Randolph Air Force Base, about fifteen miles northeast of San Antonio, was identified as the "West Point of the Air" when it was officially dedicated on June 20, 1930. Beginning as a primary and basic flying training base, the Central Instructor’s School began in the mid-1940s, and ever since then, teaching pilots to instruct undergraduate pilots has been a major part of Randolph’s mission. The idea for Randolph came soon after the enactment of the Air Corps Act of 1926. The Act changed the name of the Army Air Service to the Army Air Corps, provided a five-year expansion program for the under-strength Air Corps, and established two new brigadier general positions for the Army. One of these new positions placed a general officer in charge of all flying training for the Air Corps. Brig. Gen. Frank P. Lahm (later known as "the father of Randolph Field") was selected to fill this position, which proved to be a pivotal event in the history of Randolph Air Force Base. Once placed in charge of flying training, General Lahm established the Air Corps Training Center at Duncan Field, adjacent to Kelly Field (see KELLY AIR FORCE BASE). Soon thereafter he realized that the Air Corps training requirements had become too great for Brooks and Kelly fields, and that another field dedicated to flying training was needed—preferably in an area in which San Antonio's rapid growth would not hinder the training operations. The initial site chosen for the new field was a place known as Calf Hill, less than ten miles east of the city on Hedwig Road, just south of the site of the Woodlake Country Club. An essential tract of land owned by William Rittiman, however, could not be obtained, so General Lahm dismissed the site. Around November 1927, nineteen sites for the new airfield were submitted to General Lahm for his consideration. Finally, a 2,300-acre tract near Schertz was decided upon for the new field.
In mid-August 1928 the land near Schertz was given to the United States government. The city of San Antonio raised the money for the land by passing an ordinance authorizing $500,000 in city notes, which were backed by delinquent taxes owed to the city. To keep taxpayers from holding a lien on the land, the Airport Company obtained loans from various area banks, which allowed the company to purchase the land and give it to the city. The city of San Antonio then paid off the company's note with the money received from the back taxes. Before and during the search for a new training field, a young first lieutenant named Harold Clark was busy designing his ideal "Air City" on the back of dispatch sheets while assigned as a dispatch officer at the Kelly Field motor pool. Before entering the U S. Army, Lieutenant Clark had trained as an architect. When he learned that the new field was to be built, Clark took his drawings to General Lahm, who was so impressed with his designs that he had Clark detailed on special duty to his office so he could work full-time on developing his design. At the time, the Randolph Field project was the largest construction project undertaken by the United States Army Corps of Engineers since the Panama Canal. It took more than five years—from 1928 to 1933—to construct the 500-plus Spanish Colonial Revival-style buildings and the thirty miles of roadways. In the end, the buildings of the base were centered on the field, with the administration building providing the perfect centerpiece. The base streets were laid out concentrically, and the aircraft ramps and runways on the east, west, and south portions of the base formed a square perimeter around the circular layout of the field. After the site for the new field was selected, a committee decided to name the base after Capt. William Millican Randolph, a native Texan and a graduate of Texas A&M. The captain was killed on February 17, 1928, when his AT-4 crashed on takeoff from Gorman Field in Texas. Ironically, Captain Randolph had been a member of the committee assigned to select a name for the new airfield.
On June 20, 1930, Randolph Field was formally dedicated as a crowd of more than 15,000 looked on. Mrs. William M. Randolph, escorted by General Lahm, raised the first flag over the base, and the ceremony concluded with 233 planes from four military installations (Brooks and Kelly fields, Fort Crockett and Fort Sill) conducting a flyby of the field in what had been advertised as "the largest assembly of aircraft in the world." On November 2, 1931, the Air Corps Primary Flying School was officially established. Primary training continued at Randolph until 1939, when the mission was changed to basic pilot training. Cadet training continued until March 1943, when it was replaced with the Central Instructors School. For the next three years the mission at Randolph was training instructors for all three phases (basic, primary, and advanced) of the Air Corps' flying training program. During this time, the Central Instructors School managed to train 15,396 pilots as instructors. In April 1945 the Central Instructors School was replaced by the Army Air Force Pilot School, which specialized in transition training for B-29 bomber pilots, copilots, and engineers. From December 1945 to March 1948 primary and basic pilot training was conducted at Randolph. In March 1948 the primary pilot training program was deleted, and in August the 3510th Basic Pilot Training Wing became the host unit at Randolph. In September 1947 the Air Force had become a separate service; the term "Field" was dropped from Randolph, and Air Force Base was added in its place four months later, on January 13, 1948.
In July 1957, Air Training Command moved to Randolph from Scott Air Force Base, Illinois. During 1959 the base saw its Seguin Auxiliary Field open and the School for Aviation Medicine end its twenty-eight-year tenure at Randolph when it was moved to Brooks Air Force Base. On May 1, 1972, the Twelfth Tactical Fighter Wing was redesignated the Twelfth Flying Training Wing and then activated at Randolph Air Force Base. Since that time, the wing has served as host for the following headquarters: Air Training Command (now Air Education and Training Command), Air Force Military Personnel Center, Air Force Civilian Personnel Management Center, Air Force Recruiting Services, and the Air Force Management Engineering Agency, as well as more than twenty tenant organizations. In the early 1990s more than 8,000 personnel, including more than 3,000 civilian workers, were employed at the base, which had an annual payroll of more than $277 million.
With its activation in May 1972, the Twelfth Flying Training Wing became the host wing, continuing the mission of training pilots to be instructor pilots. Shortly after the Vietnam War, the wing's mission temporarily expanded to include T-37, T-38, and T-39 pilot requalification training (Operation Homecoming) for more than 150 United States Air Force ex-prisoners of war. Project homecoming began on May 2, 1973, and lasted until November 12, 1976. From 1976 until December 1992, the flying mission at Randolph was solely pilot instructor training. This changed with the adoption of the navigator mission in 1993, the addition of fighter fundamentals training, and a limited airlift mission (until 1997). The 12th Flying Training Wing was also reorganized into an “objective wing,” utilizing the one base, one wing, one boss principle. A new airplane, the Texan II, began testing at Randolph by June of 1999; it replaced the T-37 in 2007. The 2000s was a decade of new ideas. The wing prepared for the Joint Base concept, changed its navigator training to Combat Systems Officer training, and adopted a new mission of the basic training of Remotely Piloted Aircraft pilots and Basic Sensor Operators in 2009. In 2010, after thirty-eight years as Randolph AFB’s host wing, the 12th Flying Training Wing became a tenant unit of the new Joint Base San Antonio (JBSA). The 502d Air Base Wing, headquartered at Fort Sam Houston, became the new host wing for JBSA.