American's chief executive said Thursday that the cancellations will cost the company tens of millions of dollars, but he says American can withstand the losses.
CEO Gerard Arpey says he takes full responsibility for the airline's failure to comply with a federal safety rule on electrical wiring in its MD-80 aircraft.
American Airlines canceled another 933 flights Thursday after scratching 1,000 flights Wednesday.
It is the latest - and largest - in a wave of cancellations at major U.S. airlines that have caused long lines at ticket counters and made flying even more stressful than usual.
Executives at American said safety was never compromised, and they suggested the nation's biggest airline was the victim of suddenly stepped-up scrutiny by federal regulators.
American estimated that more than 100,000 travelers were booked on Wednesday's 1,094 canceled flights. Many had to scramble to book new flights and were stranded at hotels far from home.
The airline had already scrubbed 460 flights on Tuesday after federal inspectors found problems with wiring work done two weeks ago, during the first set of shutdowns.
The issue stems from an order that the Federal Aviation Administration gave airlines in September 2006 - and gave airlines until last month to meet - about the bundling of wires in the backup power system for the fuel pump of the MD-80 airplanes. The fear is that improperly bundled wires could rub, leading to an electrical short or even fire. However, no serious incidents have been blamed on the bundles, the FAA said.
American officials thought they had fixed the problem last month. But this week, FAA inspectors found problems with the work done on more than a dozen planes. American said it had no choice but to ground all 300 of its MD-80s to deal with the wiring bundles.
American operates about 2,200 daily flights, more than one-third with MD-80s. Nearly half the cancellations were concentrated at two airports, in Dallas and Chicago.
At New York's LaGuardia Airport on Wednesday, hundreds of passengers stood in check-in lines or milled about, using cell phones to get updates on their flights. The airline offered free doughnuts, coffee and orange juice, but there were few takers.
"They should be able to predict these kinds of things," said Laura Goodman, whose flight home to Dallas was canceled. She said would miss an important meeting because the airline couldn't rebook her until Thursday.
New Yorker Michelle Soss had hoped to steal a few days in Albuquerque, N.M.
"I covered my kids' schedules, I covered my work schedule to get away for a few days," she said. "I don't know if I'm getting anywhere."
American's cancellations came after similar delays at Southwest, Delta and United. Last week, hundreds of travelers were marooned when Aloha Airlines and ATA Airlines shut down and filed for bankruptcy protection.
Alaska Airlines said Wednesday it canceled 14 flights to inspect the wiring on its nine MD-80s.
For travelers, the bad news might not end Thursday either. Daniel Garton, American's executive vice president, said cancellations could extend into Friday.
A return to normal operations depends on how quickly mechanics can inspect and fix the wire bundles.
