The guideline, which is not binding, means that many existing bags in compliance with airline rules would not be given preferential treatment in the boarding process. The details of how the guideline will be implemented are still murky. It could lead to many fliers being forced to check their favorite carry-on bag.
Fliers may be forced to either buy smaller suitcases or pay a fee to check their bags, which usually costs $25 each way
The recommendation by the International Air Transport Association suggests an "optimal" carry-on size at 21.5 inches tall by 13.5 inches wide by 7.5 inches deep. That is smaller than the current maximum size allowed by most airlines. American Airlines, Delta Air Lines and United Airlines all currently allow bags up to 22 inches by 14 inches by 9 inches - although gate agents don't always enforce those more-generous measurements.
"Once again, the airlines find a way to make their problem the passenger's problem - and an expensive problem at that," said travel industry consultant Henry Harteveldt. The lack of overhead space is due to airlines cramming too many seats on planes and charging passengers to check their suitcases, he said.
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