Lost baggage is actually a worse problem than reflected in the big airlines' statistics. Regional airlines misplace bags at a higher rate. But they report their statistics separately, even though many passengers travel on these regional airlines for just one leg of their trip.
Counting together American and the regional airline it owns, American Eagle, mishandled bags grow to 8.69 per 1,000, or a total of 639,146 through Sept. 30.
American Eagle had the worst bag-handling record of 20 airlines tracked by the Bureau of Transportation Statistics during that period, the agency reported.
American's baggage operation at O'Hare, the airline's second largest hub, is massive, with more than seven miles, or 11 kilometers, of conveyers, hundreds of workers and scores of tractors pulling baggage carts.
Checked bags are immediately sent on a fast conveyer to be screened by the Transportation Security Administration and then sent back to American's big bag room. There, bar-code readers direct the bags onto piers that handle one or more destinations. From there, bags are placed on carts and towed out to planes for loading.
Bags with unreadable tags are left to circle the piers up to three times before being hauled off and manually placed in the correct stack.
About 2 percent are misread and dropped onto the wrong pier. Then, it is up to a worker stacking the bags on carts to notice the mistake.
American and other domestic airlines have resisted investing in radio frequency identification tags, which are used by big retailers to track inventory and are far more accurate.
The tags cost about 20 cents each so it would cost $50,000 a day for American's 250,000 bags, plus the cost of hardware to read them at each step in the process.
''We don't lose enough bags to justify that investment,'' said Mark Mitchell, American's managing director of customer experience.
American's workers also stopped unloading entire planes in some instances in the last year, instead hauling off only bags that need to be rushed to connecting flights and then returning for the rest, said Wilewski, the baggage manager. Bags failing to make connections account for 60 percent of mishandled bags, American said.
In the months ahead, American also plans to install laptop computers on tractors that pull baggage carts so that workers know of last-minute gate changes, late arrivals and other complications. Drivers have long used written orders and often arrived at a gate to find the expected plane was not there.
American handles 20,000 to 35,000 checked bags a day in Chicago. Wilewski's goal for November is 7.95 mishandled bags for every 1,000. ''We're not to go above that,'' she said. ''We're under it right now.''
Her Chicago operation met its monthly goal for the first time in two years in May and then met it again in September and October.
So, last Thursday, when morning flights to London and Honolulu were both delayed by more than eight hours because of mechanical problems, her staff quickly rounded up bags that had already been checked, knowing some passengers would switch flights or perhaps cancel their trip altogether.
As some passengers were rebooked, workers tried to keep their bags with them.
Wilewski said they got nearly all the London bags on the correct flights, but ''we did miss maybe 15 bags on Hawaii'' in the confusion.
The company says it's far different than it was a year ago, when a different group of executives was consumed with fighting for the airline's existence.
Knowing few things irritate passengers more than having their bags misplaced, many airlines insist they are working to improve their delivery.
In the third quarter 2006, four of the six airlines with the worst on-time records were regionals.
About 90 percent of Charlotte's travelers will fly US Airways, an airline that last holiday season delayed or stranded 560,000 passengers.