

Unruly passengers on planes worldwide increased 14 percent in 2015 over the previous year, according to the International Air Transport Association. (iStock)

On New Year’s Day, a kerfuffle on an international flight led a San Francisco-bound United Airlines plane departing from Sydney to divert to Auckland, New Zealand. On what would have been a 13-hour flight, an agitated middle-seat passenger — who was recorded on video — exchanged terse words with a flight attendant and was subsequently arrested when the plane made an early landing. The encounter was the latest incident of air rage — something that flight attendants say is on the rise.

“The conditions on board just lead to more potential for air rage,” says Sara Nelson, international president of the Association of Flight Attendants-CWA. Nelson ticks off the reasons: tight seating, fuller flights, alcohol consumption, fewer flight attendants, human nature.

“Any time you get a whole bunch of humanity packed in together there’s opportunity for a conflict,” Nelson says.

[A man got a middle seat on a 13-hour flight. Passengers recorded his ‘fit of rage,’ then arrest.]

According to data from the International Air Transport Association, a trade association that represents 265 airlines and 83 percent of global air traffic, unruly passengers on planes worldwide increased 14 percent in 2015 over the previous year. In 2015, there were 10,854 reported cases of such incidents, or one in every 1,205 flights. In 2014, there were 9,316 incidents, or one per 1,282 flights. Alcohol or drug intoxication was reported in 23 percent of the cases; physical aggression was reported 11 percent of the time. Verbal abuse and failure to follow the instructions of the flight crew were cited in a majority of the incidents.

(Facebook.com/NeilK)

A recent study published in the Proceedings of the National Academy of Sciences of the United States found that airplane design may play a role in air rage. The study, authored by Katherine DeCelles, who is the James M. Collins senior lecturer and a visiting associate professor of business administration at Harvard Business School, and Michael Norton, the Harold M. Brierley professor of business administration at the same institution, found the mere presence of a first-class section in a plane mattered: The chance of an air rage incident happening in economy is 3.84 times greater when there is a first-class section.

[An unruly couple forced their flight to turn back. Police boarded, and passengers cheered.]

“Making class difference more salient can be bad for everyone,” DeCelles says.

For the study, the researchers had access to a database containing about five years of air-rage incidents from a major airline. (DeCelles declined to say which airline, citing a nondisclosure agreement.) For every 1,000 flights, there were 1.58 incidences of air rage in economy and .31 in first class.

The researchers found that when passengers enter the plane through the front and pass through a first-class section, rather than entering in the middle of the plane and into their own designated section, the odds of air rage increase, both in economy and in first class: Economy passengers are 2.18 times more likely to become unruly and first-class passengers are 11.86 times more likely to act out than when they board from the middle. DeCelles points out that these results statistically account for a number of other factors that might relate to first class and boarding patterns, such as leg room, flight size and flight length.

In describing the emotions of the passengers in the reports, flight crews classified disruptive first-class passengers more frequently as “belligerent,” and described economy upsets as “emotional outbursts.” (Beyond the report, the researchers didn’t have any additional information on the passengers’ actual emotions or other factors, such as alcohol intake, says DeCelles.) Based on the correlational results, DeCelles theorizes that first-class passengers may have felt a sense of entitlement, which led to their reactions, while those in economy may have felt a sense of deprivation and frustration.

[They aren’t just for backpackers. ‘Poshtels’ boast chic decor and the chance to be social.]

(Erin Patrick O'Connor,Julio Negron/The Washington Post)

“We all know we live in a class-based society, but it’s never quite so in your face as when you board an airplane,” DeCelles says.

Whatever the cause, Nelson, who is also a flight attendant with United Airlines, says that employees are trained to handle passenger interruptions of all types, and they are also presented with the option of taking a self-defense class offered by the Transportation Security Administration. She adds that the Federal Aviation Administration takes poor passenger behavior seriously: Passengers who interfere with the duties of the flight crew could face criminal charges or be fined up to $25,000 by the FAA.

Any type of unexpected behavior in-flight could be cause for concern, Nelson says. Flight attendants are taught that if someone is acting out, it may be a distraction for a larger threat.

“We are in a metal tube hurtling through this space, an object that has been used as a weapon of mass destruction,” says Nelson. “That is the new world.”

Silver is a freelance writer and author of “Frommer’s EasyGuide to Chicago.”

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