The North American Aviation Fairfax Plant (B-25 Bomber Plant)

The North American Aviation Fairfax Plant was the largest single Kansas City-area industrial facility of World War II. Built in 1940-1941 in the Fairfax Industrial District of Kansas City, Kansas, it produced 6,608 B-25 Mitchell medium bombers — roughly two-thirds of the 9,816 B-25s built nationwide — and employed as many as 26,000 workers at its wartime peak, about 40 percent of them women by 1944. After the war General Motors took over the plant and converted it to automobile assembly, beginning a postwar industrial run on the Fairfax site that continues today as GM Fairfax Assembly.

[!info] Cornerstone entry This is a Cornerstone article — a flagship, deeply-sourced KS.City wiki entry maintained to an encyclopedic, citation-first standard. The plant’s living automotive successor, GM Fairfax Assembly — now retooling for electric vehicles — has its own page.

Summary

The North American Aviation Fairfax Plant was a federally financed wartime aircraft factory in the Fairfax Industrial District of Kansas City, Kansas, west of the Missouri River and north of the Kaw (Kansas) River. The plant:

• Was announced on December 7, 1940 and built across 1940-1941 at federal direction¹²
• Produced the B-25 Mitchell twin-engine medium bomber from 1941/42 through 1945¹
• Built 6,608 B-25 bombers — about two-thirds of the 9,816 produced nationally¹²
• Reached peak employment of roughly 26,000 workers, around 40 percent of them women by 1944¹²
• Was operated by North American Aviation under federal war-production contract¹
• Anchored Kansas City’s largest single home-front mobilization of the war

After Japan’s surrender ended the bomber contract in 1945, General Motors leased the plant and converted it to automobile production. The site has remained an active automotive plant ever since, today as GM Fairfax Assembly.³⁴

Construction and the WWII home front

Federal authorities announced the Kansas City bomber plant on December 7, 1940 — exactly one year before Pearl Harbor — and selected the Fairfax District for reasons that recurred across the wartime dispersal of American aircraft work:¹²

• Mid-continental location, far from the coasts where planners feared attack
• Rail connections for moving materials and parts
• An existing industrial district with utilities and graded land already in place
• A regional labor pool drawn from both Kansas City, Kansas and Kansas City, Missouri

The Fairfax site sat on level ground beside the Kaw River and adjacent to Fairfax Field, giving the new plant a finished aircraft a runway to fly from. Construction proceeded quickly under wartime urgency, and the plant moved into B-25 production in 1941-1942.¹

B-25 Mitchell production

The B-25 Mitchell, designed by North American Aviation in the late 1930s and named for air-power advocate Billy Mitchell, was the plant’s sole wartime product. The twin-engine medium bomber served in every theater of the war and is best remembered for the April 18, 1942 Doolittle Raid, the first U.S. air strike on the Japanese home islands, when sixteen B-25s launched from the carrier USS Hornet. The Doolittle aircraft were drawn from early North American production; whether any came from the Fairfax line specifically is not established.⁵⁶

Across the war the Fairfax plant built 6,608 B-25s — roughly two-thirds of the 9,816 produced nationwide, the balance coming from North American’s Inglewood, California factory. Fairfax output centered on the later B-25D and B-25J variants.¹² The figure of 6,608 is consistent across the Pendergast Years project and the Kansas City Public Library’s local history record; a closely related figure of 6,680 appears in some accounts.

Workforce and the home front

Employment at the Fairfax plant climbed to roughly 26,000 workers at its wartime peak. One local account records that 59,337 men and women passed through the plant over the full December 1941-August 1945 run, reflecting heavy turnover as well as scale.²

The workforce reshaped the metro’s labor profile:

• Women made up about 40 percent of workers by 1944 — Kansas City’s local face of the “Rosie the Riveter” wartime workforce¹²
• In-migrant workers arrived from rural Kansas, Missouri, and neighboring states
• Black workers found war-industry jobs amid broader wartime migration, intensifying pressure on Kansas City’s segregated housing and on neighborhoods such as those around downtown Kansas City and 18th & Vine

The surge of war workers strained metro-area housing and helped set demographic patterns that carried into the postwar decades.

Postwar conversion to GM Fairfax

Japan’s surrender in August 1945 ended the government’s B-25 contract. Later that year General Motors took over the former bomber plant, and automobile assembly began at the site under GM’s Buick-Oldsmobile-Pontiac Assembly Division.³⁴ In an unusual wartime-civilian hybrid, the plant also built F-84F jet fighters alongside cars in the early 1950s during the Korean War buildup.⁴

GM ran the original WWII building until May 1987, when production shifted to a new $1 billion Fairfax II plant built on the grounds of the former Fairfax Airport; the historic bomber building was later demolished. Fairfax II remains in operation today as GM Fairfax Assembly, one of the metro’s anchor employers — now being retooled for electric-vehicle production.³⁴

Legacy

The Fairfax plant was Kansas City’s single largest contribution to American wartime production and a defining episode of the metro’s home front. Its 6,608 bombers placed Kansas City among the major U.S. aircraft-building centers of the war, alongside Wichita, Long Beach, and Buffalo. The plant’s smooth 1945 handoff from bombers to automobiles became a textbook case of postwar industrial reconversion — and, in continuous operation for more than eighty years, the site remains the longest-running legacy of Kansas City’s wartime industrial mobilization. The other two great Kansas City war plants, the Pratt & Whitney aircraft-engine plant (later the Bannister Federal Complex) and the Lake City Army Ammunition Plant, complete the metro’s WWII production triad.²

Sites in KC associated with the Fairfax Plant

• The Fairfax Industrial District, Kansas City, Kansas — original plant site; still an active industrial and automotive zone
• Fairfax Field / former Fairfax Airport — adjacent airfield; later the footprint of GM’s Fairfax II plant
• GM Fairfax Assembly — the plant’s living automotive successor
• Bannister Federal Complex (south Kansas City, Missouri) — wartime Pratt & Whitney aircraft-engine plant; later the NNSA Kansas City National Security Campus
• Lake City Army Ammunition Plant (Independence, Missouri) — the metro’s third major WWII war-production site

Sources

Footnotes

1. The Pendergast Years (pendergastkc.org), “North American Aviation Plant” — announcement date December 7, 1940; 6,608 of 9,816 B-25s built at Fairfax; peak employment ~26,000; women ~40% of workers in 1944. https://pendergastkc.org/articles/north-american-aviation-plant ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹

2. Kansas City Public Library, Missouri Valley Special Collections / KC History, “Flying High” — Fairfax B-25 production, cumulative 59,337 workers Dec 1941-Aug 1945, women workforce. https://kchistory.org/this-week-kc-history/flying-high ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸

3. Wikipedia, “Fairfax Assembly & Stamping” — postwar GM lease/purchase and conversion to automobile assembly under the Buick-Oldsmobile-Pontiac Assembly Division; original plant operated 1945-1987; $1 billion Fairfax II built on former Fairfax Airport grounds. https://en.wikipedia.org/wiki/Fairfax_Assembly_%26_Stamping ↩ ↩² ↩³

4. GM Authority, “General Motors Fairfax Kansas Plant” — GM lease (1945), F-84F jet-fighter production alongside cars in the early 1950s, closure of original plant 1987. https://gmauthority.com/blog/gm/gm-facilities/gm-usa-facilities/gm-fairfax-kansas-city-kansas-usa-plant/ ↩ ↩² ↩³ ↩⁴

5. North American Aviation / B-25 production history — B-25 Mitchell design and variants (B-25D, B-25J). https://b-25history.org/history/fairfax.htm ↩

6. General histories of the Doolittle Raid (April 18, 1942) — sixteen B-25s launched from USS Hornet; aircraft drawn from early North American production. ↩