by windows, television, or periscopes. Telechiric devices should operate 

 with the maximum number of degrees of freedom possible so that the 

 human masters can attach, position, and detach loads with dexterity. 

 Three basic approaches for achieving a workable Near Bottom 

 Transport System are discussed in following portions of the report. One 

 concept, an underwater helicopter (perhaps hydrocopter is more appropriate) 

 would rely on mechanical means to generate the required lift. A heavy-lift 

 submersible is considered to be another reasonable candidate system. Several 

 alternate means for achieving variable ballast with such a submersible are 

 described. A third choice is a bottom-crawling NBTS. 



HEAVY-LIFT SUBMERSIBLE 



A submarine capable of a 10- to 30-ton lift at 6,000 feet presents 

 some unusual design problems, not the least of which is the development of 

 a practical, variable debal lasting system. Several possible approaches for 

 supplying the ballast have been suggested and include: 



1. Lift provided by syntactic foam, glass spheres, or gasoline filled 

 containers. 



2. Lift provided by high-strength steel pressure chambers maintained 

 at a one atmosphere internal pressure. 



3. Displacement of water ballast by gas produced from hydrazine 

 or other gas generators. 



4. Displacement of water ballast by a low-density gas such as 

 helium stored in reservoirs at high pressure. 



Concepts 1 and 2 are similar in design approach. Each vehicle is 

 envisioned as having component parts consisting of: (1 ) a buoyant personnel 

 sphere mounted on a structural steel framework (the sphere can be released 

 from the vehicle in the event of an emergency); (2) battery packs to power 

 the vehicle propulsion systems, interior and exterior lighting, telechiric 

 devices, and winches; (3) lift buoys; (4) large, expendable ballast weights, 

 and (5) a load attachment system. The two concepts differ in the choice of 

 buoyant lift elements. One relies on the permanent buoyancy offered by 

 syntactic foam or encased gasoline or other petroleum derivatives. This 

 vehicle would descend to the sea floor carrying an expendable ballast weight, 



74 



