With the Russian Navy placing an increased emphasis on its submarine fleet, the United States has taken a number of steps meant to curb the Russian advance throughout the Arctic and Northern Atlantic. But longstanding issues caused by budgetary delays, sequestration, and repeated cuts continue to haunt the force.

The re-establishment of the once defunct 2nd Fleet, for instance, will provide America’s eastern seaboard with a valuable defense against the encroachment of Russian submarines — particularly after the Kremlin announced training exercises that placed Russian attack subs just outside a number of U.S. Naval ports last year. The Russians claimed to have operated undetected, and the United States has opted to remain tight-lipped about those claims — perhaps because they don’t want to show their hand, or possibly because the Russian subs really did manage the feat. In either regard, the threat seems clear: Russia’s surface fleet may be a relic of the once-mighty Soviet Navy, but their sub force is modern, capable, and a potential threat to American security.

That’s where America’s massive fleet of around 50 nuclear attack submarines come in. No submarines in the world are said to be stealthier or more capable when it comes to the cat and mouse games played beneath the surface of the ocean… that is, when they’re actually out at sea. According to a new report created by the Government Accountability Office, America’s attack submarines have experienced historically long waits not only for repairs, but even for routine maintenance.

Our analysis found that the primary driver affecting attack submarines are delays in completing depot maintenance,” read the report. “For example, of the 10,363 total days of lost time since fiscal year 2008, 8,472 (82 percent) were due to depot maintenance delays.”

Seawolf-class fast-attack submarine USS Connecticut (SSN 22) departs Submarine Base New London. U.S. Navy photo by Mr. John Narewski (RELEASED)

Those figures are significant enough to warrant further discussions. In the past ten years, U.S. Navy attack submarines have spent a combined total of 8,472 days sitting idle as they awaited routine maintenance. A math wiz would tell you that 8,472 days comes out to a bit more than 23 years worth of submarine operations lost to maintenance delays over the past decade. Though, the GAO estimates that those submarines may have only been conducting actual operations during 1,891 days of that 8,000+ day window.

“While demand for our undersea fleet and its unique capabilities continues to rise as reflected in the 2016 Force Structure Assessment, delays in maintaining our existing fleet are exacerbating the growing shortfall in our submarine force structure,” Rep. Joe Courtney (D-Conn.), ranking member on the House Armed Services Seapower and Projection Forces Subcommittee, said of the report.

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“This report makes clear that the Navy must do more to fully utilize the capacity of our private shipyards to reduce the backlog in submarine repair work — something I have repeatedly urged the Navy to act on,” Courtney added.

The issue isn’t just about time lost, however. The U.S. Navy’s costs don’t diminish while it’s attack subs spend weeks or even months waiting in line for their spot in the dry dock. As a result, the Navy has spent about $1.5 billion on the support costs of submarines that couldn’t go to sea over the past ten years. For frame of reference, that’s more than half the cost of just building an entirely new Virginia-class submarine — the most advanced sub in the Navy’s fleet. What’s worse, however, is that despite the influx of cash under the Trump administration, the state of America’s submarine maintenance doesn’t appear to be improving quickly.

The Virginia-class attack submarine Minnesota (SSN 783) is under construction at Huntington Ingalls Newport News Shipbuilding, Nov. 1, 2012. (U.S. Navy photo courtesy of Newport News Shipbuilding/Released)

The Navy expects the maintenance backlogs at the public shipyards to continue. We estimate that, as a result of these backlogs, the Navy will incur approximately $266 million in operating and support costs in Fiscal year 2018 constant dollars for idle submarines from Fiscal year 2018 through Fiscal year 2023, as well as additional depot maintenance delays,” the report predicts.

Even the ways in which the Navy has sought to alleviate these backlogs has caused issues within the civilian shipyard industry. The GAO does note that the Navy made the decision to begin farming attack sub maintenance out to private shipyards in an effort to alleviate the delays, but because the Navy opts to do so with no set procedure or predictable schedule, they’ve made it nearly impossible for the civilian sector to keep pace with the need for workers.

Although the Navy has shifted about 8 million man-hours in attack submarine maintenance to private shipyards over the past five years, it has done so sporadically, having decided to do so in some cases only after experiencing lengthy periods of idle time,” read the report. “According to private shipyard officials, the sporadic shifts in workload have resulted in repair workload gaps that have disrupted private shipyard workforce, performance, and capital investment—creating costs that are ultimately borne in part by the Navy.”

For now, the Navy has agreed to conduct a thorough review “of submarine maintenance requirements and impacts across both the public and private shipyards,” but no corrective action has been laid out thus far.