Fig 9,29 Viewport arrangements on. a) ALVIN and b) DS-4000 (WHOI. US, Navy) 



signed vehicles of this class. Cousteau de- 

 cided early that the primary design goal was 

 photography and viewing, and he met this 

 goal admirably. Figure 9.29b shows DS- 

 4000^8 bow — the two large viewports are 16 

 degrees from the vertical centerline and look 

 downward 21 degrees from the horizontal. 



The field of view, in water, is 74 degrees from 

 each viewport with an overlap of some 42 

 degrees. This arrangement provides both the 

 pilot and the scientist virtually the same 

 view. The solution is an excellent one for this 

 depth vehicle. Particularly attractive is the 

 smaller viewport above and between the two 



454 



