COLLAPSE 



DEPTH IN 

 FEET 



10,000 



20,000 



30,000 



40,000 



50,000 



60,000 



70,000 



0.2 0.3 0.4 0.5 



WEIGHT OF SPHERE 



WEIGHT OF DISPLACEMENT 



IN SEAWATER 

 a) [After Bernstein, Ref. (4)] 



STEEL 



ALUMINUM 



TITANIUM 



GLASS 



0.6 



QUALITATIVE COMPARISON OF FACTORS INFLUENCING 

 SELECTION OF MATERIALS FOR HYDROSPACE VEHICLES 



S- STEEL 



AL - ALUMINUM 



TI-TITANIUM 



GP-GLASS-REINFORCED PLASTIC 



CG-CAST GLASS 



O 



STH£NGTH*OENSITV 



OESICNABILITV 



FABRICABIIITY 



S AL Tl GP CG 



PROOUCieiLITV 



b) [After Gross, Ref. (12)] 



Fig. 5.3 a) W/D ratio vs. collapse depth of five material candidates for spherical pressure hulls, 

 b) Qualitative comparison of pressure hull materials. 



248 



