JOHNSON-SEA-LINK I & II, HARBOR BRANCH manned submersibles devoted primarily to research in the marine sciences, are classed and certified to a maximum operating depth of 3,000 feet by the American Bureau of Shipping (ABS). The forward five-inch thick acrylic sphere accommodates the pilot and an observer at "one atmosphere," and allows panoramic visibility. A second crew member and another observer occupy the after observation chamber where a video monitor and side view ports provide forward and side observation. The evolution of specialized equipment such as manipulator arms, suction devices, and rotary plankton samplers has made it possible for crewmen to accomplish almost any work from within the subs that once was done only by divers. The JOHNSON-SEA-LINK submersibles are further outfitted with active sonar, laser aimed still and broadcast quality video cameras, and HARBOR BRANCH-developed xenon arc lights. The arc lights approximate sunlight, illuminating underwater scenes in true color and near daylight conditions, even in the darkest seas. These sophisticated and highly maneuverable free swimming submersibles have been in operation since 1971 and 1975. Maintained and operated by experienced and expert pilots and crews, they are further supported by in-house ocean engineers. Typical applications include benthic and/or mid-water observations, photo/video documentation and collection of organisms; dump site inspections and monitoring; punch and box coring; search and recovery; bottom surveys; photogrammetric surveys; archaeological site documentation and recovery; and environmental impact studies. General Capabilities 1. Operate at any depth from the surface to 3000 fsw (not to exceed 3300 fsw actual bottom depth) at a speed of 0-1 knot, and remain submerged for periods of up to approximately 4 hours (120 hours under emergency conditions). 2. Carry one observer in the acrylic pilot sphere, one observer in the aft observation chamber (AOC), and various internal and/or external instrumentation and tools. 3. Maneuver within close proximity of slopes or other bottom topography. 4. Hover at neutral buoyancy and/or rest on the bottom to perform scientific and engineering tasks, including still and video photography. 5. Use its manipulator and specialized tools to deploy various scientific instruments and to collect samples. 6. Provide a limited amount of electric and hydraulic power for instruments and equipment not normally part of the submersible. 7. Offer data logging and display capabilities with standard sensors including temperature, conductivity, and depth.