This has been a terrible winter for flying.
Since Christmas, four major winter storms, one after the next, shut down many of the nation’s largest airports for at least a few hours and some for a whole day.
About 86,000 flights from Nov.1 through Feb.11 were canceled at the top 200 airports, according to Flightstats.com, putting this winter on track as one of the most difficult to navigate.
Even so, the severity of the storms was only part of the story this year.
The airlines, stung by highly publicized incidents in previous years of planes stuck on the ground for hours by snowstorms, have changed their policies.
They have become more aggressive in canceling flights beforehand rather than trying to fight their way through the snow.
At the same time, they have made it easier for passengers to cancel or rebook their travel plans, often by waiving fees.
“This winter has been unprecedented in terms of the severity of the storms,” said Rob Maruster, the chief operating officer of JetBlue Airways, which had its own bad experience in February 2007, when dozens of its flights were stranded at the snowbound Kennedy Airport.
“Our philosophy is that if Mother Nature is going to win, let her win, and live to fight another day.” The storms have eaten into the airlines’ bottom lines, adding another worry just as fuel prices have risen.
But so far, halfway through the winter, the impact of the storms is not large enough to threaten the carriers’ newfound profitability.
The industry has been faster to react pre-emptively this year in some measure because of new federal rules that limit how long planes can stay on the tarmac once passengers are on board.
While there is still a debate over whether these rules have increased cancellations, the threat of hefty fines has been a powerful incentive for the airlines not to take any chances.
In December 2010, three domestic flights were held for more than three hours on the tarmac, down from 34 in December 2009, according to the Department of Transportation.
“In the past, the airlines would have made much more efforts to get the airplanes off the ground,” said Robert Herbst, an independent airline analyst who is also a retired commercial pilot.
“I can’t recall the airlines having this amount of continuous weather. With this rule, it is not worth the risk of having an aircraft on the ground. There should be absolutely no disputing that the ruling had some impact,” he said.
Still, as Jeff Masters, the director of meteorology at Weather Underground, a weather Web site, pointed out, “We’ve had an unusual number of high-impact snowstorms that have hit major aviation hubs.”
Kennedy Airport, which had not been shut in a decade, was twice forced to suspend air operations because of two powerful snowstorms in December and in January. Thousands of flights from Atlanta, the world’s biggest airport, were canceled after an ice storm on Jan.9.
Chicago’s O’Hare International Airport and Midway airports, as well as Milwaukee’s airport, all experienced huge delays and cancellations when Chicago was hit by the third-largest blizzard in its history earlier this month.
There is no question that the succession of storms this winter have stressed airports’ ability to cope, experts said. When a major snowstorm hits, the problem is not just plowing the runways. The planes that do get off the ground need to be de-iced beforehand.
Taxiways and service roads must also be cleared to allow planes to reach their gates and bags to be delivered.
When Newark’s airport was hit by a snowstorm last month, Continental Airlines found it easier to fly employees in from Houston for the day because some of the workers based in Newark could not get to the airport.
Adding to the chaos this winter is the fact that airlines have been reducing their capacity and are flying fewer and fuller planes than just a few years ago. Once a flight is canceled, it takes the airline longer to find a seat on another plane.
Furthermore, with the recent mergers in the industry, the airlines are relying on a smaller number of big hubs.
When one airport gets snowed in and is forced to reduce operations, it ripples widely across the country. Many flights out of Los Angeles were canceled, for example, when snow paralyzed Chicago.
“When in doubt, the airlines are now more eager to just cancel,” said Jan Freitag, the vice president at Smith Travel Research. “It is a bit of self-preservation on their part and it’s a little better for passengers who don’t get stranded on the tarmac. They are, however, stranded in the airports.”
Michael McCormick, the executive director of the Global Business Travel Association, said his group was forced to cancel a kickoff event for its new brand in New York because of the snowstorm that blanketed the region on Feb.3.
“The storms kept rolling through,” he said. “It seems we recover from something and then we get hit again.”
On the bright side, airlines have been much more lenient in allowing passengers to change or cancel their tickets. They typically waive the rebooking or cancellation fees, in part to discourage passengers from coming to the airport.
The airlines have also been using social networking sites like Twitter and Facebook to alert their customers to the cancellations.
By canceling flights earlier than in the past, the airlines are effectively calling a “time out” in their operations, which allows them to resume flying more smoothly when the bad weather has passed.
This reduces the risk of having their planes stranded at one airport and their crews stuck at another. It also means they are less likely to cancel a flight at the last minute, while passengers are waiting at the gate.
“Airlines have become smarter,” said Mr.Maruster of JetBlue.
Still, that has not eliminated travel nightmares this winter.
Marilyn Horan, a retired assistant school principal from Brooklyn, said she was stuck for 30 hours at Kennedy Airport after a blizzard blanketed much of the Northeast with snow the day after Christmas.
She and her husband were scheduled to fly to Vienna on Austrian Airlines. They eventually made it out the following night. “It’s the last time I take a plane in the winter,” she said.
Another traveler, Johanna Greeson, ended up driving about 500 miles from Cincinnati to her home in Durham, N.C., after her Delta Air Lines flight was canceled because of a snowstorm in late December.
“It was faster than waiting for the airlines to sort themselves out,” she said.
Mr.Herbst estimated that the storms would shave $100 million in earnings for the airlines, which remains a manageable amount, given that the flights canceled accounted for about 4 percent of all scheduled flights.
Delta Air Lines said the storms would reduce its revenue by $75 million in the fourth quarter of 2010 and the first quarter of this year.
During a four-day period, Jan.9 to 13, when its hub in Atlanta was crippled by an ice storm, Delta said it canceled 5,550 flights.
Another storm in early February led to another 2,950 cancellations over a three-day period.
One sector has benefited from the chaos, however.
The room occupancy of airport hotels was 5 percent higher last December than in December 2009, as stranded travelers sought them out, said Mr.Freitag, whose company specializes in benchmarking hotel performance.