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Shipyard problems continue to plague US Navy carrier and sub availability

Warship Technology: October 2020 Shipyard problems continue to plague US Navy


The Government Accountability Office (GAO) in the US has reported on serious issues at US Navy-run shipyards that are causing significant delays to maintenance of aircraft carriers and nuclear-powered submarines.


The Senate Armed Services Committee, in a report accompanying a bill for the National Defense Authorization Act for Fiscal Year 2019, included a provision for GAO to review the performance of US Navy shipyards.


The GAO evaluated the extent to which the US Navy:


  • completed maintenance at its shipyards on time on aircraft carriers and submarines in fiscal years 2015 through 2019
  • identified the main factors leading to maintenance delays, and
  • has addressed the main factors affecting any delays in that maintenance.


The four shipyards in question are Norfolk Naval Shipyard in Virginia, Pearl Harbor Naval Shipyard and Intermediate Maintenance Facility in Hawaii, Portsmouth Naval Shipyard in Maine, and Puget Sound Naval Shipyard and Intermediate Maintenance Facility in Washington. Their role is to maintain the readiness of aircraft carriers and submarines required for military operations.


Since 2015, the GAO has issued no less than 20 reports and testimonies examining US Navy maintenance challenges, shipyard workforce and capital investment, ship crewing, scheduling, and force structure.


In an August 2020 report, the GAO said the US Navy’s quartet of shipyards completed 38 out of 51 (75%) maintenance periods for aircraft carriers and submarines late in the period FY2015 through FY2019. These delays equate to 7,424 days of maintenance delays in total. For each maintenance period completed late, the shipyards averaged 113 days late for aircraft carriers and 225 days late for submarines.


The GAO found that unplanned work and workforce factors – such as shipyard workforce performance and capacity (having enough people to undertake the work) – were the main factors causing maintenance delays for carriers and submarines.


The US Navy frequently cited both factors as contributing to maintenance delays. Unplanned work – work identified after finalising maintenance plans – contributed to more than 4,100 days of maintenance delays.