412 



to repair and modify Sealab III and expects to restart the experiment in the late 

 summer. Sealab III is part of the Man-in-the-Sea phase of the Navy Deep Sub- 

 mergence Systems Project established as a result of the nuclear submarine 

 Thresher loss in 1965. Another part of the project, the Navy's Deep Submergence 

 Search Vehicle now under development, has top priority in testing so that further 

 delay of Sealab III could conceivably occur. 



The Sealab III habitat was specifically designed, fabricated and outfitted 

 by the Navy for use as a sea floor laboratory. Its structure is essentially the same 

 as that of its successful predecessor, Sealab II, although it contains modifications 

 reflecting the experience acquired in earlier ocean work. A 57-foDt long 12-foot 

 diameter cylinder accommodates five teams of aquanauts for successive 12-day 

 periods during the 60-day experiment. The aquanauts will perform tasks in six 

 general areas, namely, oceanography, engineering, construction, salvage, biology 

 and human performance. Sealab III is supported on the surface by the "Elk River", 

 a converted World War II landing ship which provides complete decompression 

 facilities, personnel transfer to and from the habitat, physiological monitoring and 

 medical facilities, storage of equipment and maintenance of communications, in- 

 strumentation and gas sannpling lines. 



The objective of the Sealab III program is to gain knowledge and "know 

 how" pertinent to the adaptation of man to the deep sea environment at ambient 

 pressure. The primary interest of the Defense Department and the Navy in the 

 "Man-in-the-Sea" experiments is to provide a capability for rescue and salvage 

 operations, maintenance of bottom-mounted equipment, use of the continental 

 shelf for military operations associated with, for example, mine defense and 

 amphibious assault. However, this program has vast potential secondary peace- 

 ful uses for the nation. Technology gained in the program will hasten to make 

 possible exploitation of the world's continental shelves for food, minerals and re- 

 creation. By 1970, the U.S. Navy plans to have diver-aquanauts living in advanced 

 sea habitations on the continental shelves for 30 days or more without coming to 

 the surface. The depth capability of the aquanauts will ultimately be extended from 

 the average 600-foot depths of the shelves down to the as yet unknown physiological 

 limits of man. Forty aquanauts , five teams of eight men each, including civilian 

 scientists, will occupy the underwater habitat alternately for 12-day periods for a 

 total of 60 days. Connmander M. Scott Carpenter, the former astronaut who was 

 team leader for 30 days during the 1965 Sealab II operation, is serving as senior 

 aquanaut directing the activities of the five team leaders, although he will no 

 longer participate in actual diving because of medical considerations. A number 

 of U.S. Navy activities as well as the Department of Interior's Bureau of Conn- 

 mercial Fisheries and the Philadelphia General Hospital are involved in developing 

 the tasks the aquanauts will perform. 



In carrying out the project's physical oceanography work, devices will be 

 installed in the ocean floor including current meters, thermographs, a tide gauge, 

 an underwater "weather station", temperature recorders, bio-luminescence meters, 

 a radiance meter, and salinity meters. Aquanauts from the Bureau of Commercial 

 Fisheries will conduct work in the areas of marine biology and ecology. Porpoises 

 and sea lions will also be used as they were in Sealab II to demonstrate the feasibility' 

 of aiding lost aquanauts, delivering tools, messages and other obiects. 



