Wendover Airfield in Utah served as the primary training and testing center for the atomic bomb delivery group during the Manhattan Project, according to records from the Atomic Heritage Foundation and the National Park Service. The remote location provided the isolation required for the highly classified Project W-47 missions aimed at ending World War II.
The Secret 509th Composite Group
In September 1944, Lieutenant Colonel Paul Tibbets was selected to lead a secret mission to prepare modified B-29 bombers and their crews for atomic bomb delivery. Tibbets chose Wendover Airfield over sites in Kansas or Idaho because of its remote location, functional hangars, and a rail line that allowed for the delivery of sealed shipments.
The unit, designated the 509th Composite Group, was a self-contained entity that included pilots, maintenance personnel, and administrative staff. To maintain maximum security, the unit was code-named "Kingman" and functioned as the Manhattan Project's Site K. According to the National Park Service, members of the group were instructed to keep the true nature of their mission secret, with mail and phone calls being monitored to ensure total security.
Training for Atomic Delivery
The training at Wendover focused on mastering the unique ballistics and flight characteristics of the new atomic weapons. To prepare for the weight and shape of the real bombs, crews utilized dummy weapons known as "pumpkin bombs." These practice munitions were often painted orange and were filled with concrete or high explosives to simulate the characteristics of the "Fat Man" design.
Bombardiers practiced precision drops from altitudes of 30,000 feet, aiming for a target circle only 400 feet in diameter. Tibbets required crews to complete 50 practice drops before they were considered combat ready. A critical component of the training involved perfecting the "escape maneuver," a high-throttle, 155-degree turn performed immediately after bomb release to move the aircraft away from the detonation zone.
Collaboration with Los Alamos
The partnership between the airfield and Los Alamos scientists was essential to the success of the mission. Under the designation Project W-47, the Flight Test Section and Special Ordnance Detachment worked with scientists to test prototype bombs. These tests gathered vital data on electrical fusing, detonators, and release mechanisms.
To facilitate these tests, specialized pits equipped with hydraulic lifts were constructed to hoist the massive bombs into the aircraft bomb bays. Between October 1944 and August 1945, a total of 155 test units were dropped on targets surrounding the Wendover airfield to refine the weapon configurations.
Strategic Importance of Wendover
Wendover's selection as a training hub was driven by its geographic advantages. Established in 1940 to meet Army needs for bombing ranges, the site featured vast, uninhabited land and excellent flying weather. The location was also easily accessible via the Western Pacific Railroad, which serviced the area with multiple lines running from Salt Lake City to the West Coast.
At its peak, the base was a massive operation, hosting 2,000 civilian employees and 17,500 military personnel. The facility included 668 buildings, three 8,100-foot runways, and a variety of specialized structures including barracks, officer quarters, a theater, and a medical facility.
Legacy and Preservation
Following the conclusion of the war, the 509th Composite Group moved to Tinian Island in June 1945. After their service in the Pacific, the unit was assigned to Roswell Army Airfield in New Mexico, where it became the nuclear strike core of the Strategic Air Command.
Today, Wendover Airfield is recognized as an authentically preserved WWII Army Air Forces training base. While portions of the original bombing range are now used by the Air Force as the Utah Test and Training Range, the airfield remains a public airport and a site for historical tours and air shows.
The Broader Manhattan Project
The Manhattan Project's footprint in the region extended beyond Wendover. While Wendover served as the training site, other locations like Los Alamos, New Mexico, and Hanford, Washington, played critical roles in the development and production of the atomic bomb components.
