40 



DESIGN OF THE SEALAB II HABITAT 



Fig. Z3. The berthing area of the Sealab II habitat 



Viewing Ports 



The hull is provided with eleven viewing ports. These ports are approximately two feet in 

 diameter and capable of withstanding the internal design pressure of 125 psig. 



Access Openings 



The hull is provided with three access openings. The bottom entry hatch is approximately 

 four feet in diameter and located in the hull bottom in the entryway. The emergency escape 

 hatch is approximately 27 in. in diameter and located in the hull bottom near the bow. The 

 surface access hatch is approximately 27 in. in diameter and located in the top of the hull 

 amidship. 



Entry Trunk 



The entry trunk is eight feet by eight feet and extends two and one-half feet below the hull 

 bottom. This trunk provides a displacement volume to compensate for the expected bottom- 

 pressure variations due to tidal action in addition to normal internal pressure changes. 



Shark Cage 



The shark cage is eight feet wide by 12 ft long, and extends from the entry trunk down to a 

 point one foot above the Sealab II support base. A one-foot-high flexible extension is attached 

 around the bottom of the shark cage. This allows conformity with an uneven sea bottom. 



