In order to alleviate these problems, some basic 
studies are being made in tool development; a few 
examples are discussed below. 
The hammer undoubtedly would have devel- 
oped along very different lines had the human race 
evolved in a medium relatively as heavy and 
viscous as water. Considerable energy is wasted 
under water during the travel of the hammerhead 
and shaft prior to impact. An efficient manual 
underwater striking tool could employ a heavy 
streamlined weight traveling a relatively short 
distance along a straight guide. Pneumatic ham- 
mers accomplish the same effect with shorter 
strokes. 
Explosive studs fired from a hand gun to 
penetrate the hull plates of sunken vessels have 
been known since before World War II. Such tools 
still are somewhat crude, but the possible variants 
warrant further development. By clustering six or 
eight stud guns around the periphery of a circular 
plate with a lifting eye in the center, a very solid 
lifting pad can be attached quickly to almost any 
sunken metal structure. When injecting breathing 
gas or air into a compartment for buoyancy, a 
hollow stud driven through the compartment wall 
can serve as the through-hull penetrator. 
Underwater welding techniques must consider 
the chilling effect of the surrounding water. The 
problem is especially evident with some high- 
yield-strength steels. Methods currently are under 
development to weld in a gas-filled compartment 
erected around the work area. 
Steel can be cut by an electric oxygen torch 
with a hollow electrode. After an arc has been 
struck, oxygen is forced through the center of the 
electrode to burn the hot steel. 
Sonic search devices may be carried by divers in 
poor visibility. A system presently undergoing test 
employs a continuous transmission, frequency 
modulated (CTFM) signal. A hand-held device 
emits an acoustic signal; echoes from obstructions 
modulate the return signal’s pitch conducted to 
the diver’s earphones. A high pitch indicates an 
obstruction at close range. 
Because of high cost, the device is not used 
extensively. Greater effectiveness and lower price 
should result from volume production and compe- 
tition. For many underwater search tasks, a 
wrist-mounted magnetic compass is adequate, but 
not reliable near a wreck or other large ferrous 
structure. 
VI-SO 
The Naval Underwater Warfare Center has been 
working on a hydrodynamic winch, a salvage lift 
padeye using explosive bolts, a buoyancy transport 
device which can carry objects weighing up to 
1,000 pounds, a position and locating system for 
diver use, and a diver’s underwater homing system. 
2. Future Needs 
There is an urgent need for tools designed 
especially for underwater work. In addition, we 
must consider the scientist’s tasks that will necessi- 
tate good tools. 
Future tool needs include: 
—All-purpose pneumatic wrenches. 
—Self-contained power tools or tools with power 
supplies small enough to be placed in the diving 
bell and that will function for hours on the 
bottom. 
—Tools adapted for scientific work, such as coring 
tools with self-contained power supply, bottom 
samplers with power supplies at or near the diver, 
and marine life sampling tools which do not 
disturb the bottom. 
In summary, the needs are for safer, more 
reliable tools for the commercial diver and special- 
ized tools for the scientific diver. 
3. Conclusions 
Recommendations: 
New, more sophisticated tools are needed for 
deeper diving commercial and scientific divers. (An 
artist’s concept of a futuristic diver working at 
great depths is shown in Figure 10.) To that end, a 
more concerted basic and applied research pro- 
gram must be implemented. Some industrial tool 
companies already are making preparations for 
such work, but Federal assistance would expedite 
progress. A Federally sponsored, long-range re- 
search and development program to provide im- 
proved tools and tool procedures would help, but 
a strong interim capability is needed now to 
support present programs in the commercial, 
military, and scientific community. 
