My time on Delta Airlines 5308, seat 17B, sent my cortisol levels through the roof. Because of “bad weather” and “air traffic,” the departure time got pushed back … and again … and again. As we sat on the JFK tarmac for a solid two hours, a maskless woman directly in front of me didn’t stop coughing. They were sputtering, throaty noises like nothing I have heard before: Less your usual ack and more like huh-khleagggghhh. Since getting vaccinated, I haven’t exactly built my life around avoiding COVID—but still, I’d rather not get sick. And this flight, scheduled for a Wednesday evening in early June, felt more stressful than it had to be.
I did not end up getting COVID, though perhaps I got lucky. Mask wearing is no longer required by major airlines in the U.S., and as anyone who has flown recently can tell you, even in a month of crowded summer travel and the rapid spread of BA.5, Americans are done with masks. “Since the mask mandate ended, I’ve flown to Europe, I’ve flown to New York, I’ve flown to Dallas–Fort Worth, and I’ve flown to a couple more places,” Henry Harteveldt, an airline-industry analyst, told me last month. “Depending on the destination, as little as 20 percent of passengers are wearing masks.”
[Read: Is BA.5 the reinfection wave?]
I get it. Masking up for many hours on a flight is, to use a technical term, a pain. Enduring the discomfort of wearing a mask for the sake of lowering your risk, and everybody else’s, is a tough ask, especially when the risk of getting COVID seems unlikely to abate anytime soon. But what if I told you that there’s a third option here—a way to split the difference between going bare-faced on a plane and never taking off that N95? And that this strategy lets you nearly max out your COVID protection with just a tiny fraction of the annoyance?
Here’s the cheat code: Instead of masking up for your whole flight, just cover up at the start and end of it. Those crucial few minutes—first when you’re boarding the plane, and then after you’ve landed—account for only a sliver of your travel time, but they are by far the riskiest for breathing in viral particles.
Everyone already knows to switch off cellphone service when their flight is about to leave the gate, and then to turn it on the second they’ve landed. Something like the same principle could work for masking, too. Call it “airplane mode” for your face: Keep your mask in place until your plane is in the air, and then put it on again after you land. Otherwise, you’re free to breathe about the cabin.
A commercial flight might seem like the scariest possible setup for super-spreading COVID: Hundreds of strangers who have been God-knows-where over the past few days cram into a metal tube for hours on end. In such quarters, and given current infection rates, you’re very likely to have at least one sick person on board. Indeed, people have caught the virus while on planes, especially on flights without mask mandates. On one trip from London to Hanoi in early March 2020, a sick passenger in business class wound up spreading COVID to 14 travelers and one crew member. But your chances of getting sick don’t stay the same during the course of the flight, Joseph Allen, a Harvard public-health professor who studies ventilation, told me. When the plane is at cruising altitude, the risk will be at its lowest.
That’s because planes are equipped with virus-zapping ventilation systems that put schools, restaurants, and other places to shame. About half of the stale, germ-laden air gets flushed out of the plane as the engines suck in more air from outside, and the other half gets recycled through HEPA filters. No other indoor spot that people typically frequent rivals that level of ventilation: In a home, the air gets refreshed every three hours. In a bank, it’s every 45 minutes. In a hospital operating room, it’s at least every five minutes. On airplanes, that cycle takes as little as two minutes.
But these primo ventilation systems aren’t always on, and they’re not always operating at full blast. To cut down on fuel costs and exhaust emissions—at least before the pandemic—pilots often shut off the ventilation system while planes are at the gate, Dan Freeman, a safety-management systems expert at Boeing, told me. A passenger can sometimes feel that difference in real time: Maybe it’s a bit hot and muggy when you first get on board; then the lights flicker for a second and you hear the engine come to life, followed by a rush of cool air from the AC vent above you. To make matters worse, passengers jam together in the aisles during the hot and muggy phase, huffing and puffing out aerosols as they strain to lift their bags into overhead bins.
Even on the ground, with a plane’s jet engines offline, pilots can use other methods to power ventilation systems. And in the early days of COVID, airlines claimed that they were making the most of them. In July 2020, for example, United vowed to “maximize air flow volume and recirculation of cabin air for passengers from the moment they step onboard.” But it’s not clear whether such measures are here to stay. Representatives for Delta, United, American, and Southwest all told me that, yes, they’re still piping in fresh air while their planes are on the ground. (Spirit did not respond to a request for comment.) Anecdotal evidence is not as promising. In recent months, passengers armed with pocket-size monitors that gauge ventilation have tweeted out images of readings during boarding and disembarking that might indicate the presence of stale air. When a Bloomberg reporter ferried around one of these monitors for several weeks’ worth of travel in April, she found that some of the highest readings of carbon dioxide occurred on airplanes, specifically as she was boarding. (The benefits of HEPA filters would not show up on these monitors.) “It seems wildly variable,” Allen told me. “I don’t think we know what airlines are doing or not doing and why it varies from one plane to the next and one airport to the next.”
So we shouldn’t think about airplane masking as an all-or-nothing binary, where you’re either sucking fabric for eight hours straight or giving up on masking altogether. Covering up for the minutes at the very start and very end of a flight makes a big, big difference. When the plane is stopped, definitely put that mask on; in the air, it’s okay to peel it off. “Wearing your mask during those critical periods is a way to drop the risk of flying,” Allen said, making it “lower than any other part of your trip.”
Let me show you how to put your face in airplane mode. The first step is making sure that you have an N95 or something equivalent. (A baggy cloth mask that’s two years old does not cut it.) Then, keep that mask in place at the very least until your plane leaves the gate. “We’ll get the most bang for our buck with mask wearing if we do it during boarding and deplaning,” Linsey Marr, an environmental engineer at Virginia Tech, told me. You can also choose to wait a little while longer before you take it off, just to make sure that the ventilation system has time to cycle out every bit of standing air. Five to 10 extra minutes should do the trick, Marr said. Or, if you can stand it, keep the mask on until your flight hits cruising altitude. That’s when the plane’s ventilation reaches peak performance, Joshua Santarpia, an aerosol expert at the University of Nebraska Medical Center, told me. He said that when you’re safe to use your laptop, you’re safe to unmask.
Putting your face in airplane mode won’t make sense for everyone. If the guy sitting next to you makes a stray comment about how he can’t smell anything today, even fully active cabin ventilation may not prevent contagion. And if you’re unvaccinated, elderly, or immunocompromised, any number of hours of prolonged masking might be more than worth the inconvenience.
But for Americans who are burned out on endless masking, this approach has the upside of being eminently doable. Let’s crunch the numbers: The average domestic flight distance in the U.S. is 905 miles, and usually takes at least two hours. Boarding and deplaning together take about 50 minutes, on average, Harteveldt said. If you’re masking only then, you’ll be free and clear for more than 70 percent of your trip. Naturally, the math gets even better for international, long-haul flights. On a trip from New York to Singapore, one of the longest commercial flights in the world, you might spend 17 hours—or 93 percent percent of the journey—unmasked, with just a marginal increase to your risk of getting sick.
Ideally, this could be an official airline rule. Maybe Delta gate attendants would hand you a cute Keep Climbing–stamped N95 when they scanned your ticket, and then you’d see a little mask logo above your cabin row, next to the seat-belt sign that dings when turbulence hits. I asked Airlines for America, the industry’s trade group, if it would consider supporting a very limited masking policy of this kind. “We are pleased that the CDC has lifted pandemic-era restrictions—including mask and pre-departure testing requirements—in accordance with science and research,” a spokesperson told me in an email.
For now, airplane mode is a choice, but it’s an easy one to make. The practice will be useful in this summer of BA.5, but also in the future when COVID case rates are much lower. SARS-CoV-2 is not the only airborne virus, of course, and though we don’t go into full lockdown over the flu or common colds, a few basic precautionary measures may still be worth the cost. In 1977, an Alaska Airlines flight sat on the tarmac in Homer, Alaska, for three hours to sort out an engine problem. Within three days, 72 percent of the passengers had come down with the flu. Maybe if people’s faces had been in airplane mode that day in Homer, a super-spreader event would have been avoided. “Do I enjoy wearing a mask in public? Yeah, not even a little bit. But I hate being sick,” Santarpia said. “So if it’s flu season, am I going to wear a mask on the airplane? Yeah, you’re damn right I’m going to.”
