CHICAGO — Struggling U.S. airlines, looking for new ways to generate revenue, are getting bolder about charging for pretty much anything that makes air travel a little more comfortable — including aisle seats. First came charging passengers for in-flight meals. Then, reservations done by phone cost extra. And now, one major airline, Northwest Airlines Corp. , is trying to charge passengers for the right to sit in aisle seats and emergency-exit rows. The day is coming when carriers will require special fees even to check a bag, experts say. Analysts told Reuters that travelers should brace for more nickel and diming as airlines seek to recoup losses from soaring fuel costs and competitive pressures. Airlines are likely to test passengers’ willingness to pay for an ever wider array of services. “We’re just scratching the surface. I think 2006 is going to bring a tremendous amount of changes,” said Terry Trippler, an analyst with travel Web site Cheapseats.com. “I think it’s going to be the difference between a black bottom line and a red one,” he said. Bankrupt Northwest this week unveiled a program called Coach Choice in which the carrier will save some preferred […]