For the Coast Guard and its sister sea-services, the art of naval ship design and construction is crucial to mission success. Working closely with the American shipbuilding industrial base, as well as completing due diligence research, world-wide, into the capabilities of comparable vessels, the Coast Guard’s naval engineers and acquisition professionals help to develop surface platforms that meet the needs of the service, into the 21st century. The process of building an advanced ship, such as the National Security Cutter, is one that marries time-honored traditions and lessons learned from centuries of naval architecture, with state-of-the-market technologies that deliver the mission capabilities demanded of today’s complex operational environment.
Unlike aircraft or automotive manufacturing, where many more or less identical platforms are produced, ships typically are built in series (that is, one at a time). There is little or no prototyping in shipbuilding, beyond some laboratory work with advanced hull forms or other structures. A new aircraft design may have been built and flown many times before actual first article production begins. A prototype aircraft rarely is delivered to the customer as an operational asset. In shipbuilding, the first-in-class (a series built to the same basic design) often serves as the class prototype, as well as the first article delivered for operational service.
A first-in-class ship is constructed directly from designs or drawings that are maturing as building continues. Because of the complexity of these processes, first-of-class ships may take between three and six years to complete—from contract award to delivery. Lessons are being learned and applied as the ship is being built and with each subsequent hull constructed in the class. There may be significant hull, mechanical and electrical design or architectural variations from one number to the next within a class of ships.
Today’s larger shipyards are equipped to erect ships in individual assemblies, which contain decks stacked within huge sections of the ship’s outer hull. The assemblies are built upside down (because welding with gravity is more efficient than working against it) at large assembly halls, away from the waterfront. There, the assemblies are outfitted with piping, ventilation ducts and other sub-assemblies and equipment. In certain sections of the ship, these assemblies are stacked together in what are called grand blocks. The completed assemblies and grand blocks are then brought down to the ship’s keel (laid at a site along the waterfront) where the ship is assembled, or erected, and welded together.
Simplified, the sequence of events consists of: