The shipyard Huntington Ingalls Industries (HII) confirmed that the future USS Massachusetts (SSN-798), a Virginia-class Block IV nuclear-powered attack submarine of the U.S. Navy, successfully completed its initial sea trials off the coast of Virginia. The SSN-798 will be the 25th submarine of its class to enter service, further consolidating the modernization of the U.S. attack submarine fleet.
The Virginia-class attack submarine program began in the 1990s, in a context marked by the end of the Cold War and the need to redefine the United States’ submarine strategy, in which the Los Angeles class had been the backbone of anti-submarine warfare against the USSR. However, the U.S. Navy required a more versatile, flexible, and cost-effective submarine, capable of operating both in deep ocean and littoral environments, compared to the expensive Seawolf class, of which only three units were built.
Out of that need emerged the Virginia class, conceived as a modular and adaptable design with progressive improvements introduced in each construction block. The first submarine, USS Virginia (SSN-774), was commissioned in 2004. The program is organized into construction blocks, each comprising a series of submarines featuring gradual enhancements in design, sensors, weaponry, and maintenance. The Block IV submarines incorporate optimized maintenance cycles, which increase operational availability.
By December 2024, the U.S. Navy reported progress on the construction of the 27th submarine, reflecting the continuity of the program despite budgetary pressures and the parallel implementation of other major naval development and shipbuilding efforts, such as the new Columbia-class nuclear ballistic missile submarines, which will replace the current Ohio class.
Finally, during the USS Massachusetts’ sea trials, systems including propulsion, dive control, communications, and sensors were successfully tested — a key step prior to delivery. With 27 units in various stages of construction and Block V underway, the U.S. Navy ensures its submarine fleet will maintain technological superiority until the arrival of the SSN(X), the next-generation platform.
Images used for illustrative purposes.
