VESSEL REVIEW | Atlas – Dry dock to support construction of US Navy's future ballistic missile submarines

US naval shipbuilder General Dynamics Electric Boat (GDEB) has begun operating its newest floating dry dock at its submarine construction facilities in Groton, Connecticut.

The 618- by 140-foot (188- by 43-metre) Atlas was built by Bollinger Shipyards of Louisiana to a concept design by Rhode Island-based naval architecture firm the Bristol Harbor Group.

The drydock will support GDEB's construction and sustainment of the US Navy Columbia-class nuclear-powered ballistic missile submarine (SSBN) program by providing essential dry dock capacity for construction, maintenance, and long-term sustainment. GDEB is the prime contractor on the design and build of the Columbia-class boats, which will replace the ageing Ohio-class SSBNs due to begin to retire from service in 2027.

Facilitating efficient construction and maintenance

As a floating dock, Atlas provides greater flexibility in construction compared to a traditional engraving dock. This attribute is especially important as each of the Columbia-class SSBNs will be composed of multi-deck cylindrical modules that are built separately and then assembled to form the hull.

The dry dock is capable of self-ballasting to compensate for the weight when a heavy load, such as a submarine module, is being rolled onto it. The dock will then travel along the south face of GDEB’s South Yard Assembly Building, where construction of the first Columbia-class boats is underway. The dock can align to either of the building's assembly bays.

To permit this manoeuvre, GDEB constructed an adjacent sinking basin, which required dredging of approximately 900,000 cubic yards (700,000 cubic metres) of sediment.

One of many dedicated facilities for SSBN manufacture

Atlas' delivery last October marked the completion of Bollinger's second contract with GDEB.

In late 2019, Bollinger was selected to construct the 400- by 100-foot (120- by 30-metre), self-ballasting ocean transport barge Holland for GDEB. The barge was delivered on schedule in 2021.

Bollinger is also in the construction phase of a pontoon launcher for GDEB, which will support the construction and launching of the Columbia-class boats.