June 20, 2012: The U.S. Navy has ordered the second (the USS Tripoli, LHA 7) of two amphibious ships that will not have a well deck for landing craft. The first of these well-less LHAs, the USS America, will enter service next year, with the Tripoli to follow in 2018. After that the navy will wait to see how the first two of these ships perform before building any more.
The navy had tried this concept before, as the LPH (Landing Platform Helicopter) in the 1960s. Seven 18,000 ton ships were built from scratch as LPHs, while four others were older carriers that were simply modified a bit for this sort of thing. Noting the proliferation of anti-aircraft weapons, and the vulnerability of helicopters in a combat zone, the navy backed away from LPHs and by the 1990s they were all gone. But now the idea has returned, at least in the form of two ships.
The America class LAHs are big ships (45,000 tons, 257 meters/844 feet long) and, like all other American amphibious assault ships, look like small aircraft carriers. But the Americas are larger than earlier LHAs and have no well deck taking up lots of space in the stern. The Americas have a crew of 1,050 and carry 1,600 marines as well as 32 aircraft (helicopters, V-22s, and F-35Bs). The reasoning behind this design is that the proliferation of anti-ship missiles makes it too risky to get close enough for landing craft. So now it's back to LPHs and longer range transports like the V-22.