Appendix C 



CONCEPTUAL DESIGNS FOR 

 CANDIDATE NEAR BOTTOM TRANSPORT SYSTEMS 



HEAVY-LIFT SUBMERSIBLE 



Three configurations are investigated: (1 ) deballasting using 

 high-pressure helium, (2) deballasting using a hydrazine gas generator, and 

 (3) a vehicle employing buoyant ring-stiffened cylindrical lift tanks. 



High-Pressure Helium System 



1. Ballast Tanks. Two cylindrical tanks with hemispherical end 

 caps would be used. Each tank will provide a nominal buoyant lift of 

 10 tons (the weight of helium in the tanks after deballasting will be 

 neglected). 



, . .. u» [ (2)(4)(7r)(r^) , rr{d')(h) ] 

 displ = (vol of tank) y = + ;; 64.0 



diSpl = IMilll + IGTTd^h 



Rearranging 



displ 

 h = TT-^ - 1.33d 



Let d =4.0 ft 



then h = 19.6 ft 



and total length of each tank = 19.6 -h 4.0 = 23.6 ft 



139 



