What You Need to Know: The U.S. Navy's four conventionally-armed Ohio-class submarines (SSGNs), converted ... modified to lockout-out chambers for Dry Deck Shelter (DDS), NavalNews.com explained.

The SSGN Ohio-class is also capable of deploying a Dry Combat Submersible, a miniature submarine that special forces use for stealthy underwater transportation. Each Ohio SSGN costs $3.53 billion ...