BATH, Maine (AP) - The largest destroyer ever built for the U.S. Navy is futuristic and angular. But its hull is based on a design that dates to pre-dreadnought battleships a century ago.

BATH, Maine (AP) The largest destroyer ever built for the U.S. Navy is futuristic and angular. But its hull is based on a design that dates to pre-dreadnought battleships a century ago.

The Navy chose a modern take on an old-school design called the "tumblehome" hull for the future USS Zumwalt because it contributes to the ship's stealth.

The ship has something of a pyramid shape because of the hull's shape, and critics say the ship could become unstable in some conditions. But the Navy says there's been extensive testing to ensure it's safe.

The behemoth, which is 600 feet long and weighs 15,000 tons, will be put to the test when it goes to sea in December. Shipbuilder Bath Iron Works will test its performance and make tweaks this winter. The goal is to deliver it to the Navy sometime next year.