wet chamber has a full-diameter door providing 
access for small submersibles. Support systems 
planned include comprehensive data gathering, 
evaluating, and monitoring devices and a computer 
system to allow simulation of a large open ocean 
area. Preprogramming of entire experimental runs 
and automatic gas control will be possible. Use of 
the chambers will concentrate on diver equipment 
development, evaluation, and training. 
One industrial high pressure simulation facility, 
a three chamber complex, will go into operation in 
early 1969 at Annapolis, Maryland. It is a 
1,500-foot facility with one water filled chamber. 
Support systems include a gas storage and distribu- 
tion system which makes possible charging any 
selected chamber with air or other gas mixtures. 
Decompression may be accomplished manually or 
automatically along a selected decompression 
curve. 
The largest currently operational hyperbaric 
facility is at Duke University, Durham, North 
Carolina. Its five interconnected vessels have more 
than 9,000 cubic feet of volume. The largest, a 
20-foot sphere containing an operating theater, is 
rated to 225 feet of seawater equivalent pressure. 
Three of the vessels, one a wet chamber, are rated 
to 1,000 feet. 
The University of Maryland and Ohio State 
University are building hyperbaric facilities with 
1,000-foot capacity. A facility with a 1,600-foot 
seawater rating is nearing completion at the 
University of Pennsylvania in Philadelphia. 
Although there is widespread interest among 
the academic and industrial communities in ocean 
related research and hyperbaric medicine, the 
substantial first cost and operating expense deter 
many. Also, because the field is relatively new, 
hyperbaric projects tend to be uncertain invest- 
ments. More experience is required before the 
pattern for using these facilities is established with 
confidence. 
2. Future Needs 
Research will be needed to better understand 
physiological phenomena, especially with the an- 
ticipated increase in depth of routine operations. 
In determining the limits of human endurance, 
experiments under closely controlled conditions 
are essential so immediate corrective action can be 
taken. Jn situ testing to determine human limits is 
VI1-80 
unacceptable. In addition, much work remains to 
determine optimum decompression schedules. This 
is especially important since deep diving opera- 
tions require several days of decompression. 
Military activities also will be expanding human 
capability limits. Most marked needs will be in 
training and equipment evaluation. Industry is 
building additional hyperbaric facilities, but the 
main emphasis probably will be on exploiting and 
consolidating diving capabilities to depths around 
1,000 feet. Test facilities with wet and dry 
chambers will be needed to permit experimental 
diving to 2,000 feet. 
C. Ocean Test Ranges 
1. Current Situation 
Simulation facilities cannot reproduce certain 
parameters of the ocean environment as the 
long-term fouling effects of marine life and the 
acoustic effects of size. Test and evaluation of 
systems effectiveness during missions requiring 
mobility, search, and use of acoustics generally 
must be performed in ocean test ranges. Noise 
quieting projects require anechoic characteristics, 
not yet satisfactorily simulated in a chamber. 
Many pieces of equipment which work well in a 
laboratory pressure tank fail in the hostile, un- 
known undersea environment. Part of the simula- 
tion problem lies in insufficient understanding of 
which parameters must be reproduced. In addi- 
tion, simply providing temperature and salinity 
control increases costs greatly. Thus, it is often 
desirable to use the sea environment for equip- 
ment development. 
The Navy owns all but two of the operational 
ocean engineering ranges (Makai Range in Hawaii 
and the University of Southern California range on 
Santa Catalina Island, California). Industry assists 
the Navy in much of its range operations. 
The Navy’s Atlantic Undersea Test and Evalua- 
tion Center (AUTEC), with principal facilities at 
Andros Island, Bahamas, and St. Croix, Virgin 
Islands, is conducting limited testing. 
When fully completed in 1970, the center will 
have a wide range of capabilities to test undersea 
vehicles, weapons, and weapon systems. Range 
functions will include operational evaluation of 
advanced weapon systems and components, meas- 
urement of submarine noise and other target 
parameters, evaluation of antisubmarine warfare 
