 Combined, this airline operated the largest fleet of Tri-motors at the time, including seven 5-AT's and several more 4-AT's, carrying 40,000 passengers in 1929.In 1930 TAT-Maddux merged with its former competitor Western Air Express to form Transcontinental & Western Air (T&WA), which later became TWA.On April 21, 1929 a Maddux Air Lines Ford 5-AT-B Tri-motor was involved in a midair collision with a single-engine U.S. Army Boeing PW-9D pursuit biplane near San Diego.