Willow Run, also called Air Force Plant 31, was a large factory in Michigan, United States. It was located between Ypsilanti Township and Belleville. The Ford Motor Company built Willow Run to produce aircraft, including the Consolidated B-24 Liberator, a type of large bomber. Construction of the Willow Run Bomber Plant started in 1940 and was finished in 1942.

Defense plant

Production at the plant started in the summer of 1942. The dedication plaque shows the date June 16. At first, the plant made parts for the planes. Companies like Douglas Aircraft and Consolidated Aircraft put the finished planes together. However, this method had problems, so by October 1941, Ford was allowed to build complete Liberators. The assembly line at Willow Run operated until May 1945, producing nearly half of all Liberators made.

There were 42,500 employees working at the plant. Each month, 8,200 workers were sent to military service. The Aircraft Apprentice School trained up to 8,000 students each week to prepare them for jobs. The building covered 3.5 million square feet. The building was more than 3,200 feet long and 1,279 feet wide at its widest point. Construction began on April 18, 1941. B-24 aircraft production started in late 1942. Parts and subassemblies were made at nearly 1,000 Ford factories and other independent suppliers.

Airport

Willow Run Airport was built as part of a bomber manufacturing plant during World War II. After the war ended, the airfield was taken over by civilians and is now managed by the Wayne County Airport Authority. At different times, part of the airport was used as a research facility connected to the University of Michigan and as a secondary Air Force base. The airport continues to function as a place for cargo flights and general aviation. Since 1992, the airport has hosted the former Yankee Air Museum and the National Museum of Aviation and Technology at Historic Willow Run, which is now called the Michigan Flight Museum.

Camp Willow Run

Willow Run is named after a small stream that flowed through open fields and forests near the border of Wayne and Washtenaw counties until the late 1930s. By the mid-1920s, a local family known as Quirk Farms had purchased land in Van Buren Township, which later became an airport. In 1931, automobile inventor Henry Ford bought Quirk Farms. Ford believed in the benefits of country living and used the land as farmland for an educational program that brought young men from cities to Willow Run Camp to learn about farming, nature, and rural life.

At Willow Run Camp, the residents planted, cared for, and harvested crops, and collected maple syrup. They sold these items at a market on the property. Through this work, the boys learned self-discipline, the value of hard work, and the benefits of fresh country air.

Camp Willow Run was for young men aged 17 to 19, many of whom were sons of soldiers who had died or been injured during World War I, or who helped support their families. According to the Benson Ford Research Center, the camp provided:

Henry and Clara Bryant Ford built seven chapels named the Chapels of Martha and Mary as a lasting tribute to their mothers, Mary Ford and Martha Bryant. The first chapel was completed in 1929 at Greenfield Village, Michigan. Others were built in the 1930s and located in Dearborn, Michigan (near the Fords' Fair Lane estate); Sudbury, Massachusetts; two in Richmond Hill, Georgia (the Fords' winter home); Macon, Michigan; and Willow Run.

The Willow Run Chapel was originally built for Camp Willow Run. After the war, Ford sold the chapel to Kaiser-Frazer, who later sold it to General Motors as part of the purchase of the Willow Run bomber plant. GM used the building to store files for an unknown period before selling it to the Cherry Hill Baptist Church. When Cherry Hill Baptist Church needed more space and decided to build a new church, it sold the chapel to the Belleville Presbyterian Church for one dollar in July 1978.

Today, the Willow Run Chapel of Martha and Mary stands a few miles from its original location on land that was once part of Henry Ford's Quirk Farms. Of the seven chapels, this is the only one still used regularly for worship. It retains its original pews and furnishings; the Greenfield Village chapel is the only other chapel with original furnishings still in active use.

Factory construction

During World War II, Ford Motor Company, which was led by Henry Ford’s son Edsel, focused its production on helping the Allied forces. In early 1941, the U.S. government created the Liberator Production Pool Program to meet the need for B-24 bombers. Ford joined the program and not only built the bombers but also created an airfield at Willow Run. This location was chosen because Henry Ford owned the land, which avoided problems with buying land, and it was near roads and rail lines connecting Detroit to Ann Arbor and other areas. Land was acquired from owners in Ypsilanti Township for the Liberator plant and later the airport terminal.

Although Henry Ford was officially retired, he still influenced company decisions. He refused government money to build Willow Run, instead having Ford build the factory and sell it to the government, which would rent it back during the war. Ford had the right to buy the plant after the war ended, but it did not use this option. A story claimed Ford planned to use the site as a tractor factory after the war, but this never happened. In July 1944, Ford sold the land to the Reconstruction Finance Corporation’s Defense Plant Corporation after the Ford farms were transferred to the company.

Architect Albert Kahn designed the main building of the Willow Run bomber plant. The factory had 3,500,000 square feet of space and an aircraft assembly line over a mile long. It was considered the largest factory under one roof in the world. The plant had four large turntables along the assembly line, allowing B-24 production lines to turn 90 degrees before final assembly. Some people believe this design helped Ford pay lower taxes to Washtenaw County instead of Wayne County, where the airfield was located. Overhead views also suggest avoiding the airfield’s taxiways was another reason.

Because so many people moved to the area for work, there was a shortage of housing. The Federal Public Housing Administration built temporary homes to address this need. These homes were built in several areas. Willow Run Lodge was a series of dormitories for single workers, located north of Michigan Avenue and south of Geddes Road. It covered 2,641 acres and included 15 buildings with 1,900 rooms, enough space for 3,000 people.

Between June and December 1943, temporary "flat-top" buildings were built for 2,500 families. This area was called Willow Run Village. The flat-tops had apartments with one, two, or three bedrooms. West Court, another part of Willow Run Village, had apartments with peaked roofs for couples or three adults. Some apartments had no bedrooms and were called "zero bedroom" units. West Lodge, another dormitory with 1,960 rooms, was also completed in 1943.

By the end of 1943, six temporary housing projects were built near Willow Run: two dormitory projects, two trailer projects (one for rented trailers and one for privately owned trailers), and two apartment projects (West Court and Willow Run Village). Together, these projects provided shelter for more than 15,000 people, about the same number of people living in Ypsilanti at the time.

In 1943, Parkridge Homes was built to house African-American workers at Willow Run. Efforts to include African-American residents in other housing projects were refused by the Detroit Housing Commission and the National Housing Agency. African-American architect Hilyard Robinson was hired to design an 80-unit community for them. Parkridge Homes remained as public housing until 2016, when it was demolished and replaced with modern units. In 2017, the Michigan State Historic Preservation Office honored Parkridge Homes with historic markers recognizing its importance to Ypsilanti’s history.

The Parkridge Community Center was also built at the same time. In 1952, sociologist Lowell Juilliard Carr and James Edson Stermer of the University of Michigan wrote a book about the social conditions at Willow Run caused by the sudden increase in workers during the war. They discussed "cultural inadequacy theory," explaining that industrial culture does not provide clear rules for when a manufacturer should build housing and other services or rely on others to do so.

Liberator production

Even though Ford's production executive, Charles E. Sorensen, worked hard to design the plant, problems still happened when it opened. Some workers made mistakes, and the quality of the planes was not always good at first. The Ford Trimotor had been successful in the 1920s, but Ford had not worked on airplanes for a long time. At first, Ford was asked to make parts for the B-24 bomber, which would be finished by other companies in Texas and Oklahoma. However, in October 1941, Ford was allowed to build complete B-24s at its new Willow Run plant. Within a year, finished planes left the factory. This was a surprising achievement for building and starting a new factory.

According to Max Wallace, Air Corps Chief General "Hap" Arnold told Charles Lindbergh, a consultant at the plant, that soldiers preferred the B-17 bomber over the B-24 because "most B-17s return from missions, but most B-24s do not."

A 1943 group created by Congress to study problems at the plant wrote a report that criticized Ford. The company had built a production line that looked too much like an automobile line, even though many experienced airplane workers had warned against this.

Even though Ford faced quality issues because it was an automobile company making airplanes, it also produced planes very quickly. The Willow Run plant was the largest enclosed building in the world. The first Ford-built B-24 rolled off the line in September 1942. The first group of planes made there was the B-24E model.

The Willow Run plant had many problems at the start because Ford workers were used to making cars and had trouble changing their methods for airplane production. The plant also had labor issues, many workers missing work, and people leaving their jobs quickly. The factory was far from Detroit, and wartime rules about gasoline and tires made it hard for workers to get there. In one month, Ford hired 2,900 workers but lost 3,100.

Henry Ford was stubborn and did not like unions. There were serious labor problems, including a big strike. He also refused to hire women at first. However, he finally allowed women to work on the assembly lines, probably because many men had been sent to war rather than because he changed his mind.

By autumn 1943, the top leader at Willow Run was no longer Charles Sorensen but Mead L. Bricker.

At the government's request, Ford spread its work to other plants and companies, with Willow Run focusing on finishing the planes. Over time, the problems in making the planes were fixed, and by 1944, Ford could build a B-24 every 63 minutes, 24 hours a day, 7 days a week.

In April 1944, Willow Run made 428 B-24s in one month. The highest number of planes made in one day was 100 between April 24 and 26, 1944. By 1945, Ford produced 70% of all B-24s in two 9-hour shifts. Ford built 6,972 of the 18,482 total B-24s and sent 1,893 "knock down" kits to be assembled by Consolidated in Fort Worth, Texas, and Douglas Aircraft in Tulsa, Oklahoma. The B-24 was the most produced heavy bomber in history.

After the planes were built, they were sent to military squadrons at Willow Run by the 1st Concentration Command. This group organized and equipped the squadrons before they left for war. It also checked the planes, made final changes like adding fuel tanks, and tested them for safety.

While planes were being prepared, soldiers assigned to each plane were also being trained. Pilots, co-pilots, navigators, and crew chiefs slept on 1,300 cots while waiting for planes to be built. Paperwork was completed, equipment was given out, and training for supporting the planes was done.

Once production started, it was hard to change the planes based on what soldiers needed in battle. So, new planes had to be modified after they were built to match the needs of different regions. Seven centers were created to make these changes: the Birmingham Air Depot in Alabama, Consolidated's Fort Worth plant, the Oklahoma City Air Materiel Center, the Tucson Modification Center, the Northwest Airlines Depot in Minneapolis, the Martin-Omaha plant, and the Hawaiian Air Depot at Hickam Field. The Birmingham Air Depot mainly worked on planes from Willow Run.

The B-24E was the first version of the B-24 made at Willow Run. Ford built 490 planes and sent 144 and 167 kits to Consolidated and Douglas for final assembly. Planes built at Ford were called B-24E-FO, while those assembled elsewhere were called B-24E-DT and B-24E-CF. Because of delays, most B-24Es were too old when they were finished and were used for training in the United States, not for combat.

The B-24H was the first version made in large numbers at Willow Run that went to war. It had a new nose turret to improve defense. The first B-24Hs were delivered late in 1943, and 1,780 were built at Willow Run.

When the B-24J was introduced, all three B-24 production plants switched to making this version. It had a hydraulically powered tail turret and other changes to improve defense. Willow Run built 1,587 B-24Js starting in April 1944.

In June 1944, the Army decided that the San Diego and Willow Run plants could meet all future B-24 needs. The Boeing B-29 Superfortress was now taking over long-range bombing in the Pacific, and no new B-24 units were planned for other war areas.

The B-24L was the first

Post-war conversion

Although Ford had the chance to buy the Willow Run plant after it was no longer needed for wartime production, the company chose not to purchase it and ended its connection with the facility.

After Ford refused to buy the plant, it was sold to the Kaiser-Frazer Corporation, a partnership between construction and shipbuilding leader Henry J. Kaiser and Graham-Paige executive Joseph W. Frazer. The plant made both Kaiser and Frazer car models, including the compact Henry J, which was sold with small changes through Sears-Roebuck as the Allstate.

From 1947 to 1953, Willow Run produced 739,000 cars for Kaiser-Frazer and Kaiser Motors. After years of financial losses, the company (now called Kaiser Motors after Frazer left the partnership) bought Willys-Overland and moved its production at Willow Run to a Willys plant in Toledo, Ohio.

During the Korean War, Kaiser-Frazer built C-119 Flying Boxcar cargo planes at Willow Run under a license from Fairchild Aircraft, producing about 88 planes between 1951 and 1953. To access a military contract for the C-123 Provider transport plane, Kaiser bought half of Chase Aircraft. Senate investigations found that Kaiser’s C-119 planes cost much more than Fairchild’s. The C-123 contracts were canceled by the USAAF, and no completed planes were used.

Near the airport, a group of World War II hangars was sold to the University of Michigan in 1946. The university operated the Michigan Aeronautical Research Center (MARC), later known as Willow Run Laboratories (WRL), from 1946 to 1972. MARC and WRL made important discoveries, such as the first ruby laser, the ruby maser, early research on antiballistic missile defense, and advanced remote sensing.

In 1972, the university separated WRL into the Environmental Research Institute of Michigan, which later moved to offices in Ann Arbor.

In 1953, after a fire destroyed General Motors’ Detroit Transmission factory in Livonia, Michigan, the Willow Run complex was first leased and later sold to GM. Equipment from the damaged factory was moved to Willow Run and returned to production within nine weeks.

Over time, GM expanded the bomber plant by about half, turning it into a nearly 5,000,000-square-foot GM Powertrain factory and engineering center. A nearby area was used for assembly starting in 1959, with a Fisher Body plant that built bodies for Chevrolet models like the Corvair and Nova. In 1968, General Motors reorganized its body and assembly operations into the GM Assembly Division (GMAD). It took 16 years for GMAD to fully take over Fisher Body’s operations, and Fisher Body continued making car bodies at Willow Run until the 1970s. Vehicles were produced there until 1992.

In addition to making automatic transmissions, Willow Run Transmission also made the M16A1 rifle and the M39A1 20mm autocannon for the US military during the Vietnam War.

By 2009, when General Motors went bankrupt, most manufacturing and assembly work at Willow Run had nearly stopped. The GM Powertrain plant closed in December 2010, and the complex was handed over to the RACER Trust, which is responsible for cleaning up the site, preparing it for new uses, and eventually selling the land.

Postwar

Ford built the factory and sold it to the government. Ford then rented it back from the government for the length of the war. After the war ended, Ford did not buy the factory. The Kaiser-Frazer Corporation then became the owner. In 1953, Ford’s competitor, General Motors, bought the factory and used it as Willow Run Transmission until 2010. Willow Run Assembly operated from 1959 to 1992 on land near the airport. The Fisher Body division also worked at Willow Run Assembly until the 1970s, when its tasks were taken over by the GM Assembly Division. In 2009, General Motors said it would close all operations at the GM Powertrain plant and engineering center in the following year.

After Willow Run Transmission closed in 2010, the RACER Trust took control of the factory complex. This group manages properties that were once owned by General Motors. In 2011, A.E. Equities Group Holdings offered to buy the old Powertrain plant from the RACER Trust. In April 2013, a redevelopment manager for the RACER Trust said parts of the Powertrain plant that were not used would likely be torn down as part of redevelopment plans. Most of the plant was demolished in late 2013 and early 2014. In 2014, the Yankee Air Museum moved into the building that once made bombers.

In November 2016, the RACER Trust sold Willow Run to a group created by the State of Michigan. This group now rents the property to the American Center for Mobility (AMC).

The Willow Run complex is also the name of a community on the east side of Ypsilanti. This area is roughly defined by the old boundaries of the Willow Run Community School District.

Redevelopment efforts and the Yankee Air Museum

Since 2004, the airfield has been owned by the Wayne County Airport Authority. It continues to operate as Willow Run Airport and is mainly used for cargo and general aviation flights. The Yankee Air Museum is located on the airport grounds and occupies a 47,000-square-foot (4,400 m²) hangar and other properties as of April 2013.

Before the demolition of Willow Run Assembly, parts of the building were used as a warehouse. About a quarter of this space was leased by General Motors (GM) for parts distribution.

In April 2013, the Detroit Free Press reported that RACER Trust, the current owner of the facility, was discussing with the Yankee Air Museum plans to preserve a small part of the original bomber plant as a new museum location. The museum was originally given until August 2013 to raise funds needed to buy and separate a portion of the approximately 5,000,000-square-foot building, which later became the GM Powertrain facility. The museum would combine its operations currently spread across different areas of Willow Run, and the Trust planned to clear the rest of the plant for redevelopment. The 175,000-square-foot (16,300 m²) section of the original bomber plant that the museum wants to preserve is less than 5% of the entire facility. This section is located at the far eastern edge of the property, at the end of the former B-24 assembly line, and includes the two iconic bay doors through which B-24 Liberator bombers were sent out during World War II.

The campaign to save part of Willow Run for the museum was named SaveTheBomberPlant.org and was centered on a fundraising website with the same name. The campaign received attention from national and international media, including major U.S. newspapers, National Public Radio, The History Channel magazine, National Geographic TV, The Guardian, and the Daily Mail.

RACER Trust extended the original fundraising deadline (August 1, 2013) three times after the museum launched its campaign. The first two extensions were to October 1, 2013, and then to November 1, 2013. On October 26, 2013, RACER Trust and the museum reached a third and final agreement, giving the museum until May 1, 2014, to raise $8 million. Most of this amount would cover costs to separate the preserved section of the plant so it could function as a standalone structure. RACER Trust supported the campaign and adjusted engineering and demolition plans to reduce costs for the museum.

By May 1, 2014, the museum had raised over $7 million of its $8 million goal. This amount was enough for the building’s owners to sign a Purchase Agreement with the museum, with the actual purchase expected to be completed in late summer or fall of 2014.

Meanwhile, the remaining part of the Willow Run property, which includes over 95% of the historic bomber plant building, was offered to Walbridge, Inc., for redevelopment as a connected car research and test facility. However, the option to Walbridge has since expired, and the property remains available for purchase and redevelopment.

Decommission and demolition

In early 2013, Michigan Live reporter Amy Biolchini visited the empty Willow Run facility and noted the following:

During the tour, the group discovered a hidden room inside the building.

Demolition of most of the Willow Run facility started in December 2013. The Yankee Air Museum took over about 144,900 square feet of the plant and plans to create a permanent home for the museum. By mid-2014, most of the facility had been torn down and cleared.