Aircraft carriers are, how to say, big. Building them is a lot easier if you have a really, really big crane. Meet Big Blue. She's the largest crane in the western hemisphere, and she's hard at work piecing together the new Ford-class aircraft carriers in Newport News, Virginia.
Big Blue is a gantry style crane that stands 233 feet tall, and has a span of 540 feet from leg to leg. It weighs 4,600 metric tons (10.1 million pounds). It was built in 1976 by the German company Krupp. The two legs straddle the huge dry-dock at Newport News Shipbuilding, where the first Ford-class aircraft carrier is currently being assembled. On each side of the dock are a pair of rails, so the entire craned can move up and down the ship's length, and the payload is attached to a carriage on the main girder that can translate side to side.
As originally installed, it could lift 900 metric tons (just under two million pounds), but in preparation for building the Ford-class carriers the shipbuilders needed to increase that. Krupp quoted them a pretty large figure. Newport News Shipbuilding said, "Naaah, we'll just do it ourselves." Now, each of the three hooks can carry 350 metric tons, bringing the crane's lifting capacity to 1,050 metric tons (that's just over 2.3 million pounds). Each hook has over a mile of 1-5/8-inch diameter wire rope behind it.
Why would you need such power-heaving capability? Super-lifts. It is a lot easy to build on firm, flat land than it is within the confines of a dry-dock, on the hull of a half-built aircraft carrier. So the carrier is built in large blocks, called super-lifts, which may weigh up to 1,047 metric tons. Once the super-lift is completed, Big Blue picks it up and carefully maneuvers it into place, where it gets permanently installed on the ship.
We had the opportunity to explore Big Blue when we were there in July. The elevator that takes you to the top is about the size of a phone booth. It rattles as it slowly takes you and two others up, and the journey seems to last forever. Once on the top deck you can see the whole town and you get an amazing bird's-eye view of the Gerald R. Ford aircraft carrier being built below you. The control room is a small capsule that hangs down beneath the girder, and you have to take a series of long, steep ladders to get into it. Once there, it's like you're dangling in a glass bird's nest full of touch-screens.
Big Blue has assisted in building every aircraft carrier since the USS Theodore Roosevelt, which began construction in 1981. She's nowhere near as powerful as China's Taisun, which can lift 20,000 metric tons (that's 98 Statues of Liberty). But she's still a pretty damn impressive crane.
