NEAR BOTTOM TRANSPORT SYSTEM 



A need probably exists for a load handling system which would 

 operate at or near the sea floor. Its principle mission would be to lift loads 

 weighing 10 to 30 tons from the ocean floor, transport them to preselected 

 construction sites, and accurately place them at the site. This system is 

 conceived as a vehicle — self-sufficient, if possible, in both life support and 

 power subsystems — which would evolve into the "tractor, fork lift, and 

 crane" of future underwater construction programs. The kinds of loads to 

 be carried by the transport subsystem would include: (1 ) trenchers, dredges, 

 or drilling systems which lack the mobility to roam at will on the ocean floor; 

 (2) transportable nuclear power sources which would provide power for 

 habitats as well as for construction subsystems; (3) underwater winches and 

 anchor blocks which would serve as components in sea floor construction 

 systems; and, perhaps most importantly, (4) construction elements such as 

 foundations, prefabricated concrete panels, and metal plates and girders to 

 be used in building manned bottom installations. Construction materials 

 could be stacked on pallets aboard surface vessels for easy off-loading by the 

 Near Bottom Transport Subsystem (NBTS). The palletized load, weighing 

 several hundred tons, would be lowered to the ocean bottom by the lifting/ 

 lowering subsystem and an acoustic beacon atop the load would guide the 

 NBTS to the proper bottom site for rendezvous. 



PERFORMANCE CRITERIA 



A practical NBTS should meet certain cost and performance criteria. 

 Some of these criteria previously specified as outlined in the DOT TDP^^ 

 are listed below: 



Depth 6,000 feet 



Load capacity 10—30 tons 



Height of lift 20-100 feet 



Transport capability 300— 600 feet 



Alignment tolerance ±0.1— 0.5 feet 



(translation) 



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