Unclassified 



DOCUMENT CONTROL DATA - R 8. D 



Naval Civil Engineering Laboratory 

 Port Hueneme, California 93041 



Unclassified 



DEVELOPMENT OF A SPHERICAL ACRYLIC PLASTIC PRESSURE HULL FOR 

 HYDROSPACE APPLICATION 



3CRIPTIVE NOTES (Type of report and inclusive date a) 



Final; October 1964-October 1969 



THOHUI (F/rtl name, middle Initial, laat name) 



J. D. Stachiw 



April 1970 



217 



22 



YF 38.535.005.006 



TR-676 



NO(S> (Any other numbers that may be aaslgned 



This document has been approved for public release and sale; its distribution is unlimited. 



Naval Facilities Engineering Command 

 Washington, D. C. 



A spherical, acrylic plastic capsule has been designed for protection of man against the 

 external hydrostatic pressure present at continental shelf depths. Experimental and analytical 

 studies have been conducted to evaluate the performance of both the spherical capsule design 

 and the acrylic plastic construction material at continental shelf depths. Results from testing 

 twenty-two 15-inch-outside diameter models and a large-scale prototype under short-term, cyclic, 

 and long-term hydrostatic pressure indicate that the design and material chosen meet the require- 

 ments for safe operation at continental shelf depths. A prototype 66-inch-OD capsule of 2.5-inch 

 wall thickness, and 4,000-pound positive buoyancy in seawater has been specifically developed 

 for the NEMO (Naval Experimental Manned Observatory) system. The NEMO prototype capsule 

 successfully withstood 105 simulated dives ranging from 250 to 2,400 feet prior to being tested 

 to implosion at a simulated depth of 4,150 feet. Until more experimental data are generated on 

 the fatigue life of the full scale NEMO capsule under different pressure loadings, the capsule is 

 considered to be safe for manned operation only to the 600-foot depth. 



DD 



.,1473 



Unclassified 



S/U 010 1-807-6801 



