ARLINGTON, Va. — U.S. Navy officials are worried the service in the 2030s may have just enough nuclear-armed submarines to meet operational requirements — but no extras in case one becomes unavailable.

So the sea service is looking at steps to both extend the service lives of some outgoing Ohio-class ballistic missile submarines and hasten the delivery of new Columbia-class submarines.

Rear Adm. Scott Pappano, the program executive officer for strategic submarines, said the submarine force is required to have 10 SSBNs ready to go to sea at any given time. These submarines go on long deployments, tasked with lurking undetected in the depths of the oceans and carrying the nuclear missiles the United States hopes to never launch.

As the Ohios age out of the fleet, though, and the new Columbias come online, there are times when the fleet is expected to have 10 or fewer boats available, Pappano said Nov. 1 at the Naval Submarine League’s annual conference here.

To address that problem, Pappano said the Navy is working to accelerate the delivery of new submarines.

The Navy developed an integrated enterprise plan with industry, Rear Adm. Doug Perry, the director of undersea warfare on the chief of naval operations’ staff, said at the conference. The plan, which requires buy-in from the Defense Department, ship construction yards and lower-tier suppliers, could accelerate the delivery schedule for boats 2 through 12 by as much as six months, Perry said.

Pappano added that the Navy hopes to buy boats 3 through 7 through a block-buy contract, meant to allow the Navy and prime contractor General Dynamics Electric Boat to buy material more cost-effectively. As global supply chain woes have slowed the delivery of long lead time parts, Pappano said the block buy would allow these parts to be put on contract earlier in the process.

Pappano said accelerating ship construction timelines by six months would eliminate all instances of the available SSBN inventory falling below 10 in the future force projections.

Still, that leaves no extra submarines in case of unforeseen incidents. So, as many as five Ohio SSBNs may go through an 18-month maintenance and modernization period to give them three additional years of operations at sea — offering the fleet a greater buffer, Pappano said.

Operating the Ohios even longer

The Navy already extended the service life for the entire Ohio class out to 42 years, and the class cannot be extended again. But the Navy can assess each individual hull as it nears the end of its life and look for ones that still have plenty of nuclear fuel remaining and whose hulls are in good shape.

Submarines that meet these criteria could be put into a so-called pre-inactivation restricted availability, where targeted maintenance work would be done to keep the boats and their combat systems in top shape for three more years of service life.

Subs that aren’t good candidates for this life extension would be used to benefit the rest of the fleet, either by undergoing destructive testing to learn more about the condition of the boats or to be cannibalized so their parts can be used on the boats that are extended.

Navy officials first publicly discussed the idea of extending the lives of select Ohio boats at Sub League’s 2020 conference. In comments then and since, leadership has couched the decision to consider these life extensions as a hedge against any problems with Columbia construction. The Navy bought its first Columbia SSBN in fiscal 2021, will buy the second in FY24, and will then buy the remaining ships at a one-a-year rate from FY26 through FY35, asking industry to build at a pace not seen since the Cold War.

But Pappano raised a number of other concerns over the ship inventory the Navy is eyeing for next decade.

“The riskiest period during the transition is in the 2030s, as the Columbias come online and Ohios go offline,” he told Defense News at the conference.

Much like with cars, he said, submarines are most prone to problems at two times, when they’re new and may reveal production line mistakes, and when they’re old and components start to fail. The 2030s will be “a critical period with just new ships and just old ships.”

And, he said, the Navy will upgrade its nuclear-tipped missiles in the 2030s, moving to the Trident D5 Life Extension II payload. In the 2036 to 2039 timeframe, Pappano said, the Navy will need to use both an Ohio-class submarine and a Columbia-class submarine to test the new missile and ensure they’re interoperable with both classes of ships — meaning one or two submarines will be pulled from operations to participate in sea trials.

Asked how much it would cost to fix up a handful of Ohios, Pappano didn’t provide a dollar amount but said it’s “not cost prohibitive to go do that” and would be on par with any other 18-month maintenance and modernization availability for a submarine.

Perry added that cost would be one factor in deciding how many ships to put through the life extension work. Shipyard availability would be another; the Navy’s shipyards are already struggling to improve their performance and get boats out of maintenance on time, and Perry said he doesn’t want this life extension project to upend the work already being done.

Pappano said he believed the service would extend at least two or three boats, and as many as five.

For the first potential ship, USS Alaska in 2029, Pappano said he’s eyeing a decision in fiscal 2026 to ensure enough time to buy long-lead material, allow the shipyard to plan and work the modernization availability into the budget.

Megan Eckstein is the naval warfare reporter at Defense News. She has covered military news since 2009, with a focus on U.S. Navy and Marine Corps operations, acquisition programs and budgets. She has reported from four geographic fleets and is happiest when she’s filing stories from a ship. Megan is a University of Maryland alumna.

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