When Irfan Baig checked in for a flight from Memphis to Chicago a full 90 minutes before departure, he had no idea it was going to be such a bumpy flight -- or that he'd never take off.

In addition to having checked in well ahead of flight time, Baig had a confirmed seat assignment and was actually sitting in his seat when an American Airlines employee appeared and chose three passengers to boot off the plane.

"When I inquired why I was picked out of the 100-plus passenger list, I was told I was one of the last to check in," the Seattle-based software engineer recalls. "Really? Ninety minutes ahead?"

Worse still, American gave him a $250 travel voucher, when he was entitled to a cash payment.

Oh, airlines.

But there's some good news about the airlines' policies concerning involuntary denied boarding (IDB to airline geeks, getting bumped to you and me).

First, the compensation for being bumped has gone up.

Passengers can now collect up to $1,300 for being bumped from a domestic flight if they arrive at their destination more than two hours later than scheduled, under Department of Transportation rules revised earlier this year. (The previous maximum was $800.)

Passengers can also get as much as $650 (up from $400) if they get to their destination within one to two hours of the scheduled time, according to the new rule. Different rules apply to international flights: the lower amount is paid for delays from one to four hours, the higher for delays over four hours. And these are maximum amounts: the actual payment will be 200% of the applicable one-way fare for shorter delays, and 400% of the one-way fare for longer delays.

Note, too, that different (and more generous) compensation applies if you're flying within or from the European Union, even if you're not an EU citizen. Read the EU rules.

Second, it rarely happens. The rate of involuntary bumping was 1.09 per 10,000 passengers in 2010, down from 1.23 in the same period of 2009, according to DOT statistics.

But there's bad news, too: It does happen. And when it does, with flights jam-packed thanks to capacity cuts and industry consolidation, there's often not much the airline can do to get you to your meeting or your uncle's funeral on time, or to the cruise ship that's going to sail off to the Amazon without you.

Before you resign yourself to a spot on the airport floor, Airfarewatchdog offers this advice:

Who gets bumped

The process for deciding this is usually based on the last person to check in and/or board, among other factors.

Elite tier members of an airline's frequent flier program are typically less likely to be bumped. You should also know that the folks in the cheap seats have lower priority on some airlines than the ones who paid full fare.

So if you're a very frequent flier at the highest tier of your airline's program and/or paid a full fare (or are a business or first class passenger) you're more likely to get on board than the poor chap who paid next to nothing for his coach ticket. (Interestingly, Baig had no status in American's AAdvantage program when he was unceremoniously ejected from his seat.)

If the airline won't issue you a seat assignment when you buy your ticket, that's a red flag and you might want to choose another flight or carrier.

What you're owed

Passengers should insist on a check instead of a travel voucher (a free round-trip flight, for example), which many airlines typically offer, because vouchers come with restrictions and can be difficult to redeem (you sometimes can only cash them in at the airport).

If your ticket does not show a fare (for example, a frequent-flier award ticket or a ticket issued by a consolidator), your denied boarding compensation is based on the lowest cash, check or credit card payment charged for a ticket in the same class of service (e.g., coach, first class) on that flight.

If you're bumped but arrive at your destination within an hour of the original time, there's no compensation owed. And there are exceptions to the rules that you should read about.

What to do if you're bumped

Most bumpees (whether voluntary or involuntary) have to wait until the original flight is closed out before the agent can assist you.

Often, a seat may open up at the last minute if someone does not board. Also, it's usually only the gate agent at the airport who can handle the booking for the next flight and issue compensation. Calling the airline's toll-free number will not get you anywhere.

If the gate agent instructs you to go to a customer service counter to be rebooked and/or receive compensation, then you can try calling the 1-800 number for assistance, but compensation is almost always issued at the airport by the agent who handled the flight.

If you absolutely, positively have to get there, you could try this: Make your own announcement in the boarding area offering to pay a fellow passenger to give up a seat. Obviously, you need to have a lot of cash in your pocket to make this work, but it's worth a try if you're desperate. You should also ask to be put on another airline's flight, if there is one, to where you were headed.

And rather than just taking your lumps with your bump, you can always ask (nicely) to be flown on another airline to get where you're going, assuming that another airline even flies there and there are seats available. Some airlines (notably, Alaska and United) still have a Rule 240 in their contracts of carriage.

How not to get bumped

One way to avoid getting bumped altogether is to fly JetBlue Airways, because the New York-based carrier refuses to overbook and consequently has the best bumping track record among all major U.S. carriers.

The IDB rankings change quite often, but you can find these and other information on the DOT's Aviation Consumer Protection and Enforcement website.

Also, avoid peak travel days (Tuesday, Wednesday and Saturday are best) and seasons (the day before Thanksgiving and the Christmas holiday periods are notorious for being bump-prone) when planes tend to be jammed full.

Of course, the easiest thing you can do is book way ahead and arrive early. Way early. Don't buy a ticket if there are no assigned seats available. And be loyal: attain some status in your airline's frequent flier program and you're less likely to be ill-treated.

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