Sept. 2, 2025, marks 80 years since the end of World War II, offering an opportunity to reflect on how U-M’s contributions to wartime research, training and service impacted that period.
After the United States entered World War II in late 1941, some called for universities to be turned over entirely to the armed forces. But U-M President Alexander Ruthven refused. He reasoned that the war would end eventually, and the people of Michigan would still need their university. So, classes continued.
Ruthven did, however, open the campus to collaboration with the War Department. Education and research would be the university’s wartime contribution.
That choice reshaped the institution from 1941-45. Soldiers and sailors filled dormitories and classrooms, while faculty scientists conducted secret experiments behind closed doors. The most consequential of those projects was the development of something called the “Variable Time Proximity Fuse.”
This fuse technology was developed after the London Blitz of 1940-41, when British anti-aircraft gunners struggled to bring down German bombers. Shells had to be fired with great precision, and even timed detonations missed as planes zig-zagged through the sky.
Then Allied scientists had an idea: create a shell that would send a radio signal toward a German bomber, then, when the signal bounced back to the shell, it would cause the explosive to detonate, destroying the plane without having to hit it.
U-M physicists David Dennison and H. Richard Crane, experts in radio technology, were tapped, along with other scientists and engineers in the U.S. and Britain, to help bring this idea to life. Under the authority of the National Defense Research Council, the two men and their teams conducted 50,000 tests on copper model planes strung on pulleys near campus. The challenge was significant. Glass tubes and circuits had to survive the launch, and the fuse needed a timer to prevent premature explosions that might kill the artillery crew.
By mid-1942, the team had succeeded. On Aug. 13 of that year, the U.S.S. Cleveland tested the new fuses against three radio-controlled drones over Chesapeake Bay. The planes weaved in the air, but four shells brought them down. After that, production of the new fuses began. Ultimately, the fuses proved decisive, breaking up attacks during the Battle of the Bulge.
more on u-M during WWII:
The proximity fuse was only one of nearly 200 secret wartime projects at U-M. Researchers also accelerated the production of explosives, advanced radar technology, and helped develop a synthetic fabric for uniforms that kept wearers dry. Meanwhile, the campus itself became a training hub.
The Law School hosted nearly 2,500 JAG lawyers; East Quad was converted into an Army program for Japanese-language translators; and West Quad became “The Ship,” home to 1,300 Navy apprentice seamen pursuing accelerated degrees. In total, U-M trained 4,000 men for the Navy and Marine Corps, 9,500 for the Army (including 1,500 Japanese speakers), and 12,000 civilian contractors.
But it was the proximity fuse that stood as Michigan’s signature achievement. Ten days after Japan’s surrender, Army Gen. Brehon Somervell wrote to Ruthven: “Your institution has played a very important part in producing the material which has been such a decisive factor in winning the war.”
