After a yearlong assessment of its fleet, the U.S Navy on Friday said it needs to grow to 355 ships and increase the number of attack submarines from 48 to 66, which could mean substantial gains for military families and Electric Boat and its 450-plus suppliers in the state.

The 2016 Force Structure Assessment began in January and assessed the security and defense requirements for future naval forces. Its findings were released Friday at the Pentagon in Arlington, Va.

The assessment recommended a 355-ship fleet — up from the current 272 — including 12 carriers, 104 large surface combatants, 52 small surface combatants, 38 amphibious ships and 66 attack submarines. The current requirement for attack submarines is 48 and has not been increased since 2004.

“The Navy’s new assessment is confirmation of the clear reality that a larger fleet is both necessary and vital to the nation’s security,” U.S. Rep. Joe Courtney, D-2nd District, said in a news release.

A larger fleet also would bring relief to local military families coping with longer, more frequent deployments and shorter stays at home, he said. Deployments that used to last six months have been extended to seven months; stays home that used to last 18 months have fallen to 12 months, Courtney said.

"A lot is being asked of (military families) to keep up with the demand for submarines. And enlarging the fleet at some point is not just about shipbuilding. It's about sailors and officers and their families," he said.

Increasing the submarine fleet from 48 to 66 ships ultimately could demand that ships be built at a faster rate, Courtney said. Military think tank groups in Washington, D.C., have discussed whether to boost production from two to three submarines per year, Courtney said. The added production may be needed to increase the fleet because the Navy must also replace aging submarines.

The assessment also helps confirm Groton's military value, Courtney said. "The Navy's investing in Groton, so I think its military value, given the strategic underpinnings of this report, is very much validated," he said.

Earlier this month, Congress passed a $618.7 billion defense policy bill that members of Connecticut's congressional delegation called a victory for the state.

The bill includes $5 billion for the two Virginia-class attack submarines a year that Electric Boat builds with Newport News Shipbuilding in Virginia. Another $1.9 billion would go toward building a new fleet of 12 ballistic missile submarines, known as the Columbia-class program, to replace the current fleet of Ohio-class ballistic submarines.

The long-awaited assessment spoke to future investment, as well.

“It should not be assumed that this force level is the desired force size the Navy would pursue if resources were not a constraint,” the assessment’s executive summary said. “Rather, this is the level that balances an acceptable level of warfighting risk to our equipment and personnel against available resources and achieves a force size that can reasonably achieve success.”

Navy leadership expressed confidence in the Navy force assessment plan.

"To continue to protect America and defend our strategic interests around the world, all while continuing the counterterrorism fight and appropriately competing with a growing China and resurgent Russia, our Navy must continue to grow," Secretary of the Navy Ray Mabus said in a prepared statement. "All of the analysis done to date, inside and outside of the Navy, recognizes, as we have for nearly the last eight years, the need for a larger fleet."

U.S. Sens. Richard Blumenthal and Chris Murphy issued a joint statement praising the commitment to future investment in submarines.

"We are proud that Connecticut's skilled defense manufacturing workforce produces the most dominant undersea force in the world," the senators said in a news release. "Supporting our submarine fleet is not only critical to naval preparedness, but to jobs and economic growth in our state."

The Navy has worked with the defense industry and Congress to reverse the decline in shipbuilding that occurred from 2001 to 2009, Mabus said. Keeping that momentum and maintaining cost-saving measures will be crucial to ensuring the Navy achieves its recommended fleet size, he said.

Courtney said he's particularly pleased about plans for a larger attack submarine force.

"This makes sustaining the two (submarines) a year build rate as we also build the Columbia-Class SSBN a national imperative, while also taking advantage of every possible opportunity to add to that build rate," he said.

The last assessment of the Navy fleet was done in 2012 and updated in 2014.

d.straszheim@theday.com