Flying has increasingly become a world of the haves and have-nots, starting with purchasing a ticket and continuing as passengers are sorted by status to board.
Once on the plane, passengers can see where they fit in the hierarchy, with the seats getting smaller and thinner and legroom tighter with each passing row. Then, there’s the scramble to secure space in the overhead bins. “By the time you walk down the jet bridge, you are a bundle of nerves,” said Henry Harteveldt, founder of Atmosphere Research Group, a travel analysis firm in San Francisco.
Now, some researchers are arguing that the stresses of flying — and they say income inequality is among them — contribute to an increase in unruly behavior on planes.
Add to that mix the fact that there are fewer flight attendants on duty than there once were. Most domestic flights, said Taylor Garland, a spokeswoman for the Association of Flight Attendants, are run with the minimum number of attendants allowed, which means crews may not be aware of problems.
Airlines fully comply with all federal safety rules and regulations, including those pertaining to crew staffing aboard the aircraft, a spokesman for Airlines for America, the group’s trade association said.
The International Air Transport Association, an industry trade group with about 290 member airlines, found that there was one disruptive incident for every 1,053 flights in 2017, the last year for which data was available. In 2016, there was one incident for every 1,424 flights.
And every incident can affect passenger and flight safety. In some cases, pilots turn planes around, creating major delays.
“Airplanes are the physical embodiment of a status hierarchy,” said Keith Payne, a professor of psychology and neuroscience at the University of North Carolina at Chapel Hill and the author of “The Broken Ladder: How Inequality Affects the Way We Think, Live and Die.” “They are a social ladder made of aluminum and upholstery in which the rungs are represented by rows of boarding groups and seating classes.”
“Crowding,” Mr. Payne added, “is a risk factor for aggression, and more people in a small space make that more likely to happen.”
One general option when an interaction starts to escalate, he noted, is to walk away and cool off. But, he said, on a plane there are few escape routes.
A study, published in 2016, found that multiple classes on an aircraft increased the likelihood of misbehavior. The study, “Physical and Situational Inequality on Airplanes Predicts Air Rage,” by Katherine A. DeCelles, now at the University of Toronto, and Michael I. Norton, at Harvard Business School, was published in the Proceedings of the National Academies of Sciences.
The authors found that the presence of a first-class cabin, in addition to an economy-class cabin, was associated with more frequent air rage incidents. And boarding through the first-class cabin rather than the midsection of a plane increased those incidents.
The air transport association found that disruptive incidents fell into several categories with ignoring safety regulations, excessive drinking before a flight and smoking the most common. The association also had reports of more severe disruptions, including physical aggression and damage to equipment.
It’s far too easy for unruly events to occur, Mr. Harteveldt said.
Now, organizations in Britain and the European Union are starting programs to minimize disruptions. “No one wants to be next to that passenger who has consumed too much alcohol or is aggressive or rude due to other reasons,” Henk Van Klaveren, head of public affairs at the Airport Operators Association in London.
Last July, the Airport Operators Association, the U.K. Travel Retail Forum, along with the air transport association (and later, Airlines UK) introduced a media campaign to curb excessive drinking. Called One Too Many, the program is expected to return this summer.
The campaign began at 10 airports (14 now participate, including Heathrow) with airport screens and posters and a leaflet distributed by the police. It also appeared on Facebook, Instagram and Snapchat.
Bars and restaurants eliminated shots and two-pints from their menus. (A pint in Britain is 20 fluid ounces.) World Duty Free shops, a subsidiary of Dufry, voluntarily introduced sealed bags to carry alcoholic purchases at 24 airports in Britain.
The One Too Many campaign “reminds passengers of their responsibilities and the severe consequences of drinking to excess. These consequences range from being denied boarding to unlimited fines, flight bans and prison sentences for the most serious offenses,” said Karen Dee, chief executive of the Airport Operators Association.
The campaign is showing decreases in alcohol-related offenders at Glasgow Airport, Manchester Airport and Birmingham Airport, according to the operators association.
Beginning in April, the European Union Aviation Safety Agency and the airline transport association started a separate campaign on social media and YouTube. That campaign, called #NotOnMyFlight, is intended to draw attention to rowdy behavior.
The 28 European Union member states and four associate states — Iceland, Norway, Liechtenstein and Switzerland — participate voluntarily. A video, created for dramatic effect, shows a passenger dancing in an aisle, another tossing an inflatable toy and luggage from the overhead bin and a third smoking in a lavatory. Each vignette intersperses a mug shot of the passenger with a designated punishable offense
“The campaign is to remind passengers that each has the responsibility to behave in the correct manner when they fly,” a spokesman for the aviation safety agency said.
One of the more extreme incidents occurred on a Ryanair flight from Dublin to Malta at the end of April. Fights broke out, inebriated passengers danced on seats and abused the flight crew.
The airline crew requested police assistance while in flight and, when the plane landed, the police removed and detained some of the passengers. “We will not tolerate unruly or disruptive behavior at any time, and the safety and comfort our customers, crew and aircraft is our No. 1 priority. This is now a matter for the local police,” the airline said in a statement.
The police in Malta said two 23-year-old male passengers, were arraigned before a magistrate. They were accused of boarding an aircraft when drunk, acting in a manner likely to endanger an aircraft or any person and interfering with the aircraft crew’s ability to perform their duties. Each was fined 1,500 euros, or about $1,674.
In March, two hours into a Hawaiian Airlines flight from Honolulu to Los Angeles, two passengers started quarreling in the aisle. Flight attendants tried to move one to another seat.
The pilot enforced security procedures and returned to Oahu. When the plane landed, the flight attendants were treated for injuries, and the passengers who had been fighting were taken into custody. The aircraft finally arrived in Los Angeles five hours late.
What an airline considers acceptable behavior is outlined in its contract of carriage. This document is available online, at airline ticketing facilities or by request from customer service. Contracts may be different for domestic and international flights.
An international effort is underway to adopt broader regulations to handle passenger disruptiveness, called the Montreal Protocol 2014.
Currently, a serious offense is tried according to the law of the aircraft’s country of registration. The new regulation would consider whether a serious offense had been committed regardless of national registration. Jurisdiction over disruptive passengers would extend beyond the country where the aircraft is registered, to include the destination country. The treaty requires 22 countries for ratification. Currently, 19 have done so.
The agreement adds provisions to recover costs from unruly passengers, said William V. O’Connor, a partner at the law firm Cooley in San Diego whose practice includes aviation matters. “There are issues of proof.” And airlines are reluctant to involve customers as witnesses,” he said.
There is no timetable for the international treaty to go into effect. “You can’t force signatories or put them on the clock,” Mr. O’Connor said.
Yet, “airlines keep crowding people in the same amount of space and keep adding gradations in the space,” Mr. Payne of the University of North Carolina said, even as they create social norms about appropriate flight behavior.