Detroit’s Production Battle to Win World War II

In honor of the men and women who gave their lives for our freedom, we present this past article, which tells the story of how the American auto industry came together to supply our forces with the weapons needed to win World War II. Please enjoy, and have a happy Memorial Day.

In 1940, the United States was depleted and alone. Decades of isolation and a global depression had created a nation unresponsive to the world beyond its borders. But the battles raging in Europe and Asia were growing steadily closer.

Despite serious opposition to joining another foreign war, President Franklin Roosevelt understood the magnitude of the pending carnage. We weren’t ready when he mentioned the Arsenal of Democracy 75 years ago, but he planted the seeds to the most prolific—and most lethal—manufacturing story in the history of the world. It has never been repeated, and it likely never will be.

“The more you study it, the more you learn about it, the harder it is to believe it actually happened,” said A.J. Baime, an automotive journalist and the author of The Arsenal of Democracy: FDR, Detroit, and the Epic Quest to Arm America, a New York Times best-seller.

The Cadillac of Tanks: A worker directs a crane operator to lower an M-24 tank. The Cadillac plant converted from civilian cars to tanks in 55 days.

Seventy-five years ago, even the kingpins of Detroit—General Motors’ Bill Knudsen, Chrysler’s K.T. Keller, and Dearborn’s Edsel Ford—couldn’t fathom what their companies would accomplish in preparing us for war. They were car men pushing metal down assembly lines. (Knudsen left GM to lead Roosevelt’s war effort, becoming the architect of America’s arsenal. He worked for $1 a year.)

In 1939, the U.S. military was laughable. The Army’s own chief of staff, Gen. George C. Marshall, ranked it 19th in the world, one spot behind Portugal, in a report to the president. Roosevelt was about to change that—and America—forever.

“We must be the great arsenal of democracy,” Roosevelt said during his December 29, 1940 fireside chat. “For us this is an emergency as serious as war itself. We must apply ourselves to our task with the same resolution, the same sense of urgency, the same spirit of patriotism and sacrifice as we would show were we at war.”

The Axis powers laughed at the speech and scoffed at subsequent production goals. In 1942, a month after the attack on Pearl Harbor, Roosevelt said America would build 60,000 planes for the year, and the next year it would more than double that number.

Carmakers shifted production to war materials by February 1941, though some work started a year earlier.

Suppliers around the nation, shorthanded and scrounging for raw materials, worked nonstop: destroyers out of Boston, battleships out of Philadelphia, P-51 Mustangs out of Inglewood, California. If there was a factory anywhere in the U.S., it made something for the war.

Suppliers around the nation worked nonstop; Detroit was the beating heart.

Detroit was the beating heart. Carmakers built everything: tanks, airplanes, radar units, field kitchens, amphibious vehicles, jeeps, bombsights, and bullets. Billions and billions of bullets. Detroit, with 2 percent of the population, made 10 percent of the tools for war.

Ford promised—and delivered—one B-24 Liberator every hour by the end of the war.

The U.S. produced more than planes and tanks during World War II.

“Perhaps the most amazing thing was the speed in which they changed over from cars to war machines,” said Bob Kreipke, Ford’s corporate historian.

Indeed, many projects began before the war started. But after December 7, 1941, all private automotive production stopped within three months. Car tools were pushed to the side and covered with tarps as tool-and-die men created the implements of war. Assembly lines were reconfigured. Tens of thousands of people were hired and trained. Logistics of unimaginable proportions were penned to get Spitfire engines to England, tanks to Russia, and guns to China, all the while building up America’s very real military arsenal. Blueprints were studied, shared, and often improved.

“One important fact to consider,” said Brandt Rosenbusch, U.S. manager of the historical archives at Fiat Chrysler Automobiles, “is how Detroit became progressively more efficient at building things during the war.”

The 40mm Bofors guns made by Chrysler

Chrysler had been tasked with building 40mm anti-aircraft guns, known as Bofors guns, which initially took 450 man-hours to build. By the end of the war, Chrysler cut that time to 10 man-hours.

Similar stories echoed along Detroit’s Woodward Avenue. Aircraft builders in California first sneered at Ford’s promise to deliver one B-24 Liberator every hour by the end of the war from a facility not yet built and 35,000 workers not yet hired. But Ford delivered. When Keller was asked by the War Department if Chrysler could build a tank, he gave a resounding “yes” before asking, “What’s a tank look like?”

Nothing was impossible, whatever the assignment. Products rolled off assembly lines faster than spinach grew in a victory garden.

“There was amazing ingenuity and will to get things done,” said Greg Wallace, GM’s Heritage Center director.

Ford built the largest aircraft factory in the world in just over a year. Willow Run featured 3.5 million square feet of factory space and an assembly line more than a mile long. Chrysler broke ground on its tank assembly plant in October 1940 in Warren, Michigan. The first tank rolled off the assembly line in April 1941—before the plant was finished.

Even when production started, things never ran smoothly. “They were changing the design of these products on the fly,” Charles Hyde, retired Wayne State University professor and author of Arsenal of Democracy: The American Automobile Industry in World War II, said. “Every couple of weeks, they would modify the design, making hundreds, sometimes thousands of changes. There was little testing except by the soldiers in the field.”

The introduction of women in factories was revolutionary. They were essential in aircraft and munitions assembly, but women rarely made the same wages as men.  

Everything from initial product quality and the lack of women’s restrooms at factories to the loss of trained employees to the military and the need for raw materials was a constant drain, Baime said. “It was all about problem solving, but the problems never ended.”

Eventually, every problem found an answer. Carmakers tasked with making bullets learned that copper shortages would not allow them to use brass. In less than six months, metallurgical scientists from Detroit discovered a way to make the cartridges out of steel, and production was underway.

When engineers needed a tank engine fast, they created the Chrysler A57 Multibank, which tied five engines together to create a 21-liter 30-cylinder engine that produced 425 hp and 1,060 lb-ft of torque. It wasn’t the most elegant solution, but it worked, it was cheap, and it fit inside a Sherman tank.

So much was possible, in part, because of the immense cooperation. “Before the war, these companies were intense rivals,” Baime said. And none of them cared for the pro-union, capitalist-bashing Roosevelt.

Willow Run had a sharp turn to avoid Washtenaw County, which Ford said was full of liberals.

During the war, however, companies worked together extensively, sharing plans and proving grounds, Hyde said. When the military selected the Willys-Overland MB as its primary small vehicle, Willys didn’t have the capacity to meet the order, so Ford was asked to build it, too. That vehicle, commonly known as the jeep, returned to America, and a newer version was created for civilians. It was one of the few vehicles to have a life after 1945.

Perhaps the biggest lesson carmakers learned during the war was how to quickly change lines and retool on the fly, Kreipke said. No one in the world did it as well as America. That meant consumers would see a large number of new car styles and frequent changes. Choice and abundance became a staple in America’s post-war car culture.

But the Arsenal’s impact on the U.S. was deeper. It introduced more women to the workforce and began to put cracks in the walls of segregation. It changed the way people saw themselves and others. The work was hard, the hours were long, and by no means should nostalgia cause anyone to forget the brutality of what that work begat. Americans united like never before in the absolute obliteration of our enemy.

That changed our future—a future created on an assembly line that started in Detroit.

The production numbers during World War II show how America outproduced the world.

Source: The National World War II Museum, New Orleans

Come Bearing Bearings

A Chevrolet worker uses an air tool during assembly at a plant in Toledo during the war.

The wheels of war would cease moving without ball bearings. So would the machines that build the wheels of war, which cannot operate without the proper bearings to reduce friction between moving metal parts.

In fact, the U.S. military attempted to destroy factories in Schweinfurt and Regensburg, Germany, specifically because they produced bearings. Destroy the bearings, destroy production, and end the war six months early, strategists thought. But the first two raids proved utter disasters for the Americans for a multitude of reasons, including strong defenses surrounding the factories that made the innocuous cogs that enabled Germany’s deadliest machines.

The Germans intended to protect their bearings as long as possible.

Hard Right: Building Willow Run

Ford used two nine-hour shifts to build the B-24 as the pilot and crew slept on cots waiting for delivery.

Designed by famed Detroit architect Albert Kahn, Willow Run was a monument to the mechanized world. The building featured 3.5 million square feet of assembly space, employed 35,000 to 42,000 people, built 8,600 B-24 Liberators during World War II, and had a mile-long assembly line with 28 stations. A special forge at the plant could crank out 5 million rivets a day.

One special feature was the 90-degree turn the assembly line took. Ford built a rotating table to turn an airplane during assembly and continue it down the line. The reason for the hard right, according to Ford’s historian, was to keep the assembly plant out of Washtenaw County, where Ford said he did not want to give Democrats one cent of his tax dollars.

E=MC Detroit

GETTY IMAGES

Scientists in Los Alamos, New Mexico, working on the most secret project in World War II enlisted Detroit to build their atom bomb. Those scientists believed only pure nickel parts could resist the corrosive powers of the hexafluoride gas used inside Fat Man and Little Boy, but producing two pure nickel containment spheres would require all the nickel mined in the U.S. for the next two years. Chrysler was able to show that specially nickel-plated parts could work just as well, and it set up a shop near Detroit to build them. However, workers could not know what they were building, what it was for, or when it needed be done. Another Chrysler factory nearby built engines that would power the B-29 Superfortress, the plane that would deliver those devices.