Appendix A 



DETAILED DIMENSIONS OF 66-INCH-DIAMETER 

 ACRYLIC PLASTIC HULL FOR NEMO SYSTEM 



Although the description of the 66-inch acrylic plastic hull in the 

 main body of the report is adequate for discussion of the acrylic plastic hull 

 design and its performance under hydrostatic pressure, it is not detailed 

 enough for the personnel involved in certifying the seaworthiness of the 

 acrylic plastic hull. The Certification Board requires not only a detailed 

 description of the plans from which the hull was built, but also how well 

 the finished product conformed to these plans. Only after the relationship 

 between the dimensions shown on plans and the dimensions of the finished 

 product is well understood can the dimensional deviations of future opera- 

 tional hulls be considered as acceptable or unacceptable. This statement is 

 based on the fact that the prototype 66-inch hull that successfully withstood 

 the many hydrostatic overloads to which it was subjected during the testing 

 program wasnot perfect, but deviated from the specified nominal dimensions 

 in a certain manner. If future hulls built for incorporation into manned sub- 

 mersibles show only as much (or less) dimensional and structural deviation 

 from fabrication plans and specifications as exhibited by the prototype, they 

 will be acceptable. Their performance should then be equivalent or superior 

 to the one shown by the prototype 66-inch acrylic plastic hull discussed in 

 this report. 



For this reason the figures and tables comprising Appendix A are 

 grouped to show in detail not only the drawings used in the fabrication, but 

 also the dimensional measurements performed on the hull structure during 

 and after the fabrication. Thus Figures A-1 to A-10 show the fabrication 

 plans, while Figures A-1 1 to A-1 3 show the quality control measurements 

 performed on the hull during fabrication. 



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