, final outfitting, system test, transfer of system operational control to the Navy, sea trials, and delivery. Thus, the Virginia has achieved the highest level of overall ship completion that can be achieved prior to pressure hull completion.
Better Drawings, Fewer Changes
The quality of the construction drawings developed on the Virginia class is much improved over the Seawolf class. A true measure of construction drawing quality is the number of construction problems requiring changes to the drawings. As of July 2002 at an equivalent 75% complete labor on the Virginia vs. the Seawolf, 88% fewer construction drawing changes have been requested by the construction trades at both EB and NGNN shipyards. It is interesting to note that the Seawolf performance is not atypical of major combatant lead ship experience. NGNN, which was the lead design agent for the SSN-688 class, had the same performance level on the lead ship, Los Angeles. EB also had the same performance level on their lead SSN-688 ship, the Philadelphia, which was completed just seven months later. Thus, the Virginia Design Build process truly is a break from the past.
The overall cost performance of the program is within 14% of the original budget. Of that 14%, approximately 13% can be attributed to higher-than-expected costs of material, equipment and labor, escalating because of low-rate production without the funding to buy material in economic order quantities. Thus, the controllable cost performance is within 1% of the original budget. Cost reduction is a continuing effort, and performance is measured and reported constantly. All phases of the life of the ship from initial design through disposal are evaluated for cost-saving measures.
In summary, the Virginia-class design process, organization, systems, and tools are enabling an efficient ship construction process. In addition, the people from all of the involved organizations, their leadership, and their resolve to make it work through diligent commitment tracking and aggressive problem resolution, are the key to the successful performance.
Mr. Kowenhoven is a staff engineer in the Virginia program and has held various engineering and management positions at Electric Boat over the past 40 years. Mr. Harris is Vice President of Programs for Electric Boat and has held various engineering and management positions at Electric Boat and in the Merchant Marine.