GAO Critical of US Navy Saying Submarines Are Idle Due to Shipyard Logjam

GAO says backlog means submarines are idle too long or cannot be decommissioned (USN)

Published Sep 4, 2026 7:26 PM by The Maritime Executive

Too many of the U.S. Navy's attack submarines are sitting idle across shipyards awaiting maintenance and decommissioning, according to a new report by the Government Accountability Office (GAO). The report highlights the challenges, saying it is impacting operational readiness and costing billions of dollars in lost productivity.

GAO is once again putting the U.S. Navy in the spotlight with its latest audit report focusing on attack submarines. It asserts that over the past decade, idle time has become the “buzzword” owing to submarines' inability to secure yard space for maintenance. For boats that have reached end of life and are awaiting decommissioning, it similarly asserts that shipyards are unable to start the process due to lack of capacity.

In the report, GAO is highlighting that the Navy has lost more than 15,000 operational days due to maintenance delays and idle time on active submarines over the last 10 years. The delays have resulted in an estimated $3.4 billion in costs to sustain crews and submarines that provided no operational capability. Another $3.1 billion is being swallowed due to decommissioning delays.

The U.S. Navy operates a fleet of 44 attack submarines. The 20 Los Angeles class and 24 Virginia class boats typically enter an extensive depot maintenance period, often lasting 24 to 36 months at a certain period during their life cycle.

Currently, the four public naval shipyards, Portsmouth, Norfolk, Puget Sound, and Pearl Harbor, as well as two private yards, General Dynamics and Huntington Ingalls Industries, are responsible not only for building new submarines but also for providing depot maintenance and decommissioning work for the 44 boats.

The shipyards are operating under extreme pressure, a reality that has seen the Navy’s submarine maintenance backlog persist since 2008, the outcome of which is 15,000 operational days being lost and $3.4 billion wasted, say the GAO, due to the shipyards' inability to undertake the maintenance. The situation has gotten worse over the past decade, with the Navy only managing to complete about 11 percent of depot maintenance on time at public yards.

The Navy’s predicament is being exacerbated by submarines awaiting decommissioning that must sit idle because shipyards cannot commence the process, which includes availing dry docking capacity to defuel the boats' nuclear reactors. On this, the U.S is performing spectacularly poorly, with the situation only bound to worsen, says the GAO. Over the past five years, the Navy incurred 2,216 days of idle time on seven submarines awaiting decommissioning, with costs amounting to more than $480 million.

GAO is highlighting that without mitigation, 15 submarines are expected to enter inactive idle time over the next four years. Over the period, the Navy is set to incur more than 14,000 days of inactive idle time and $3.1 billion in costs.

The Los Angeles-class submarine USS Pasadena (SSN-752) is currently a poster child of the quagmire facing the Navy in terms of decommissioning. The boat entered inactive idle status in January last year and is not expected to be moved into Norfolk Naval for decommissioning until November 2028, whopping 1,414 days, due to shipyard capacity constraints. Though idle, the sub remains fully crewed. For the four years it will remain in inactive idle status, Pasadena is expected to incur $300 million in costs.

“The U.S. Navy has not fully evaluated alternative options to more efficiently decommission attack submarines and develop and implement an inactivation plan that could allow them to reduce inactive idle time for crews and save billions,” stated GAO.

The report, which is prepared for Congress, seeks to explore the extent to which the U.S. Navy has effectively maintained its attack submarine fleet and what it is doing to mitigate challenges. Apart from maintenance and decommissioning, the report also shows the Navy is grappling with delays in the building of new boats, the effect of which is fewer boats for deployment.  

Construction of the new Virginia-class submarines is a case in point. As of June 2025, only one boat is being built per year against a target of two. Though the Navy received delivery of two boats of the class last year, both were over three years late.