Conclusions. The concept of buoyant assist initially appeared to 

 offer great promise. However, it was found that an important disadvantage 

 of the system is the possibility of extreme dynamic overloads in even 

 comparatively mild seas. Secondly, there is always some uncertainty in 

 remotely activated devices, such as the valves which must open to flood the 

 units. In general, all buoyancy-aided systems must be considered develop- 

 mental items of uncertain potential, particularly since they are considerably 

 more complex when compared to the other candidate heavy-lift systems. 



OPERATIONAL ANALYSIS 



After the necessary background data were gathered or derived, the 

 next step was to perform an effectiveness evaluation of the proposed 

 solutions. From this analysis it is possible to specify clear-cut points of 

 departure for refined analyses of the more desirable systems. The following 

 paragraphs provide some discussion of the steps used to evaluate the 

 candidate systems. 



Environmental Factors 



The natural environmental conditions under which a system is 

 required to operate can vary within fairly wide boundaries. The following 

 factors enter into the environmental analysis of each system: 



1 . Sea state 



2. Currents 



3. Wind 



4. Air temperature 



5. Water temperature 



6. Water density 



7. Hydrostatic pressure 



8. Turbidity 



9. Soil properties on the bottom 

 10. Biological/chemical environment 



These factors are evaluated as necessary in the analysis of each system and 

 enter into the discussion only when they may possibly reveal important 

 differences between alternate lift systems; moreover, they are analyzed only 

 in the depth necessary to adequately expose these differences. 



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