San Antonio class. However, any plan to upgrade these vessels, is, as of December 2022, currently unfunded. Viability of the LCS program: the USN operates two classes of littoral combat ships (LCS), the and the , which with their extensive list of problems are considered by many in Congress and the Department of Defense to be expensive failures and should be prematurely retired from service. While these vessels cannot fulfil all the roles of a JSS, they were supposed to be the navy's premier multi-mission vessels, and if they are removed from service would create a gap in certain capabilities for the Navy. Next-Generation Logistics Ship (NGLS) Program: NGLS is quite an important project for the USN as not only will it responsible for the Navy's next auxiliary ships but it marks a fundamental shift in the recent design philosophy that "bigger is better", which has seen most other classes of ships grow in size. The USN's emerging doctrine of anti-access/area-denial (A2/AD) aims to create a "no-go zone" for an opposing force in times of conflict built upon more distributed fleets with a reduced proportion of larger ships and an increased proportion of smaller ships, thus lessening the risk posed by concentrated attacks on a relatively small number of large, high-value targets. Vessels in the NGLS program will be part of that objective. Currently, the USN is constructing the new TAO (oilers), traditional large - and expensive - vessels at more than $700 million per ship, built at a rate of just one ship per year. The NGLS program would instead deliver a new class of smaller ships that would be less expensive and faster to construct yet meet the requirements for refuelling, rearming and resupply operations. However, these vessels, described as "medium-sized" ships, are not intended to replace but to supplement these new vessels and existing classes such as the Fast combat support ship, with an emphasis on operations in contested and littoral environments deemed too high a risk for larger vessels.The Navy's five-year shipbuilding plan for financial years 2023–FY2027 outlines the procurement of the first NGLS in 2026 at a cost of $150 million and the second in 2027 at $156 million, each around the fifth of the cost of a John Lewis-class vessel. It is not yet determined how many vessels will be constructed but the 30-year plan commencing 2023 proposes at least a dozen or so