Skip to main content
No. 91:
Liberty Ships

Today, we watch an amateur build ships. The University of Houston's College of Engineering presents this series about the machines that make our civilization run, and the people whose ingenuity created them.

Author James Chiles notes that the United States built only two freighters between 1922 and 1937. Our merchant shipbuilding was nearly dead on the eve of WW-II, and the Axis nations were torpedoing allied ships off the surface of the ocean. England in particular needed ships, and they needed them right away.

To make matters worse, allied shipbuilders were hopelessly preoccupied with warships. Somebody would have to start making freighters from scratch. In 1940 the English were desperate enough to turn to an American group of heavy-construction companies led by Henry Kaiser, who'd never built any sort of ship.

The English carried with them the plans for a kind of generic freighter -- functional, not fancy. Kaiser had neither workers nor shipyards with which to make these ships. But he turned his lack of preparation to remarkable advantage.

Did it take years to train a well-rounded shipbuilder? Fine. He rearranged work so he didn't need well-rounded people. He broke shipbuilding into components and prefabrication so that each worker had to learn only a small piece of the job. Did he need heavy equipment to cut metal plate? No matter. He simply used oxyacetylene torches. In one case, he cut the time it took to train novices to tightrope across steel structures by hiring ballet dancers as fitters.

Kaiser redefined shipbuilding to match his resources. For the first time, he did it with assembly-line techniques -- interchangeable parts on a gigantic scale. His product, the Liberty Ship, was 440 feet long, and it carried 9,000 tons of cargo. The first one came off the ways just after Pearl Harbor. During 1942 ships were launched within less than a month -- then in just ten days -- and finally one was launched after just four days' time. Kaiser ate steel so rapidly that he had to set up his own mill.

Behind all the schoolboy excitement lay a darker side. We produced 11 million tons of shipping in 1942, but submarines sank 12 million tons. In 1943 we raised that to 20 million tons of shipping, and we prevailed. The Liberty ship saved us.

Kaiser's genius lay in his freedom of mind. By holding shipbuilding up to the clear light of amateur scrutiny, he brought it into the twentieth century. But what he did was rooted in a powerful common purpose, and that purpose ended with the war. First Japan, and now Korea, have claimed Kaiser's legacy and built on his methods. And now they dominate world shipbuilding.

I'm John Lienhard, at the University of Houston, where we're interested in the way inventive minds work.

(Theme music)

Chiles, J. R., The Ships That Broke Hitler's Blockade. American Heritage of Invention & Technology, Vol. 3, No. 3, Winter 1988 pp. 26-32, 41.

This episode has been greatly revised as Episode 1525.