Airlines are fretting over how to fix a problem they created.

Since checked baggage fees have become common among U.S. carriers, the battle over overhead bin space in airplane cabins has become intense. Every boarding announcement is accompanied by a crowd of eager travelers, desperate to get their bags in the spaces above their heads.

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On Tuesday, the International Air Transport Association (IATA) announced a new initiative "to optimize the accommodation of carry-on bags given differing carry-on bag sizes and airline policies."

IATA says it is solving the problem of carry-on bag sizes on behalf of passengers.

“The development of an agreed optimal cabin bag size will bring common sense and order to the problem of differing sizes for carry-on bags,” said Tom Windmuller, IATA’s Senior Vice President for Airport, Passenger, Cargo and Security. "We know the current situation can be frustrating for passengers. This work will help to iron out inconsistencies and lead to an improved passenger experience."

The new suggested carry-on size, at 21.5 x 13.5 x 7.5 inches, "means that theoretically everyone should have a chance to store their carry-on bags on board aircraft of 120 seats or larger," according to IATA.

Current carry-on baggage allowances average 22 x 14 x 9 inches.

There's at least one problem with IATA's baggage recommendations: Shrinking the baggage size allowance means that trusty carry-on you've learned to pack a week's worth of clothing into may soon be too big.

But a new luggage purchase is exciting, right? (Hint: No.)

It's also worth considering why everyone is trying to carry on their baggage, which is often an effort to save the $25 or $50 in checked bag fees.

"Once again, the airlines find a way to make their problem the passenger's problem — and an expensive problem at that," travel industry consultant Henry Harteveldt told the Associated Press.

However, IATA has framed the problem as an issue of convenience.

“What we’re trying to do is take away that uncertainty from the 120th passenger in line -– will I be able to bring my bag into the cabin?” Perry Flint, an IATA spokesman, told the Washington Post.

IATA is emphasizing that the suggestions are not set in stone, and that each carrier sets its own standards. However, an excuse to shrink baggage allowances — and potentially force travelers to pay to check their bag — is likely appealing to airlines. In 2014, U.S. airlines alone collected $3.5 billion in baggage fees.

Last year, many travelers were surprised to find their carry-on bags had suddenly become too big after major airlines reduced the maximum size allowances. It's safe to expect a repeat.

"A number of major international airlines have signaled their interest to join the initiative and will soon be introducing the guidelines into their operations," IATA announced in the statement.

Baggage in the new "optimum size" could be available in retail stores before the end of the year, according to IATA.