Not long ago, the challenge of carrying bags onto airplanes pertained to size. Would you be able to stuff that teeming roll-aboard into the overhead bin? It took a deft touch and several grunts, but at least the bag was within arm’s reach.

Now the challenge is getting a bag on board. Since airlines began charging for checked baggage, more carry-ons have been frozen out. Being forced to check bags at the gate has become common; I counted 15 on a recent flight. During preboarding announcements, airlines have taken to telling fliers that the last people on board essentially have no chance of their bags accompanying them in the cabin.

Business travellers, often in a hurry and on the road for a short enough time that carrying baggage on is a must, have learned the drill particularly well.

Will this battle for overhead space resolve itself anytime soon? Well, sort of.

Gary Chris, a spokesman for Heath Tecna Inc., a Bellingham, Wash., firm that designs and builds aircraft interiors, said his company has had steady orders during the last 18 months to expand overhead bins on existing aircraft (replacing the bins outright is too labour- and cost-intensive for many airlines; an expansion takes a mere 12 hours). The company hasn’t had this many orders since about 10 years ago, when roll-aboard suitcases became both larger and the rage, Chris said.

The benefit of expanded overhead space is twofold: Passengers are happier, and airlines are delayed less by checking bags at the gate.

Manufacturers Boeing and Airbus plan to add planes to their fleets with deeper overhead interiors, but those are "three or four years" away, Chris said. He described the future of airplane interiors as "more spacious, with maximum storage space." Whereas today’s bins are fixed with swinging doors, future bins are likely to be built more deeply into an airplane’s ceiling and sides and will swing down into the cabin when open. When closed, they’ll be almost recessed, he said.

"There will be more space and more light in the cabin," Chris said.

And yes, much of it can be traced to airlines’ decisions to charge for checked baggage, he said.

In the short term, John Pincavage, an airline industry consultant, said that the battle for overhead space will continue to be a win-lose proposition, with plenty of travellers losing. He guessed that rather than explicitly charge for carry-on bags as Spirit Airlines started doing last year (as much as $45 per bag), airlines will charge in even more backhanded ways.

For instance, boarding earlier - a guarantee of access to overhead bins - will become more common as an extra charge. Eventually, however, he figures that charging for carry-ons will become more common.

"It’s all about incremental revenue," he said. "It will be a question of which fee you want to pay."

And will it be more expensive to carry or check? That’s a tough call, he said. Airlines will study whether it behooves them to have the bags up top or in the plane’s belly - financially speaking, of course - and price accordingly.

WHAT AIRLINES ALLOW

Want to know the luggage carry-on restrictions before you get to the airport if you are travelling in the U.S.? A handy list of tips and specs can be found at this website: luggageonline.com/about_airlines.cfm.