The United States Auto Club (USAC) is one of the sanctioning bodies of auto racing in the United States. From 1956 to 1979, USAC sanctioned the United States National Championship, and from 1956 to 1997 the organization sanctioned the Indianapolis 500. USAC serves as the sanctioning body for a number of racing series, including the Silver Crown Series, National Sprint Cars, National Midgets, Speed2 Midget Series, .25 Midget Series, Stadium Super Trucks, and Pirelli World Challenge. Seven-time USAC champion Levi Jones is USAC's Competition Director.
American open-wheel car racing, generally known as Indy car racing, or more formally Indianapolis car racing, is a category of professional automobile racing in the United States. As of 2024, the top-level American open-wheel racing championship is sanctioned by IndyCar. Competitive events for professional-level, open-wheel race cars have been conducted under the auspices of various sanctioning bodies, tracing its roots as far back as 1902. A season-long, points-based, National Championship of drivers has been officially recognized in 1905, 1916, and each year since 1920. As such, for many years, the category of racing was known as Championship car racing. That name has fallen from use, and the term Indy car racing has become the preferred moniker.
The 1971 USAC Championship Car season consisted of 12 races, beginning in Rafaela, Argentina on February 28 and concluding in Avondale, Arizona on October 23. The USAC National Champion was Joe Leonard and the Indianapolis 500 winner was Al Unser. For 1971 it was decided that there should be three separate points championships, for paved ovals, dirt ovals, and road courses.
The 1972 USAC Championship Car season consisted of ten races, beginning in Avondale, Arizona on March 18 and concluding at the same location on November 4. The USAC National Champion was Joe Leonard and the Indianapolis 500 winner was Mark Donohue. Jim Malloy was killed at Indianapolis in practice; he was 40 years old.
The 1973 USAC Championship Car season consisted of 16 races, beginning in College Station, Texas on April 7 and concluding in Avondale, Arizona on November 3. The first race of the season, in Avondale, Arizona on March 17, was postponed by rain and eventually cancelled due to infrastructure damage caused by the rain and scheduling conflicts. Bob Criss was killed in a private test at Phoenix before he could enter another event. He was 35 years old. The USAC National Champion was Roger McCluskey and the Indianapolis 500 winner was Gordon Johncock.
The 1975 USAC Championship Car season consisted of 13 races, beginning in Ontario, California on March 2 and concluding in Avondale, Arizona on November 9. The USAC National Champion was A. J. Foyt and the Indianapolis 500 winner was Bobby Unser.
The 1976 USAC Championship Car season consisted of 13 races, beginning in Avondale, Arizona on March 14 and concluding at the same location on November 7. The USAC National Champion was Gordon Johncock and the Indianapolis 500 winner was Johnny Rutherford.
The 1977 USAC Championship Car season consisted of 14 races, beginning in Ontario, California on March 6 and concluding in Avondale, Arizona on October 29. The USAC National Champion was Tom Sneva and the Indianapolis 500 winner was A. J. Foyt. The schedule included a road course for the first time since 1970.
The 1978 USAC Championship Car season consisted of 18 races, beginning at Phoenix on March 18 and concluding at the same location on October 28. The USAC National Champion was Tom Sneva and the Indianapolis 500 winner was Al Unser. This was the last year before the first USAC/CART "Split". By winning the Indianapolis 500, Pocono 500, and California 500, Al Unser swept the Indy car "Triple Crown", the only driver in history to do so.
The 1979 USAC Championship Car season consisted of seven races, beginning in Ontario, California on March 25 and concluding in West Allis, Wisconsin on August 12. The USAC National Champion was A. J. Foyt and the Indianapolis 500 winner was Rick Mears. With the exception of the Indianapolis 500, most top drivers instead competed in races sanctioned by CART.
The 1980 USAC Championship Car season consisted of five races, beginning in Ontario, California on April 13 and concluding in Lexington, Ohio on July 13. The USAC National Champion and Indianapolis 500 winner was Johnny Rutherford.
The 1970 USAC Championship Car season consisted of 18 races, beginning in Avondale, Arizona on March 28 and concluding at the same location on November 21. There was also one non-championship event at Pikes Peak, Colorado. The USAC National Champion and Indianapolis 500 winner was Al Unser. After this season, dirt courses did not reappear in the USAC Championship until 1981-82. Road courses after this season did not reappear in the USAC Championship until 1977. The Pikes Peak Auto Hill Climb was the only non-championship event.
The 1956 USAC Championship Car season consisted of 12 races, beginning in Speedway, Indiana, on May 30 and concluding in Phoenix, Arizona, on November 12. There were also three non-championship events. The USAC National Champion was Jimmy Bryan and the Indianapolis 500 winner was Pat Flaherty. This was the first year that the National Championship was sanctioned by the USAC, after the withdrawal of the AAA from all forms of racing after the 1955 season.
The 1955 AAA Championship Car season consisted of 11 races, beginning in Speedway, Indiana on May 30 and concluding in Phoenix, Arizona on November 6. There was also one non-championship event in Mechanicsburg, Pennsylvania. The AAA National Champion and Indianapolis 500 winner was Bob Sweikert. Manny Ayulo was killed at Indianapolis while practicing for the 1955 Indianapolis 500, and Bill Vukovich, the two-time defending winner, was killed in the race itself. Jack McGrath, the two-time champion, was killed in the final race at Phoenix on lap 85. This was the last year of the AAA National Championship; USAC sanctioned the series starting the next year.
The 1941 AAA Championship Car season consisted of three races, beginning in Speedway, Indiana on May 30 and concluding in Syracuse, New York on September 1. There was also one non-championship event held at Langhorne, Pennsylvania. The AAA National Champion was Rex Mays and the Indianapolis 500 co-winners were Floyd Davis and Mauri Rose - the second such occasion in history. The National Championship was not held again until 1946, due to World War II.
The 1940 AAA Championship Car season consisted of three races, beginning in Speedway, Indiana on May 30 and concluding in Syracuse, New York on September 2. There was also one non-championship event in Langhorne, Pennsylvania. The AAA National Champion was Rex Mays and the Indianapolis 500 winner was Wilbur Shaw.
The 1939 AAA Championship Car season consisted of three races, beginning in Speedway, Indiana on May 30 and concluding in Syracuse, New York on September 2. There was also one non-championship event in Springfield, Illinois. The AAA National Champion and Indianapolis 500 winner was Wilbur Shaw.
The 1938 AAA Championship Car season consisted of two races, beginning in Speedway, Indiana on May 30 and concluding in Syracuse, New York on September 10. There were also two non-championship events. The AAA National Champion and Indianapolis 500 winner was Floyd Roberts.
The 1954 AAA Championship Car season consisted of 13 races, beginning in Speedway, Indiana on May 30 and concluding in Las Vegas, Nevada on November 14. There was also one non-championship event in Mechanicsburg, Pennsylvania. The AAA National Champion was Jimmy Bryan, and the Indianapolis 500 winner was Bill Vukovich. Bob Scott was killed in the Independence Day Sweepstakes race at Darlington.
The 1946 AAA Championship Car season was the first season of American Championship car racing following World War II. After four years without automobile racing in the United States, the AAA Contest Board was initially concerned about having enough races, enough entrants, and suitable equipment, to contest season on such short notice for 1946. Even the Indianapolis 500 was in doubt, as the Indianapolis Motor Speedway had been fallen into a terrible state of neglect during the war years.
Bobby Unser 
