Sour Summer Vacation

June 29, 2007 — -- Those who are traveling for the Fourth of July holiday are bracing themselves for what could be a nightmare experience at the airports and in the skies. The American Automobile Association estimated that about 4.7 million people, 11 percent of holiday travelers, will fly over the Fourth -- that's up 3.5 percent from a year ago.

They're facing an aviation system that many believe is on the verge of collapse.

It's already been a long, hot summer for travelers. According to FlightStats.com, for the first 15 days of June, the number of canceled flights was up 91 percent from the same time a year ago.