This article from NYTimes.com has been sent to you by psa188@juno.com. Into Thin Air February 17, 2002 By ROGER LOWENSTEIN Airlines have always been a hard business. But a case study of United shows why they have been so extraordinarily successful at making profits disappear. http://www.nytimes.com/2002/02/17/magazine/17AIRLINES.html?ex=1015006885&ei=1&en=73906bc45376aae2 HOW TO ADVERTISE --------------------------------- For information on advertising in e-mail newsletters or other creative advertising opportunities with The New York Times on the Web, please contact onlinesales@nytimes.com or visit our online media kit at http://www.nytimes.com/adinfo For general information about NYTimes.com, write to help@nytimes.com. Copyright 2002 The New York Times Company