[2] It began scheduled service on the St. Louis - Cincinnati - Dayton - Toledo - Detroit route on May 14, 1938, with service four days a week, which soon expanded to six days a week, using Stinson Model A tri-motor aircraft.
TWA saw the airline as a potential competitor and opposed Marquette's application for an operating certificate.
[1] TWA agreed to acquire Marquette in October 1939, subject to CAA approval.
[3] But between then and July 3, 1940, when the acquisition was denied, the airline regulatory functions of the CAA had become the Civil Aeronautics Board (CAB), which said, regarding TWA's application to purchase Marquette for US$350,000, that "it would be clearly adverse to the public interest" for Marquette's operating certificate "to be treated as if it were a speculative security.
[10] The CAB announced on October 18, 1941, that TWA could formally acquire Marquette, by which time the airlines were merged in all but name.