http://www.slate.com/id/2297293/ The crew on a U.S. Airways flight out of San Francisco demanded that a passenger pull up his low-slung pants on Wednesday before takeoff—because they exposed his underwear. When the passenger refused and reportedly turned belligerent, the captain conducted a citizen's arrest and called the police. Can a flight attendant tell you what to wear? In most cases, yes. All major airlines have granted their flight crews the authority to ask a passenger to cover up or leave the plane. But they offer very little guidance as to what sorts of attire are unacceptable. Some airlines have no written dress code at all. Others, like American Airlines, are vague about it, forbidding clothing "that would cause discomfort or offense to other passengers." (They do explicitly ban bare feet.) So there's really no way of knowing if your low-slung pants, spaghetti-strap top, or miniskirt are going to get you bounced from your flight. The FAA has no rules or regulations regarding passenger garb.