But could you be grounded for days instead?
Starting April 29, passengers will have the right to get off a plane if it's stuck on a tarmac for three hours unless doing so would jeopardize safety.
Two airlines - Continental and US Airways - are already telling pilots to return planes to the gate in time to beat the deadline. Airline officials say hundreds of flights are likely to be canceled at the hint of bad weather as carriers try to avoid potential fines in the millions of dollars for violating the 3-hour rule. With planes expected to be full this summer, bumped travelers will have difficulty finding an empty seat on a later flight.
"The misery index for airline passengers is definitely going to go up," says David Stempler, an aviation lawyer and president of the Air Travelers Association.
Some industry experts say cancellations aren't likely to be as severe as many fear. They argue that financially strapped carriers won't risk losing revenue and passenger loyalty at a time they desperately need both. Government officials say they rarely impose the maximum penalties.
Travelers won't know who's right until the first big summer thunderstorm paralyzes a major hub, such as New York, Chicago or Dallas. Weather is the biggest cause of long tarmac delays.
W. Keith Jones, vice president of sales for a Dallas-area software company, says airlines should be able to adjust schedules when bad weather hits. While waiting for a recent flight to Hartford at Dallas-Fort Worth International Airport, Jones vowed to retaliate if his flight is scrubbed after two hours on the tarmac.
"They do that and they start giving me reason to pick another airline," says Jones, who believes some airlines such as Southwest handle disruptions better than others.
Scott Ivey, a frequent flier and owner of a technology-services company, says he sat on grounded planes at least three times in recent years, the longest a six-hour wait on a Southwest jet in Columbus, Ohio, due to fog. He agrees with allowing passengers to disembark.
After a couple of hours in close quarters, "tempers can flare," he says.
But Jill Peloquin of Sacramento, Calif., doesn't want her plane turning around if there's a chance of taking off.
"If they have air conditioning, I would go with sitting on the tarmac," Peloquin says. She fears pilots won't find a gate available for discharging passengers. And she's afraid later flights will be full.
Airlines usually don't pay hotel and meal tabs for passengers stranded by bad weather or other factors outside their control, the past week's mass cancellations from a volcanic ash cloud over Europe being a prime example. If airlines cancel flights to avoid violating the 3-hour rule they won't pay for customers' hotels, says Meara McLaughlin of FlightStats, which tracks on-time performance in the airline industry.
Delays longer than three hours are rare. In 2009, the government counted 903 out of more than 6.4 million flights - one for every 7,143.
If the new rules had been in effect, the airlines would likely have canceled all 903 flights before three hours. And maybe many more.
"There is a large number of flights that are delayed between two and three hours where we'll have to make a hard-deadline decision" whether to cancel, says Steve Hozdulick, an operations executive at Southwest Airlines.
Southwest had 33 flights delayed three hours or longer last year, one of the lowest rates in the industry. But Hozdulick estimates that another 200 to 300 were stuck on the tarmac at least two hours, and those would now be prime candidates for cancellation.
The new rules don't take effect for more than a week, but US Airways is already telling pilots to return to the gate after two and a half hours unless take off is imminent. It says one plane returned to the gate in Atlanta on April 8 after a long weather delay. Continental Airlines has set a cutoff of two hours but said as of early this week that no planes had returned to the gate.
The airlines say they have a powerful financial incentive to cancel flights early. The maximum penalty for violating the new rules - or any airline-consumer regulation for that matter - is $27,500 per passenger per day. For a fully loaded medium-sized jetliner such as a Boeing 737, that adds up to more than $3.5 million.
According to Transportation Department records, the largest civil penalties for consumer-rule violation over the past two years were $375,000, imposed in separate cases against Delta and Spirit Airlines. Most fines were much smaller, and in most cases, the department waives half the fine if airlines don't break the rules again within a year.
Besides the 3-hour limit, the new rules require the airlines to provide food, water, lavatories and emergency medical attention to passengers after two hours on the plane. They also grant travelers more information on delays before buying a ticket.
The airlines had been able to fend off rules like these until last August, when a Continental Express jet full of passengers was moored overnight in Rochester, Minn., just yards from the terminal because no one would let the plane dock at the gate. The 6-hour Rochester standoff prompted the Transportation Department to draw up the new rules, which were approved in December.
Passenger advocates and the government say the airlines should spread flights out during the days instead of bunching them in peak morning and late-afternoon hours. In the worst on-time month last year, June, delays in the morning typically cascaded through the day, usually peaking between 5 p.m. and 8 p.m., prime time for thunderstorms.
The Transportation Department says carriers also can do a better job having extra planes and crews, but that would raise airlines' costs.
The carriers point the finger back at the Transportation Department, saying an antiquated air traffic control system causes most of the delays.
Even with the new rules imminent, the industry has not stopped fighting.
An industry trade group, the Air Transport Association, has asked the Transportation Department to postpone a requirement that carriers post statistics about late flights on their Web sites. And several carriers have asked the department to ignore long tarmac delays in New York - the nation's most congested airspace - until this fall because of runway construction at John F. Kennedy International Airport.
One of carriers seeking to postpone penalties in New York is American Airlines, which at the same time is adding flights at JFK. "We don't think it's going to be a big deal," American CEO Gerard Arpey confided last week when asked about the runway work.
So why ask for the exemption from the 3-hour limit?
"To prepare," he said, "for unforeseen circumstances."