NEW YORK (AP) -- You've heard the horror stories of airline passengers stranded on the tarmac for hours without food or water or even sanitary bathroom conditions. Or worse, you've lived the experience. You wondered, why is this allowed to happen?
After years of sparring between passenger advocates and defiant airlines, the government has stepped in. Starting Thursday, U.S. airlines will have to let passengers off the plane after three hours or face potentially huge fines.
But depending on the airport you're at and the decisions made by pilots, passengers will have different experiences with the rule.
Here are some questions and answers related to the rule.
Question: Why pick three hours as the deadline?
Answer The Transportation Department modeled the 3-hour cutoff on legislation that is still under consideration by Congress. Passenger advocates -- led by Kate Hanni, who endured her own flight delay ordeal in 2006 -- originally pushed for a two-hour limit. Three hours was a compromise.
Q: When does the clock start ticking?
A: Once the cabin doors close. If a plane sits at the gate with the doors open, that time doesn't count -- whether it's five minutes or five hours.
Q: What happens when the 3-hour mark is approaching and we're still on the tarmac?
A: The pilot can opt to turn the plane around. But he'd better do so pronto because the countdown stops when the passengers are free to get off. US Airways has told pilots to turn back after 2.5 hours unless takeoff is imminent. Continental has less patience. Its pilots will turn around at the 2-hour mark.
Passengers can disembark at the gate or the airline could allow them to get off on the tarmac by using staircases or buses to shuttle them back to the terminal.
The pilot could decide to wait it out. But if a plane doesn't take off before three hours, the airline faces a fine from the Transportation Department of up to $27,500 per passenger. That's a lot of peanuts. Or bags of blue potato chips.
There is one condition where sitting beyond three hours is allowed. It's when the pilot decides (with the help of air traffic control) that it's not safe to move.
International airlines are not subject to the 3-hour delay rule, even if they land or takeoff from U.S. airports.
Q: Are the airlines required to do anything for us if we're stranded on the tarmac?
A: Airlines have to provide passengers with enough food and water.That means a snack pack of pretzels or other munchies and a bottle of water. They also have to keep bathrooms in working condition and have certain medical supplies available.
Q: Can the airline cancel a flight to avoid violating the rule?
A: Absolutely. A number have threatened to do so.
Q: What are my options if that happens?
A: If the cause is within the airline's control, you're better off than if the flight is canceled because of weather. If there's a snow storm or tornado coming, the airlines won't promise much.
But if the trouble is the airline's fault, most will rebook you on a flight -- even on a different airline -- within four hours of the original flight, if they can. Planes are expected to be full this summer, so empty seats might be a rarity.
Q: How likely is it that I'll be stuck for 3 hours?
A: The government said there were 903 delays of 3 hours or more last year -- but that's out of more than 6.4 million flights -- one for every 7,143.
In other words, while you're more likely to have a lengthy delay than sink a hole in one in golf (1 in 12,000, according to Golf Digest) it's still pretty rare. But 4,717 flights were delayed between two and three hours last year. A number of those will likely be canceled once the rule goes into effect.
Q: What part of the country can this rule impact passengers most?
A: There is more potential for delays in big cities like New York, Chicago and Atlanta. But if airlines start canceling flights, passengers all over the country could feel the consequences. If a flight from New York to Atlanta is canceled, for example, the crew wouldn't be available for a later flight to, say, Birmingham, Ala.
Q: Who keeps track of airlines that violate the 3-hour limit?
A: The Department of Transportation collects the data. U.S. airlines will be required to post delay data on their websites by the end of July.
Q: What can I do if I feel like the airline didn't hold up its end of the bargain when I was delayed?
A: You can complain to the airline, or take your complaint to a higher authority by filing a grievance with the Transportation Department. You can even complain via the airline's Facebook page or Twitter account. The airlines are required to respond to all written complaints -- and that includes the Internet.
Q: What started all this?
A: As legislation was being considered in Congress, a real-world example spurred action: A Continental Express jet full of passengers was stuck overnight in Rochester, Minn. last August -- just yards from the terminal -- because no one would let the plane pull up to the gate. That incident prompted the Transportation Department to draw up the new rules, which were approved in December.
Airlines reporter David Koenig in Dallas contributed to this story.
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