This thing is HUGE!
http://www.bwxt.com/Products/mob-bwx.html "JMOB at a Glance
The Joint Mobile Offshore Base (JMOB) will enhance the ability of the United States to provide logistical support for the projection of power and aid worldwide. At the same time, it will lend greater security to the men and women on it.
And compared with traditional land bases, this moveable, reusable investment is
not subject to the politics of other nations , enabling military equipment to be prepositioned in the theater of interest within 30 days nearly anywhere in the world."
Self-powered, semisubmersible supply and theater vessel.
Five individual single-base units, each 1,000 feet long, connected together to form a one-mile floating runway 500 feet wide and 20 feet above the ocean surface.
Deployed as five single-base units at 15 knots; 30 days from U.S.
to operation anywhere in the world.
Survivable in all sea states (50-foot seas with 100-knot winds).
Total of 5 million square feet, with 3.5 million square feet (80 acres) of climate-controlled storage space to preposition 300,000 tons of equipment and supplies with 75 million gallons of fuel and
50 million gallons of potable water.
All materiel directly available for on-board operation prior to theater use.
JMOB has an amphibious-launch-compatible "artificial" beach.
Below-deck roadways between units.