Research becomes a totally immersing experience

Two passengers--a pilot and a scientist --just fit in the Johnson Sea Link's pressure hull, a clear acrylic sphere 5 inches (13 cm) thick, and slightly less than 58 inches (1.5 m) in diameter. Divers wriggle in through an overhead hatch only 18.5 inches (47 cm) wide. During a three- to four-hour dive, things can really warm up. Acrylic is a good insulator, and heat from electronic equipment and the divers' bodies builds up in the cabin.

The Johnson Sea Link dives in the Bahamas, scouting cliffs down to depths of 3000 feet (914 m). Researchers observe marine life by peering through the thick acrylic sphere or through video cameras, and collect specimens using vacuum "slurpers" for delicate ones, jars that close after animals float or swim in, and robot-arms that scoop up rocks and hard-bodied organisms.

Click here to see a short animation of a dive in a submersible much like the Johnson Sea-Link.

The Harbor Branch Oceanographic Institution in Ft. Pierce, Florida, owns and operates two Johnson Sea Link diving craft. Each submersible, carrying a pilot, two scientists, and a technician, conducts about two hundred dives all over the world every year.

Specifications for the Johnson Sea-Link

Size      	length    23.6 ft (7.2 m)
          	height    10.9 ft (3.1 m)
          	beam       8.3 ft (2.5 m)

Speed     	up to 1 knot, highly maneuverable

Gear       	lights, still and video cameras, manipulator arms,
          	suction devices, plankton samplers

Dive time 	usually less than 4 hours, life support back-up for 20

Missions  	mid- and deep-water observation, photography, dump-site
          	inspections, sea-floor sampling, searches and
          	recoveries, underwater archeology

Inventor  	Edwin Albert Link (1904-1981)

Additional submersible and submarine links

Ocean Planet Exhibition Floorplan

gene carl feldman ( (301) 286-9428
Judith Gradwohl, Smithsonian Institution (Curator/Ocean Planet)