Navy and industry say capacity is there to boost fleet numbers.

The U.S Navy's path to expanding its fleet to over 350 ships will not be easy, but it is possible, officials said. The Navy has performed its duties at the same level of operational tempo since 9/11 with significantly fewer ships, Vice Chief of Naval Operations Adm. William Moran said in January. That means the ships it deploys are making longer and more frequent trips, promoting wear and tear and raising maintenance costs.

In 2001, the Navy was operating 316 ships, "and we're still operating in the same tempo, with 274 ships," he said.

The Navy has been unable to fully fund its needs for several years due to budget uncertainty, he added. "We're lucky in any given year to have had 90 percent funding."

If the service's budget allocation continues along this trend, the Navy could be deploying at sea fewer than 90 ships within a few years, he warned. "We haven't deployed less than 90 ships in the last 15 years, on a daily basis."

The service leader for PEO submarine said that the Navy is working to develop a revised 30-year shipbuilding plan since the force structure assessment raised the requirement from 48 nuclear-powered attack submarines to 66.

"So we went from managing a trough where we were below 48 SSNs later in the 2020s, to immediately being in a trough under 66," Rear Adm. Michael Jabaley said.

It is possible to build that quickly, he noted, saying that the Navy delivered up to six Los Angeles-class submarines in one year in the 1980s, while also building the Ohio-class ballistic missile submarine.

"The question is: At what point do you need to start building more facilities, hiring more people?" he said, adding that shipbuilders are already expanding to handle the increased demand signal wrought by the...