Recommendations: 
While it is not realistic to presume that any one 
power source will be adequate for all underwater 
requirements, the design, development, testing, 
and certification of each new source is both time 
consuming and expensive. Therefore, it is also 
unrealistic to conceive of a program wherein all 
power sources will be developed simultaneously. A 
more rational approach dictates that development 
efforts be directed initially to low-cost adaptions 
of existing power sources to systems specifically 
designed for the ocean environment. 
Development of compact, deep ocean power 
sources ranging particularly between 50 and 5,000 
kilowatts for deep submergence vehicles and habi- 
tats is most urgent and should receive first priority. 
Engineering criteria, standards, and perform- 
ance and qualification specifications for power 
systems (including components) must be estab- 
lished for nonmilitary underwater applications. 
Applied research and component improvement 
programs must be supported. The development of 
a low-cost 50 kilowatt power source for submer- 
sible operations of several days is an example. 
Fuel cells should receive priority to meet the 10 
to 100 kilowatt demand of small submersibles, a 
requirement that can be met by the DSSV fuel cell 
project if carried out as planned. Development of 
both hydrazine and hydrogen-oxygen systems 
should be supported. Cryogenic underwater tech- 
nology should be emphasized because of its 
potential application in fuel cell and thermal 
conversion systems. In the range for resource 
utilization on the continental shelves, thermal 
conversion systems should receive renewed devel- 
opment support. 
C. External Machinery Systems and Equipment 
The sea environment imposes entirely new 
operational requirements on machinery systems. 
Mechanical and electrical equipment have been 
developed for operation in the atmosphere or in 
the vacuum of space, but the ocean’s high pressure 
and corrosiveness impose more severe demands 
than have been encountered in most previous 
applications. 
Military submarines operate at relatively shal- 
low depths with most machinery systems inside 
the pressure hull and a minimum of equipment 
exposed to the ocean environment. Consequently, 
little undersea component development has been 
directed toward external machinery. Yet small 
submersible hulls generally enclose only the man 
and the electronic equipment, and in unmanned 
systems it is desirable to utilize as little heavy 
pressure-resistant structure as possible. Conse- 
quently, efficient design requires the use of new 
subsystems exposed directly to the ocean environ- 
ment. 
The attempt to use off-the-shelf or slightly 
modified equipment in submersible systems be- 
cause of cost has in many cases proved unwise. 
Few items have worked as planned, and modifica- 
tion has been expensive. The use of off-the-shelf 
equipment in effect has led to in situ testing, often 
a costly and wasteful procedure. A few hours of 
operation without any equipment malfunction is 
the best expected from vehicles in initial stages of 
operation. 
The Circular of Requirements issued in late 
1965 as part of the procurement specification for 
the Deep Submergence Rescue Vehicle (DSRV) 
specified the use of off-the-shelf equipment. But 
many subsystems proposed would not operate 
when tested in the deep environment, requiring 
added efforts to develop, test, and qualify suitable 
equipment for the vehicle. 
Safety and progress in the undersea frontier 
necessitate testing, evaluation, and certification of 
equipment for external operation prior to installa- 
tion. Because the use of equipment exposed to the 
environment promises great rewards in the effi- 
ciency of undersea systems, external machinery 
systems and equipment development should re- 
ceive emphasis in the fundamental technology 
development program. 
1. Power Application 
a. Current Situation A key element of mobile 
undersea platforms will be the propulsion system. 
Neutrally buoyant vehicles may have to have 
mobility in all six degrees of freedom—(1) heave 
(up and down), (2) surge (fore and aft), (3) sway 
(right and left), (4) roll, (5) pitch, and (6) yaw. 
For docking or mating, very precise maneuver- 
ability is required. For many activities speeds of 
five knots or less are acceptable, but in such cases 
as chasing tuna or potential enemy submarines 
much higher forward speeds are needed. 
V1-37 
