The Dallas carrier has had only a few CEOs in its 50-year history. It was led for many years by Herb Kelleher, a colorful, chain-smoking lawyer who helped create the airline 50 years ago against fierce opposition from existing carriers. Kelleher stepped down in March 2001, but his successor, Jim Parker, had a tense relationship with labor groups at the heavily unionized airline, and was replaced by Kelly in 2004.
