The Tonopah Army Air Field was activated and ready for occupancy in July 1942, the airbase included runways, barracks, mess halls and a hospital.
In September 1943 the base was shut down to expand for Consolidated B-24 Liberator training. By October 1943, about half of the personnel were moved temporarily to Bishop Army Air Field, California, in order to provide housing at Tonopah for construction contractors on a $3,000,000 project. Most construction was complete by the beginning of November 1943, and training facilities included a rifle range, pistol range, skeet ranges, turret trainers, bomb trainers equipped with Norden or Sperry sights, flexible gunnery trainers, navigation trainers, and schools for gunners and radio operators. Personnel at Bishop returned on November 1, 1943, and the 458th Bombardment Group arrived for training. When the 458th departed in January 1944, the 470th Bombardment Group arrived at Tonopah as a B-24 replacement training unit. In a March 31, 1944, reorganization the 470th was disbanded and its training functions being taken over by the 442nd Army Air Force Base Unit.
In the summer of 1944, a Field Test Unit of Wright Field's Special Weapons Branch* tested guided bombs (e.g., GB-4, GB-6 and the GB-8). The post exchange that had opened in August 1942 paid a 13 November 1943 dividend of $10,741.48, and the base's large bakery during 1943 and 1944 sold an average of 400 dozen doughnuts a day. In October, 1944, there were 66 B-24 aircraft available for the training program and there were 1,264 officers and 5,273 enlisted men assigned to the base (437 officers, 3,707 enlisted men, and 184 civilians by March 1945).