Scuba ships are indicated for the east central and 
Gulf of Mexico regions because of their utility to 
scientific divers and the physiographic character 
of the regions. In both regions it is frequently neces- 
sary to travel 10 or 15 miles offshore to be able to 
dive to depths exceeding 50 feet. Here, the use of 
a ship, rather than a habitat, to support divers is 
indicated. 
MANNED UNDERSEA ACTIVITIES WORKSHOP 
Responding to a recommendation of the National 
Academy of Science (NAS)-National Academy of 
Engineering (NAE) Committee Advisory to 
NOAA, a joint study by NAS Ocean Affairs Board 
and the NAE Marine Board was conducted to re- 
view and assess civil manned undersea activities. 
The NAS-NAE assembled a group of approximately 
60 persons (about one-third each from Government, 
academia, and industry) in a workshop to answer 
the following seven questions: 
—What should be the current and projected na- 
tional civil goals for undersea science and tech- 
nology requiring the presence of man, either 
directly or indirectly, both in the short and 
long term? 
—wWhat are, and what should be, the roles of 
the U.S. Government, academia, and industry 
with regard to the development of this undersea 
science and technology to support the national 
civil goals? 
MANNED UNDERSEA ACTIVITY IN PERSPECTIVE 
Manned undersea activity is not a new concept. 
For more than 200 years, man has salvaged wrecks 
and has built structures under water. Shortly after 
World War Il, self-contained underwater breathing 
apparatus (scuba) became available, providing an 
inexpensive and simple capability for underwater 
activity. Underwater salvage and construction divers 
were soon joined by scientific and recreational 
divers. 
By the early 1960's the first practical deep sub- 
mersibles were in use in the United States and in 
France. The development of deep submergence ve- 
hicles (DSV's) provided the needed platforms for 
extending manned undersea activity beyond practi- 
cal skin diving depths. 
The rapid growth of skin diving and submersible 
activity since World War Il was fueled by military 
needs and scientific and industrialized work capa- 
bilities. During the past few years, industry has con- 
tinued to work in deeper water, farther from shore, 
and in more hostile environments. 
EXECUTIVE SUMMARY 
22 
—What are the ways, including alternatives to 
the presence of man, to achieve these goals; 
and if man is primary, what are the alternate 
modes for his presence? 
—What are the criteria by which programs to 
fulfill these goals can be evaluated? 
—What limits the effectiveness of man in under- 
water science and technology programs? (Le., 
institutional, technological, physiological, etc.) 
—What are critical scientific and technical de- 
velopments which may provide further break- 
throughs? 
—What programs are necessary and feasible for 
significant manned undersea activities under aus- 
tere, constrained, and ideal budget situations? 
The workshop was co-chaired by Dr. Alfred Kiel 
of the Massachusetts Institute of Technology and 
Dr. Adrian Richards of Lehigh University and held 
from October 17 through October 21, 1972. Par- 
ticipants were carefully selected to obtain balanced 
representation by organizations, background, and 
orientation toward manned undersea activities. By 
this means, it was the intention of NAS-NAE to 
insure an unbiased report specific and realistic 
enough to be acted upon. The Executive Summary 
section of the NAS-NAE study entitled “Civil 
Manned Undersea Activity: An Assessment” is pre- 
sented below in its entirety. 
Today the number of operational DSV’s is con- 
siderably less than in the late 1960's. Only one 
company in the United States produces DSV’s regu- 
larly, and only five commercial firms operate DSV’s. 
Most submersibles are in semiretirement. The U.S. 
Navy with 11 DSV’s is the largest world owner of 
these craft. 
In the diving community, advances are still being 
made. But dives deeper than 40 meters, made on 
a frequent or prolonged diving basis, still pose com- 
plex physiological and technical problems that must 
be solved. At present, experimental diving activities 
belong in the hands of the professional divers. A 
few experimental saturated dives have been made 
to depths of over 600 meters but the costs of 
operating at these depths are high and conse- 
quently industry is developing less costly unmanned 
underwater work systems, or shirtsleeve-environ- 
ment systems such as those for petroleum subsea 
completion systems. 
In the past decade, operational sea floor habitats 
have been developed. The Navy’s SEALAB, GE’s 
