Was 2014 the year of the bad airline passenger?

Airplane seats. (Fotolia)

Airplane seats. (Fotolia)

Nicole Ireland, QMI Agency

, Last Updated: 12:11 PM ET

Judging by the headlines, 2014 saw more than its fair share of emergency landings in Canada and the U.S. A disturbing trend? Maybe — but not because it shows a rise in mechanical issues or terrorist threats. The reason hundreds of passengers had their trips abruptly interrupted was due to the bad behaviour of their fellow passengers.

Last summer, a Sunwing flight headed from Toronto to Panama had to turn around over U.S. airspace when a 25-year-old man from Mississauga, Ont., allegedly threatened the plane.

An F-16 fighter jet escort later, he was facing charges of mischief and uttering threats. His parents have said their son suffers from mental illness.

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About a month later, another Sunwing flight — this one going to Cuba — also got a military escort back to Canada when two young women allegedly got drunk, smoked in the airplane bathroom and got into a fight.

Apart from cases of mental illness or drunkenness, there's a much broader set of issues at play, according to Dr. Jane Storrie, president of the Ontario Psychological Association.

"It's very similar to what we're seeing in road rage," Storrie said. "(It's) an increase in these instance(s) where people are acting out."

Like road rage, it's rooted in people's lack of ability to cope with stress, for reasons ranging from fatigue to never unplugging from mobile phones and social media.

Add that to a more stressful flying experience than in the past — such as post-9/11 security lineups and baggage fees — and people's nerves could be shot before they even board the plane, the psychologist said.

"By the time we've taken our seats, we've coped with traffic congestion, parking, lineups, making our way through crowds of people and suitcases, all the while we're afraid of being late and dealing with a noisy, overstimulating environment and still dealing with calls or texts from the office," said Storrie.

When a passenger loses it, it's often triggered by "one last straw," she said.

For two men, that last straw appears to have been fellow passengers reclining their seats.

Last August, a United Airlines flight had to make an emergency landing when a man used a small device known as a "knee defender" to block the woman in front of him from reclining her seat. He refused to remove it and she threw a glass of water on him, according to reports.

Later that same week, a reclined seat reportedly set off another scuffle on an American Airlines flight, resulting in a 60-year-old man allegedly grabbing the flight attendant who was trying to calm him down.

None of this surprises Storrie. In fact, she suggests the reduction in legroom and seat width to squeeze in more passengers could contribute to air rage.

"Studies show that crowding in and of itself leads to alienation and a breakdown of our ability to ... control our behaviour and emotions," she said.

Storrie said people need better ways of coping with modern stresses -- a remedy that extends far beyond airplanes and cars.

"There may not be easy answers to this."