Abstract: A submarine has a pressure hull 20 which includes a number of adjoining transparent viewing sections 21 and 22 in the shape of truncated spheres. The sections 21 and 22 are clamped to a body section 23, 24 by a cage 40 and tension rods 44 which pass slidably through a thrust ring 38 interposed between the transparent sections. Access to a passenger compartment within the pressure hull is obtained via a hatch 32 in a mid section 23. The pressure hull is housed in an external hull designed for surface cruising. Ballast tanks are formed between pressure hull and the external hull, and the tie rods pass through low pressure seals to pivotal anchorage points within the ballast tanks.

Abstract: A submarine has a pressure hull (20) which includes a number of adjoining transparent viewing sections (21 and 22) in the shape of truncated spheres. The sections (21 and 22) are clamped to a body section (23, 24) by a cage (40) and tension rods (44) which pass slidably through a thrust ring (38) interposed between the transparent sections. Access to a passenger compartment within the pressure hull is obtained via a hatch (32) in a mid section (23). The pressure hull is housed in an external hull designed for surface cruising. Ballast tanks are formed between pressure hull and the external hull, and the tie rods pass through low pressure seals to pivotal anchorage points within the ballast tanks.