R/V SEWARD JOHNSON lengthening midbody addition results in added general oceanographic capabilities while retaining undersea vehicle support features

The Research Vessel SEWARD JOHNSON, constructed in 1984 by Atlantic Marine Inc. (Jacksonville, Fl.) and commissioned in 1985, has functioned primarily as a purpose-built submersible support vessel, a task which she performed routinely for a decade. With the commissioning of a remotely operated vehicle (ROV) system for submersible rescue, which included an integral launcher/winch assembly and a control van, it became apparent that valuable deck space currently being used for deployment of scientific instruments would be lost, which prompted an in depth look at the possibility of lengthening the SEWARD JOHNSON. A feasibility study was conducted to determine the optimum size and location on the vessel to insert a midbody module yet retain her “uninspected oceanographic research vessel” status. It was determined that a module could be inserted ahead of the engine room, which would provide increased tankage, berthing, storage, and laboratory and deck space. The New York City based naval architect firm, M. Rosenblatt and Son, Inc., was contracted to generate the necessary drawings and specifications. Atlantic Dry Dock Corp., Jacksonville, Fl. was selected to modify the vessel. An extended yard period was required to complete the lengthening procedure and upgrade and modify numerous original equipment items that were deemed to be antiquated. A dynamic positioning system, new instrumentation, and a heavy duty crane were installed to enhance the vessel´s capabilities. After 18 months of operations, the modified SEWARD JOHNSON has proven herself as an extremely capable general oceanographic vessel in addition to her submersible support capabilities