DENVER — After a man on a Denver-bound United Airlines flight had to be restrained by passengers while the jet returned to Washington Monday night, we decided to take a look at the rising number of reports of unruly passengers on airplanes.

Aristea Brady found that there’s no shortage of video featuring unruly passengers. That’s in her video report above.

In fact, statistics show “air rage” has become a disturbing trend. Experts say you can think of air rage kind of like road rage — it’s rooted in people’s lack of ability to cope with stress.

According to the International Air Transport Association, flight crews reported more than 8,000 bad passenger incidents last year. In 2007 there were only 500 reports.