As I wrote in this AWIN-subscriber only article, Southwest Airlines is struggling a bit with its vaunted turn times, which it has long highlighted as the shortest in the business. Security requirements and other regulatory changes, and Southwest's move into some congested airports, are two factors. But so, too, are the airline's rising percentage of connecting passengers--which requires more time waiting for checked bags to be loaded--and its recent order of larger capacity aircraft, namely the Boeing 737-800. It just takes more time to clear and load a plane carrying 32 more passengers than any other aircraft that Southwest flies. In fact, Southwest is talking about efforts to reduce its turn time on the 737-800 to 45-55 minutes--yes, 45 minutes! Here's Herb Kelleher in an advertisement in 1982, boasting about turn times of 10 minutes.