(MONEY Magazine) – Forget about frequent-flier miles. U.S. airline passengers today ought to get ! frequent-crier miles -- anything that might compensate them for the pound-the- counter-and-weep disarray that so often seems to mark U.S. air travel. Cost cutting, consolidations and cutthroat competition have taken a heavy toll on U.S. airline service. Formal complaints from fliers to the U.S. Department of Transportation are up a steep 27% this year to more than 3,700. Moreover, says Charles Leocha, a Boston travel consultant: "Basically, passengers are at the airlines' mercy." Well, not quite: You can duck problems -- and fight back if need be. Savvy fliers who know which airlines have the best and worst service records (see the table below) can sometimes improve their odds of avoiding travel trouble. Southwest Airline's overall complaint record, for instance, is 10 times better than Continental's. Also, passengers who know their rights can often turn a carrier's foul-up into a personal gain. To help sort out your rights when you fly, we canvassed more than a dozen government regulators, airline industry officials and consumer advocates. Specifically, we asked them for the typical instances of conflict between consumer and carrier, and what -- if any -- remedies a passenger could seek. Below are five frequent snafus, starting with the most common, and what you should do if they happen to you: The airline cancels or delays your flight. Whether because of mechanical problems, inclement weather or bomb threats, an airline can scrub flights at its discretion, and its only obligation is placing you on its next available flight to your destination. However, many carriers will throw in a voucher good for travel on a future flight or will pay for a hotel room if the delay involves an overnight stay -- but often only if you ask for them. This past July, for example, Joan Sullivan, 70, of West Hartford, Conn. was stranded overnight in Washington, D.C. when her United Airlines flight to London was delayed 24 hours because of mechanical difficulties. United made no announcement about passenger accommodations, but those who asked at the check- in counter were given $9 vouchers for dinner, $39 for cabs and up to $99 for hotels. Says Norman Strickman, the chief of consumer affairs at the Department of Transportation (DOT): "You won't get anything you don't ask for." When you ask and the immediate answer is no, stay cool. You may get some compensation -- even a free ticket -- if you later write to the airline's consumer affairs office. Include all flight information in your letter, as well as a description of your problem and what you would like as compensation. You are involuntarily bumped from your flight. When a flight is overbooked, the airline must first seek volunteers willing to relinquish their seats for ones on the next available flight. Generally, the airline will offer cash or a free ticket as compensation. If not, ask the check-in agent for cash or a voucher in exchange for offering to give up your place. Only after all volunteers have been accepted can the line begin bumping ticket holders involuntarily, starting with the last passengers to arrive at the gate. When you're one of these unlucky souls, says Geraldine Frankoski, director of the Aviation Consumer Action Project in Washington, D.C., keep an eye on the clock: If your replacement flight arrives between one and two hours past the scheduled arrival time of the flight from which you were bumped, you're entitled to a check equal to the fare of the oversold flight, up to $200. And if you reach your final destination more than two hours late, the airline must reimburse you twice the fare of your oversold flight, to a maximum of $400. Once again, you can sometimes wrangle a free ticket for your troubles. The airline loses or damages your luggage. The good news is that 98% of all bags reported lost are eventually returned to their owners. Less encouraging is that federal regulations cap the amount you can get back for bags that stay lost at $1,250 per person on domestic flights ($9.07 per pound of luggage on international flights), no matter how many bags perished. If you do lose luggage, notify the airline before you leave the airport and file an official report at the baggage claim office immediately. List everything you packed and what you think it was worth. If your claim seems reasonable, the airline will most likely send you a check (though it may take months). If not, you may need receipts to prove that the designer blouse you reported missing actually cost $200. You lose your tickets. Here's an easy one. Report your lost tickets to the airline immediately. Presuming you can prove you bought the missing ticket, most carriers will issue a replacement for a fee, usually less than $50. You cancel a nonrefundable ticket. Time was when a nonrefundable ticket really was. Today, many airlines will allow you to reuse your ticket at a later date, for a $35 to $50 fee. This past February, for example, James Elkind, 52, of Newton, Mass. bought three nonrefundable round-trip tickets for ( his family on Delta from Boston to Tel Aviv. At the last minute the Elkinds canceled their trip, and, because the tickets were nonrefundable, James contacted the DOT and asked for advice. They suggested that he write to Delta and request vouchers equal to the value of the unused tickets. So he did, and after subsequent correspondence in which Elkind sent along the original tickets, Delta awarded the family three vouchers good for one year and for travel anywhere in the world. Says Elkind: "Delta was very responsive, but I made it very clear what I wanted."

For a complete explanation of your rights and remedies with a particular airline, ask to see the "contract of carriage" at the airlines' city ticket offices or at the airport check-in counter. It spells out check-in rules, delayed flight responsibilities, cancellation policies and more -- all in retina-wrenching detail. Finally, if you believe you've been wronged by an airline or feel its performance has been notably poor, you can voice any gripe by writing to the DOT, Office of Consumer Affairs, Room 10405, I-25, Washington, D.C. 20590. In some instances, they will write to the airline, find out if you've been wronged and help you get whatever you are due.

CHART: NOT AVAILABLE CREDIT: Source: Department of Transportation, Air Travel Consumer Report, January to June 1994. CAPTION: Ranking airline service Complaints to the Department of Transportation rose sharply in the first half of 1994 (see the main text). Below, the major U.S. airlines are ranked by number of gripes received by the DOT per 100,000 fliers. In other columns, the DOT ranks the carriers in three key service areas (1=best; 9=worst).