Many of the early airlines in this part of the world used classic western or American Indian images in their logos and advertising, but few did it as well as Western Air Lines in its early years. Starting out as Western Air Express, the company acquired National Parks Airways in 1937 and inherited its north-south route through Montana. They acquired Inland Air Lines in 1944, adding Inland's route from Great Falls to Lewistown, Billings, and beyond.
Whoever designed the old Western Air Lines timetables must have been a fan of the Great Northern Railway, since the Indian Chief artwork is strongly reminiscent of the GN's promotional material of the era. It was much classier than the cartoon bird that Western used in its TV advertisements when I was a kid ... though I have to confess that I quite liked that, too.