Straub earned his amateur radio license in 1931. Then, in 1937, he began working as a control tower operator and assistant airport manager at Lambert Field in St. Louis. In these early days, a tower operator’s equipment included a wheel barrow, flags, and an umbrella which were moved from one end of the runway to the other to signal incoming and outgoing aircraft. Straub moved to Wichita in 1941 to become manager of the new Municipal Airport. Here, he supervised capital improvements including a new state-of-the-art control tower and the addition of two wings on the terminal building for the U.S. Army. In 1944, with Beech, Cessna and Stearman, Trans World Airlines, Braniff and Continental Airlines making daily flights, the Wichita Airport (under Charlie’s management) was the fourth busiest airport in the country.