Every year around this time of year, airports are jammed with travellers heading all over the world. It begs the question: If this happens so regularly and reliably, why don't airlines just add more flights around this time of year to keep up with the demand?
As CNBC's Phil LeBeau discovered, it's not as easy as just renting a few extra planes when there's an abundance of passengers ready to travel:
Despite mergers in recent years and the retiring of older, less-efficient planes, carriers have nowhere to turn... That's not how the commercial airline business was set up to operate, industry experts said.
"It's not realistic to think airlines could add planes for a few days," said Josh Marks, CEO of airline consulting firm masFlight. "The airlines would love to have the flexibility to add capacity, but the system is not set up for it."
There are also government regulations that limit how many flights can take off and land at an airport on a given day -- and they're already maxed out. Not to mention the airlines would need to somehow find extra pilots and flight crews to staff those additional flights. So basically those long airport lines at Christmas and other holidays aren't going away anytime soon. [NBC News]