Southern Air Transport (1929) Wikipedia
Southern Air Transport, based in Dallas, Texas, was formed on February 11, 1929 when businessman A. P. Barrett consolidated Texas Air Transport and several other small aviation companies. Later that year SAT came under the control of the Aviation Corporation, the company that organized American Airlines.
SAT was awarded CAM 29, the U.S. Postal Service route from New Orleans to Houston, in January 1929.