The last ship to be launched down the ways was USS Mason (DDG 87) in 2001. Although these launches usually took about ninety seconds, a lot went into a smooth launch. The sliding ways had to have the right width to get the right amount of pressure on the grease that lubricated them. A destroyer may have launched on an inclined ways that was 4 feet wide, while the one for a large commercial ship could be 7 feet wide. Speed was also important, with a ship accelerating to between 15 and 18 miles per hour in a matter of seconds. Once it hit the water, it had to slow enough so it didn’t pull tug boats under, hit the bridge or get stuck in mud across the river.
