Herb Kelleher

Kelleher stepped back as Southwest's chief executive in 2001 and split his role between Colleen Barrett, his long-time right hand who became president, and the lawyer Jim Parker as chief executive, while he stayed chairman. Both had decades inside the airline and understood its low-cost, high-morale model. Southwest stayed profitable through the airline crisis after September 2001, when most rivals lost heavily, which is the real test of the handover.