When I worked at McDonell Douglas (now Boeing) in St. Louis in the late 1960’s, the Viet Nam war was in full swing. The demand for F-4 Phantom Jet fighters was strong and we managed to move the assembly line fast enough to produce two jets a day. It was quite a feat. But it didn’t compare to the Michigan factory that produced one B-24 bomber an hour during World War II. This was one of the most astonishing tales of ingenuity in manufacturing history, writes The Wall Street Journal (May 14, 2025).
As 1939 began, the U.S. had fewer than 2,000 military aircraft. With war looming, President Franklin D. Roosevelt knew the country desperately needed to remedy the situation. He turned to America’s top manufacturers for help. One of them was the Ford Motor. In 1940 workers began constructing an enormous manufacturing-and-assembly plant and an airfield called Willow Run near Detroit. It was finished within 6 months.
After the Pearl Harbor attack, the plant was ready to mass-produce B-24 Liberators: bombers that weighed 18 tons, were 67 feet long and had wingspans of 110 feet. Could massive warplanes be built with the same assembly-line method as family automobiles? It had never been tried before.
Ford’s production genius, Charlie Sorensen, was put in charge. Soon 42,000 workers filled the factory floors in around-the-clock shifts. With so many Americans off fighting in Europe and the Pacific, some of the men and women at Willow Run had never done manufacturing jobs before. So a school was set up near the plant: Some 8,000 employees a week were taught to build airplanes.
Those four-engine B-24s each contained 1.2 million parts held together by more than 300,000 rivets. “Rosie the Riveter” entered the American lexicon, as women who had never before done such work helped manufacture the Liberators.
How long should it take to build an airplane? By the time Willow Run was operating at full capacity, a B-24 was rolling off the mile-long assembly line every 55 minutes. The nation needed those planes, and it got them. By war’s end, factories across the U.S. had built nearly 300,000 military aircraft.
Classroom discussion questions:
- Why does it take so much longer to build planes today?
- Which of the 10 Operations Management decisions (that your Heizer/Render/Munson text is built around–see Table 1.2) do you think were faced by Sorenson?