critical problem. New advances in various state-of-the-art techniques 

 also could eliminate what are now considered barriers, and of course 

 new problems could arise. 



The experience of NUC CURV program development indicates that 

 the technical barriers to the development of a deep operating immanned 

 system are not insurmotintable. The cable problems are basically a 

 matter of trading off desired system capabilities and cable size to reach 

 the optimum configuration. Bottom navigation is a question of making the 

 search time and navigational accuracies involved reasonable. Therefore 

 the matter of eventually developing a 20,000-foot unmanned system is not 

 seriously in question at this time. 



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