Anyone who has flown on a commercial airline this year knows that it's getting awfully crowded up there. Major carriers are reducing flights and flying with smaller planes while increasing the number of passengers they can squeeze onto each flight.

Anyone who has flown on a commercial airline this year knows that it's getting awfully crowded up there. Major carriers are reducing flights and flying with smaller planes while increasing the number of passengers they can squeeze onto each flight.

There are a number of ways that this trend makes the flying experience more unpleasant, not the least of which is an unhappy phenomenon known as involuntary bumping.

Airlines often oversell tickets for flights to make up for the inevitable no-shows, so the number of people waiting to board a plane many times exceeds the number of seats waiting in the plane.

Airlines turn to voluntary bumping first, offering volunteers a travel voucher or other incentive to wait for a later flight.

But as it becomes harder to book flights on the same day, travelers are becoming increasingly averse to voluntarily giving up their seats. When there aren't enough volunteers, the airlines then force a certain number of people to wait for another plane.

The Rocky Mountain News in Denver, citing U.S. Department of Transportation statistics, recently reported that nearly 37,700 passengers were involuntarily denied boarding this year through June, a 13 percent increase from the same time last year. That puts the amount of involuntary bumping on track for record levels this year.

Bob Weiss, editor of the Boston Airport Journal, says the only effective way to avoid being bumped is to arrive at the gate at least 30 minutes early, because many airlines will bump the passengers who were the last to arrive.

''If you do not (get there early), the chances of getting on a plane later in the day are very difficult,'' Weiss says. ''All the planes are almost booked.''

The federal government mandates that travelers who are bumped involuntarily be paid up to $400, depending on the length of delay and the cost of the ticket. SmarterTravel.com, a Charlestown-based consumer Web site, said JetBlue is the only major carrier to go beyond the federal requirement, offering $1,000 to displaced passengers.

SmarterTravel.com also reported that the DOT is considering an increase in the compensation requirement, partly because of the rise in involuntary bumping this year. If you've got an opinion, you can check out the DOT's docket Web site to register it.

The Patriot Ledger

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