Aviation security expert Jeffrey Price told Business Insider that the "stress of air travel," grueling flight delays "where passengers aren't being consistently informed about what's happening," not having enough leg room in airplane seats, travelers reclining their seats all the way back, and "in some cases, arbitrary rules invented by crew members" can all "contribute to the problem."

"Increased stress pretty much always results in a shorter fuse, whether that's on a plane or on the road," said Price, an aviation professor at Colorado's Metropolitan State University of Denver.

There have been hundreds of incidents this year

In 2021, the US Federal Aviation Administration FAA implemented a "zero-tolerance" policy against unruly passengers after reports of misconduct by travelers jumped.

This year, the FAA has recorded more than 1,900 "unruly passenger" reports.

While that's significantly down from the record-high of nearly 6,000 reports in 2021, agency data shows there are still more incidents compared to the years before the COVID-19 pandemic.

According to the latest available FAA data, 39 of the most serious of this year's cases — which included reports of physical assault against both passengers and crew members — were referred by the FAA to the FBI for criminal investigation as of August.

Globally, cases of unruly plane passenger incidents have skyrocketed from 2021 to 2022, with one unruly flier incident reported for every 568 flights in 2022, up from one per 835 flights in 2021, according to data released this year by the International Air Transport Association.

The IATA, which does not yet have 2023 data for unruly passenger reports, found that the most common incidents for 2022 involved non-compliance with flight crew such as the smoking of cigarettes, e-cigarettes and vapes in the plane cabin or bathrooms, verbal abuse, and intoxication.

Incidents of physical abuse remain rare, but showed an "alarming increase" of 61% from 2021 to 2022, occurring once every 17,200 flights, the IATA found.

'Post-pandemic behavior is different'

IATA spokesperson Perry Flint told Business Insider that it's "clear that post-pandemic behavior is different to that which took place before."

Price echoed those remarks, saying that he believes, overall, that there's been a "social change" that has taken place post-pandemic with people seemingly acting "more entitled" and "less polite."

"When traveling by airline there is so much that's out of the control of the passenger," noted Price, explaining that the "lack of control amplifies the stress even more."

"In no case, however," he said, "does anyone deserve to be physically assaulted."

Meanwhile, a study published this year in the peer-reviewed academic journal Deviant Behavior found that unruly behavior by plane passengers was largely fueled by alcohol consumption.

Researchers from the University of Texas at Dallas looked at data from more than 915 incidents reported to the Aviation Safety Reporting System over 21 years between 1999 to 2020.

"In a number of instances that we reviewed, people were already intoxicated as they were boarding the aircraft," said one of the study's authors, Sheryl Skaggs, a sociology professor.

Passenger misconduct is the 'new normal'

Vance Hilderman, an aviation expert and CEO of aviation consulting firm AFuzion, told Business Insider that bad behavior by airline passengers is "unfortunately" the "new normal."

It's also exacerbated by social media and copycats, he said.

"Unruly passengers are called out more often and fellow passengers record, report [it] far more often," Hilderman said.

Flight delays, he added, "begets more frustrated passengers" in the skies.