New mini-carrier

USS America. [Link]

She’s 844 feet long, 106 feet wide and displaces 45,000 tons of water. The future USS America,christened in Mississippi on Saturday, is technically an amphibious assault ship, a type of vessel optimized for carrying Marines into battle. But subtle changes under America‘s steel skin mean she can double as a small aircraft carrier, capable of sustaining a short air war all on her own.

The changes to America and her sister ship Tripoli came at the cost of some of the usual amphibious capabilities possessed by assault ships. By investing a combined $6 billion in America and Tripoli, the Navy and Marines are betting that future warfare will involve more aerial combat and fewer potential beach assaults.

It’s not a totally reckless wager, but it does involve some risk. With the America class, the Pentagon istaking a chance on air power and, more to point, on the Marines’ version of the F-35 Joint Strike Fighter. When America‘s sister ship Tripoli enters service in 2018, the Navy will (in essence) possess 13 carriers — these two smaller, newer models, plus 11 of the big, nuclear-powered variety. That’s up from the 11 nuke flattops in today’s fleet. Commensurately, the number of old-school assault ships will drop by two.

The sailing branch’s other assault ships — currently numbering nine — can also support dozens of helicopters plus a handful of Harrier jump jets apiece. But they lack the facilities for sustained flight ops, meaning they’re more assault ships than classic carriers. The older vessels are built around cavernous “well decks” — in essence, giant swimming pools that open to the sea through the ships’ sterns, allowing them to launch and recover landing craft, hovercraft, swimming vehicles and river boats. These small craft are the primary means of moving Marines onto shore, complemented by helicopters and V-22 tiltrotors taking off from the flight deck.

America and Tripoli don’t have well decks. In their place, the newer ships possess extra hangar space, bigger tanks for aviation fuel and larger weapons magazines. These facilities allow America and her sister to operate, for days on end, as many as 30 fixed-wing planes including today’s Harriers plus the F-35B stealth jump jet that’s still in testing. “It is, for all intents and purposes, a light aircraft carrier,” Navy Capt. Jerry Hendrix wrote of America. But the new ship and her sister can still send Marines ashore in helicopters and V-22s.

That shift toward aerial capabilities was deliberate on the part of the Marine Corps, and reflects continuing doubt about the usefulness and wisdom of World War II-style beach assaults, which were among that conflict’s bloodiest operations. Two years ago, then-Defense Secretary Robert Gates considered eliminating the beach-invasion mission altogether, although he ultimately settled for merely de-emphasizing it.