WASHINGTON -- The U.S. Navy’s next-generation submarine will carry up to 16 Trident ballistic missiles and, in a cost-saving gambit, will take advantage of technologies developed for today’s Ohio-class nuclear-armed vessels and Virginia-class fast attack boats, according to service officials (see GSN, Feb. 4).

The “initial plan” is for “16 tubes, a new-design reactor plant [for propulsion], similar antennas and design to the Trident and the Virginia class submarine, [but with] no advanced torpedo room,” Rear Adm. Joseph Mulloy, the Navy deputy assistant secretary for budget matters, said at a February 14 press conference.

The two-star flag officer briefed reporters on his service’s portion of a $671 billion Pentagon budget request for fiscal 2012, which begins on October 1. Submitted for congressional consideration last week as part of the overall military package, the Navy’s $161 billion spending plan includes $1.07 billion to begin major development of the new submarine.

Reflecting a new Defense Department emphasis on reducing procurement costs, the vessel would essentially be an “improved” version of today’s Ohio-class submarines -- or “SSBNs” -- that also incorporates technologies from the submersible attack platform, Mulloy said.

The strategy for replacing today’s 14 Ohio-class nuclear-capable submarines “is to maximize the re-use of existing Ohio systems and new designs from Virginia class (as applicable), focus on life cycle total ownership cost affordability, and meet the higher standards required for this [submarine] to achieve mission success in a challenging environment,” according to Navy budget documents.

The so-called SSBN(X) is also expected to offer an improvement in stealth capabilities, making it harder for would-be adversaries to detect, according to Mulloy. He did not elaborate.

The chief of naval operations last year rejected a U.S. Strategic Command proposal for the new submarine to feature 20 missile tubes, Global Security Newswire first reported early this month. Strategic Command is a combatant headquarters based in Nebraska that would oversee any U.S. nuclear weapon strikes, given presidential authorization.

Adm. Gary Roughead argued in June that the anticipated global threat at the time the SSBN(X) is fielded -- beginning roughly in 2030 -- would not justify the cost involved in building such a heavily armed submarine.

Today’s Ohio-class submarines each carry 24 Trident ballistic missiles, though the Navy plans to “inactivate” four tubes per boat under the U.S.-Russian New START arms control agreement (see GSN, Sept. 30, 2010). The treaty, which entered into force early this month, caps deployed nuclear warheads at 1,550 and strategic delivery vehicles at 700, with another 100 platforms allowed in reserve.

“While the new Strategic Arms Reduction Treaty (START) recently reduced the number of required SSBN missile tubes from 24 to 20, the Ohio Replacement will be operational in the 2030 to 2080 time frame, well beyond the period considered by START and the Nuclear Posture Review,” Roughead stated in a June 20, 2010, memo reviewed by GSN. “It is prudent to assume a 16-missile tube design approach for the Ohio Replacement … based on recent trends within our nation’s nuclear force strategy.”

The Pentagon-led posture review, completed last April, focused principally on deterrence strategy and forces for the next five to 10 years, a period substantially before the new submarine is to be fielded.

As the Navy’s top officer, Roughead directed his service to “continue to work with [Strategic Command] to comprehensively examine future requirements in the 2030 to 2080 time frame.”

Mulloy’s remarks last week were among the first design details the Navy has released since shepherding plans for the future submarine through a top-level Pentagon review board at a closed-door meeting in December.

A Defense Department spokeswoman last week made available a three-paragraph “Information Paper” documenting the results of the Defense Acquisition Board’s December 9 meeting to review the Navy’s initial design concepts for the Ohio-class replacement vessel.

Pentagon buying czar Ashton Carter, as board chairman, “determined that the program is ready for the technology development phase,” according to the paper, signed by Carter deputy Frank Kendall. During this research-and-development phase, the Navy will develop and design the boat’s “Common Missile Compartment, propulsion plant and supporting ship systems,” the document states.

The missile compartment, jointly procured with the United Kingdom for its own Trident submarines, would package four missile tubes into one set that can be installed -- along with three other sets -- in the vessel for a total of 16 tubes.

Mulloy said the review board approved the service’s basic approach to designing the submarine, though many details will still have to be sorted out during the upcoming developmental effort.

“We know general specs,” the officer said. “It must be able to take care of a crew and have oxygen, but the specifics of the power and weight and layout of all that will now happen as a result of this money being in the '12 budget. We can rapidly move down that path.”

In a handwritten note at the bottom of his Information Paper, Kendall added that the submarine’s milestone approval was “subject to revision and additional review prior to the release” of a fiscal 2012 research-and-development design contract.

Although the Kendall document was hand-dated December 28, 2010, the Naval Sea Systems Command announced early this month that the SSBN(X) effort could not enter into the technology development phase until January 10.

“The Defense Acquisition Board endorsed replacing the current 14 Ohio-class ballistic missile submarines as they reach the end of their service life with 12 Ohio replacement submarines,” each featuring 16 missile tubes measuring 87 inches in diameter, the naval command said.

During the upcoming developmental phase, military “warfighting requirements will be refined to meet operational and affordability goals,” states the release. “Design, prototyping, and technology development efforts will continue to ensure sufficient technological maturity for lead-ship procurement in 2019.”

It could take another eight years or so to build and field the first such submarine, according to the Defense Department.

A February 2 decision memorandum, signed by Carter, includes a Pentagon cost estimate of $347.2 billion for the submarine program, the independent newsletter Inside the Pentagon reported last week. The figure includes anticipated expenditures for the development, procurement and operation of the new submarine fleet over its 50-year life span.

The price tag is the Pentagon’s first publicly known total cost projection for the SSBN(X) and substantially exceeds earlier independent estimates, the publication reported.

In the decision memo, Carter reportedly acknowledged that the Defense Department’s Nuclear Posture Review last year called for a possible reduction from today’s 14 Ohio-class submarines to a 12-vessel fleet by the end of this decade.

“I understand, however, that changes to the future security environment could create the possibility for a lower or higher required number of [Ohio replacement] submarines,” states the Carter memo, according to a review of the document by Inside the Pentagon. “Analysis of the potential to change the number of submarines will be made as the program progresses.”