Airlines exclude valuables and computer equipment from liability and reimbursement if luggage is lost or stolen, and travelers should always carry computers, cameras and jewelry with them onboard rather than checking it in luggage.

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Along with flight delays lost luggage is the most common cause for passenger complaint.

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Similarly, over the next year or two, American will likely see more reservation problems, lost luggage and frequent flier glitches than usual, as passenger information is misplaced during the transition.

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Along with the normal fears of flying, lost luggage, and cancelled flights, with competition significantly reduced, passengers fear that there is a greater likelihood of fare increases.

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Careful study of when and where cancellations are most likely, and adjusting spare aircraft availability to keep flights moving if there is a breakdown helped, as did a rebuilt baggage system at its Atlanta hub to reduce lost luggage.

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