The airport was established in August 1942 at the beginning of
World War II, and was used as an air support command base as part of the Desert Training Center in the
Mojave Desert of
Southern California. The mission of the training center was to prepare United States Army ground forces in preparation for
Operation Torch—the invasion of
North Africa. The center was commanded by General
George Patton. The airfield was known as
Thermal Ground Support Base or
Thermal Army Air Field. The facility had two runways and assigned the installation to
Fourth Air Force. Between March 1943 and May 1944, the
U.S. Army Air Forces assigned the
76th Reconnaissance Group along with several liaison and tactical reconnaissance squadrons to the airfield. In December 1943, Thermal AAF was reassigned to the California–Arizona Maneuver Area under control of the
Third Air Force. Located in the
Coachella Valley below sea level, the area was named Thermal due to the area's high temperatures, with summer readings of in the shade. Summer flight operations took place from 0300 to 1300 to combat the daytime heat, with no servicing performed during the middle of the day. In addition to flying operations, the station served as a pre-embarkation training center for aviation, construction, ordnance and other units. Phased down in 1944 after most Army units had deployed overseas to combat areas, Thermal had been inactive for six months when the
United States Navy requested permission to occupy the base on December 2, 1944, with the stipulation that the Army could reoccupy with 30 days' notice. Initially known as
Naval Air Bases Detachment Thermal, the base's facilities were in rather poor condition. During the first few months of the Navy's occupancy,
ACORN (Aviation Construction, Ordnance and Repair - Navy) units and
Seabees made extensive improvements. The airfield had a maximum capacity of 2,424 enlisted men and 264 officers. A hospital was located at the facility and had a maximum capacity of 119 patients, 68 nurses, 13 officers, and 16 enlisted men. There were approximately 254 buildings consisting of 237 military buildings built by the
War Department and 17 non-military buildings (present at the time of base acquisition). The airfield was improved with approximately 250 buildings, heating, lighting, telephone, sewer, water and power systems. NAB Thermal provided pilot refresher training and aircraft strength reached 115, including the
F6F Hellcat,
F4U Corsair,
TBM Avenger,
SB2C Helldiver, and
SBD Dauntless. Station aircraft consisted of a
J4F, an
N2S, an NE, and a GB. The Navy closed Thermal on November 1, 1945, returning the field to the Army two months later. The site was declared surplus effective November 16, 1945, and transferred to the War Assets Administration (WAA) on January 23, 1947. The War Assets Administration turned the military airfield to civil control during 1947 and 1948. Approximately were deeded on June 20, 1947, to United Date Growers of California. Approximately were deeded on September 2, 1947, to Coachella Valley County Water District. On December 21, 1948, it was returned to the County of Riverside via quitclaim deed for use as a municipal airport. == Current era ==