As a "Radar (R) Type" bombing range, the Site was utilized primarily as a training area for U.S. Navy aircraft operating from NAAS Crows Landing. These aircraft were equipped with newly developed radar equipment designed to greatly improve the accuracy of low level bombing delivery. Several other naval training facilities in the area, including NAS Alameda, also utilized former Gustine Bombing Range to improve their proficiency with the new technology. Practice bombs and signal devices-rather than live ordnance-were used on this range in support of the radar bombing training.
As the war intensified, a request for advisement regarding the renewal or cancellation of leasehold estates for the fiscal year 1946 was made by a Naval Speedletter dated 21 May 1945. This letter listed former Gustine Bombing Range and included the lessor Simon Newman Company, et al., and Civil No. 5028. Approval of this request for the renewal of the leasehold estates was provided by a letter from the Navy Department, Bureau of Aeronautics, dated 29 June 1945. This letter also certified that the use of the premises was needed and essential to the conduct of the war. Additional approval was indicated in a letter dated 5 June 1945 from the Office of the Chief of Naval Operations.
With Japan's sudden surrender in late 1945, according to a letter from Fleet Air Commander, Alameda, dated February 1946, former Gustine Bombing Range was no longer needed by the U.S. Navy. In a letter dated 16 September 1946 from the Commander of Naval Air Bases, Twelfth Naval District, and endorsed by the Commandant of the Twelfth Naval District, to the Chief of the Bureau of Aeronautics of the Navy Department, former Gustine Bombing Range was reported as clean with no further action required. The report attached to the correspondence also indicated that only 3-pound cast iron and water-filled bombs were used. Another report on the Status of Facilities as of 15 February 1947, by the Naval Air Bases, Twelfth Naval District, lists former Gustine Bombing Range as surplus and indicated that the leases had been canceled as of 25 March and 7 April 1946. When the leases were canceled, the land was returned to the Simon Newman Company.
No as-built maps were found during research. Research indicates that the only DoD improvement on the Site was the bombing target, which comprised a net stretched between eight large poles.
The two leases with Simon Newman Company were canceled as of 25 March and 7 April 1946, and the land was returned to the Simon Newman Company. The Simon Newman Company continued ranching on the Site until it started selling portions of the Site to other private parties in the 1970s. Between 1946 and 1952, the DOI constructed the Delta-Mendota Canal as part of the California Valley Project to supply the Central Valley with water. The Delta-Mendota Canal runs through the northeastern corner of the Site. In the 1960s, the California Aqueduct was constructed through the western portion of the Site within the buffer zone of the bombing target, but not within the target area. Interstate 5 was constructed through the eastern portion of the Site and opened in stages in the 1960s and 1970s. Today, the Site is primarily used for grazing.