Budget airline king Bill Franke warms to premium upgrades
Bill Franke, co-founder of Indigo Partners and chairman of Frontier Airlines Inc., speaks during an interview in New York, Oct. 28, 2022. Jeenah Moon | Bloomberg | Getty Images SCOTTSDALE, Ariz. — For decades, William Augustus Franke, Frontier Airlines‘ chairman and a serial airline investor, made a killing selling cheap plane tickets and charging fees…