24 THE NAVY OCEAN ENGINEERING PROGRAM 



Once the sea floor has been entered, and a working atmosphere estab- 

 Hshed, the use of available boring machines can be used to extend such a 

 base. These boring machines are capable of forming tunnels of from 15 to 

 20 ft in diameter in most types of rock. 



BOTTOM STATIONS 



Concepts for a manned underwater station which would allow the Navy 

 to establish fixed habitats on the sea floor on the continental slope at 

 depths down to 6000 ft have been developed. The initial criteria defined 

 a station capable of supporting five-man crews at a pressure of one atmos- 

 phere in a shirt-sleeve environment for an indefinite period of time. 

 The station would have a self-contained power source and a self- 

 contained life-support system which would make it independent of the sur- 

 face. Resupply of the station would be on the sea floor. Upon completion 

 of its missions, the station would be capable of being recovered and moved to 

 other locations. Studies to develop the one-atmosphere manned under- 

 water station have revealed several feasible approaches. 



Each approach can be considered as a system composed of subsystems 

 such as structure, power, life support, placement and recovery, and com- 

 munication controls and instrumentation. 



Structural shapes feasible with today's technology which have been con- 

 sidered are the sphere, the cylinder, and the toroid. Each design assumed 

 the use of a high-strength material such as HY 140 steel. 



Foundation requirements for each structural shape are different in 

 design, concept, and materials. The toroid will rest on the bottom on a 

 cone-shaped foundation which adjusts to a bottom slope. The cylindrical 

 station is supported by three legs which adjust to bottom irregularities. 

 Emplacement modes for all three shapes could be either free-descent tech- 

 nique, utilizing negative buoyancy, or the winch down. This latter method 

 would keep the station positively buoyant at all times and would require 

 winching against a sea floor anchor. 



Life support and power requirements are a function of station mission 

 and duration. Power systems considered for use include nuclear reactors, 

 radioisotopes, silver zinc batteries, and surface conventional power with 

 a surface buoy and umbilical. Using today's technology Hfe support sys- 

 tems for a 30 day, five-man mission require approximately 500 gallons of 

 potable water, 330 cubic feet of compressed oxygen, 560 pounds of 

 lithium hydroxide for CO2 removal, and 200 pounds of dehydrated pre- 

 cooked food. 



