Jim Urquhart / Reuters

Modern air travel has become so grueling that it is easy to lose sight of its greatest, near-miraculous achievement: Commercial airline travel is astonishingly safe—yes, even given the two horrific 737 Max crashes over the past 18 months, and even considering the primitive-terror factor that makes the prospect of death in the sky so much more frightening than most other fates.

In a recent period of more than nine years, there were no crash-related deaths aboard U.S. airliners. (That period ran from February 2009, when a Colgan commuter plane crashed in icing conditions, on approach to Buffalo, until April 2018, when debris from an engine explosion on a Southwest flight destroyed a window, killing the passenger sitting nearby.)

Fifty people were killed in that first accident; one person in the second. But in between those tragedies, every single U.S. airline flight took off and landed without killing anyone aboard. That was a total of well over 50 million flights (the U.S. airlines operate between 5 and 10 million flights per year), carrying more than 5 billion passengers. Not all of those 5 billion literally walked off the planes: Some were in wheelchairs, others had suffered in-flight medical emergencies or even died. But during a period when roughly 100 Americans were dying each day in car crashes, and another 100 from guns, absolutely no one was killed in a U.S. airline accident.

How can this be? It turns out that the very factor that makes modern air travel so unpleasant for all but the superpremium customers explains—in reverse—what has made it so safe.

The grinding unpleasantness of the modern airline experience comes from its ruthless, lean efficiency. Every bit of slack has been carved out of the system. Does a member of the flight crew show up late, or cancel at the last minute because of sickness? There’s not a spare crew member waiting to fill in. Is a plane missing a part that’s on the pre-takeoff checklist? There’s no spare part, or spare plane, to be swapped as a substitute. Has fog or a thunderstorm canceled your flight? Too bad—the next available flight is not till tomorrow, because all the rest today are fully booked. And so on. These Gradgrind-style efficiencies have made the airline industry profitable (as has its consolidating into a few dominant carriers), and they’ve transferred the inconvenience of the unexpected onto its customers.

That’s the part of air travel passengers see. What they don’t see is the safety system that—even now—operates on the opposite of the leanest-possible-resources model.

For instance: You probably can’t see this from seat 23D on United or Delta, but every commercial-flight airport has its own fire station, within a few seconds’ drive of the runway. A fire crew is standing by, every time you take off or land. That’s based on What if? thinking. What if five minutes from now, a plane comes in hard, and has a post-touchdown fire, which could threaten the passengers trapped inside? What if an airplane’s engine catches fire on the runway, and a hundred passengers have to get off all at once?

Every pilot has heard the following exchange over the radio, more than once: A pilot announces an unusual circumstance—say, a need for a quick return to the departure airport after takeoff, because something’s wrong with the airplane, or a forced landing because of a mechanical problem or onboard emergency. Once the pilot explains the situation, the next words from the controller will inevitably be: “Flight XXX, cleared for landing, runway YYY. Do you require equipment?”

This last phrase means: Should the fire truck and rescue vehicles roll out to the taxiway? It’s a way of asking, What if? (I’ve personally had to ask for unusual landings half-a-dozen times over the years, but so far have always been able to reply: “Negative, no equipment necessary.”) I’m sure there are airports where the “equipment” has never been used in a real emergency, or not in many years. But it’s there and ready, every minute, because: What if?

What if? is the idea behind the certification and inspection of airplanes, and regular testing and training of pilots. At the design stage, the question is: What if the main navigation systems fail? Well, there are these backup systems. What if one engine goes out? Well, here is the other engine(s) that would keep the plane aloft. (It is obvious that a failure of What if? procedures—on the part of Boeing and the FAA and some airlines—lay behind the 737 Max disasters.) At the operators’ level every pilot, before every training or check flight, knows that most of it will involve responses to What if? What if your engine failed right now, and you had to land? What if all your electric equipment failed, right now? What if the airport where you’re about to land gets closed, right now, because the plane you’re following has a bad landing and is blocking the runway? What if, what if, what if?

Because of this thinking, commercial airplanes are remarkably safe (with the 737 Max an exception illustrating the rule), commercial airports are remarkably well prepared, and commercial pilots are remarkably competent. And because of a failure of What if? thinking, we have the countless governmental failures of the coronavirus era, including the disease-control catastrophes at major U.S. airports over the past 24 hours.

When it comes to public-health protections, it’s obvious which should be the guiding principle. It should not be the airlines’ cheese-paring approach to customer service: What’s the least we can get by with in normal circumstances? Instead it should be the aviation-safety question, What if?

At America’s busiest airports yesterday, we saw the consequences of “minimum necessary” thinking in What if? circumstances. The Trump administration decided to ban travel by most foreign nationals who had recently been in Europe, as a way to reduce exposure to and spread of the coronavirus.

The people in charge of the policy apparently thought: Here’s a way to minimize infection from foreigners. Judging by results, they didn’t ask or think about the next round of What if? questions:

What if everyone (naturally) rushes to get back at the same time, before airlines cancel even more flights? What if the flood of passengers swamps the airport’s normal capacity, and so ends up in big lines: lines in the jetway to get off the planes, lines at passport clearance, lines for baggage collection and Customs, lines—ah, the bitter irony—for medical screening, to separate out those who have been in high-infection zones? What if some or many of the people in these jammed lines were already infected? What if the hundreds of people packed together for hours in these scrums lost all “social distance,” from countless strangers, while penned up?

Cheryl Benard, who got stuck in the lines at Dulles Airport, chronicled the resultant chaos in The Washington Post:

When I inched closer to the front, I could see that a scant six immigration desks were in service. Two additional desks to the left had less traffic. These are ordinarily for people in wheelchairs; now, the wheelchairs were mixed in with the rest. When I asked a security guard about the other lines, he told me they were for people with a confirmed corona diagnosis. There was no separation for this group—no plastic sheets, not even a bit of distance. When your line snaked to the left, you were inches away from the infected.

This isn’t the first time public disasters have flowed from a failure to ask What if? (For instance: What if we’re not “greeted as liberatorsafter invading Iraq?) But this was a failure that stood for many others in the current administration’s approach, and itself may have significantly speeded spread of the disease.

I suspect that airport photos taken in the past 24 hours will figure in upcoming histories of our current plague year. For every infection that was prevented and life that might have been saved through the impending travel ban, I would bet there was enormously more damage the other way, through the enforced panicky crowding of people fleeing high-infection zones. All because no one asked: What if?

Lowly air-traffic controllers, airplane inspectors, or airport managers know they would be fired for comparable negligence. Asking the questions on which others’ safety depends is their professional responsibility. It is supposed to be a president’s responsibility as well.

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