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How Risky Is Flying?

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<p>Trying to judge whether a particular risk is big or small is, well, a risky business. There's a lot more to it than you might think. Flying in airplanes is a case in point. You'd think that you could just find out the numbers—the odds—and that would be it. The annual risk of being killed in a plane crash for the average American is about 1 in 11 million. On that basis, the risk looks pretty small. Compare that, for example, to the annual risk of being killed in a motor vehicle crash for the average American, which is about 1 in 5,000.</p><p>But if you think about those numbers, problems crop up right away. First of all, you are not the average American. Nobody is. Some people fly more and some fly less and some don't fly at all. So if you take the total number of people killed in commercial plane crashes and divide that into the total population, the result, the risk for the average American, may be a good general guide to whether the risk is big or small, but it's not specific to your personal risk.</p><p></p><p></p>
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<figcaption><p>This table, which compares the risk of accidental death during various modes of travel, shows that flying is still much safer than most other forms of transportation. © WGBH Educational Foundation, data courtesy U.S. Department of Transportation/PHMSA.jpg</p>
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<p></p><p></p><h3>Figuring the risk</h3><p>Then there's another numbers problem: What denominator are you using? (For the math-challenged, like me, that's the number at the bottom of a fraction.) You can calculate the risk of flying by:</p><ol><li>Dividing the number of people who die into the total number of people, which gives you the risk for the average person;</li><li>Dividing the number of victims into the number of total flights all passengers took, which gives the risk per flight;</li></ol><p>or</p><ol><li>Dividing the number of victims into the total number of miles all of them flew, which gives you the risk per mile.</li></ol><p>They all produce accurate numbers, but which one is most relevant to you depends on your personal flying patterns. Some fliers take lots of short flights and some take longer ones, for example. Since the overwhelming majority of the few plane crashes that do occur take place in connection with takeoffs and landings, the risk is less a matter of how far you fly and more a matter of how often. If you're a frequent flier, then the risk per flight means more. For occasional long-distance fliers, the risk per mile means more. A frequent, long-distance flier would want to consider both.</p><p></p>
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<figcaption><p>The number of plane crash fatalities in the United States varies widely from year to year, as this graph shows. © WGBH Educational Foundation, data courtesy National Transportation Safety Board</p>
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<p></p><p></p><h3>A matter of time</h3><p>Here's another number problem with the risk of flying: Do you calculate the risk on the basis of one year, or an average of five years, or 10, or 20? Most years no plane crashes occur, or at least very few. So the number of victims per year goes up radically in years when there are crashes. Just look at the spikes in the number of deaths from plane crashes by year in the graph above.</p><p>Risk perception is not just a matter of the facts.</p><p>So to calculate the risk per year can be misleading. One really bad year would skew the numbers toward the more frightening. A year with no crashes makes it look like it's zero. But if you average things over, say, five years, or 10, some other factors muddy the waters. In the last five years safety factors have changed. Advanced weather radar has been installed near major airports, and new FAA rules have gone into effect. A 10-year average might be misleading too. It would include the aberration of September 11, 2001.</p><p>Despite all these caveats, numbers are a great way to put risk in general perspective, and there is no question that by most metrics, flying is a less risky way to travel than most others. But wait: Just when you thought it was safe to use numbers to put risk in perspective... Numbers are not the only way—not even the most important way—we judge what to be afraid of. Risk perception is not just a matter of the facts.</p><p></p><p></p>
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<figcaption><p>David Ropeik is an instructor in risk communication at the Harvard School of Public Health. He is coauthor (with George Gray) of <i>Risk!: A Practical Guide for Deciding What's Really Safe and What's Really Dangerous in the World Around You. </i>Image Credit: David Ropeik</p>
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<h3>Fear factors</h3><p>It's also a matter of the other things we know (e.g., airline companies are in financial trouble) and our experiences (maybe you took a really scary, turbulent flight once) and our life circumstances (my wife was more afraid of flying when our kids were little). And on top of all that, several general characteristics make some risks feel scarier than others.</p><p>Researchers in psychology like Paul Slovic and Baruch Fischhoff have found that when we have control (like when we're driving) we're less afraid, and when we don't have control (like when we're flying) we're more afraid. That probably explains why, in the first few months after the 9/11 attacks, fewer people flew and more people chose to drive. Driving, with its sense of control, feels safer. Studies at Cornell and the University of Michigan estimate that between 700 and 1,000 more people died in motor vehicle crashes from October through December of 2001 than during the same three months the year before.</p><p>Another "feelings factor" that informs our perception of risk is awareness. The more aware of a risk we are, the more concerned about it we are. Which explains why, when there is a plane crash in the news, flying seems scarier to many of us, even though that one crash hasn't changed the overall statistical risk much.</p><p>Then there's the factor the researchers call dread.</p><p>People are also more sensitive about risks that are catastrophic, which kill people all at once in one place, than we are about risks that are chronic, where the victims are spread out over space and/or time. Plane crashes, therefore, get more media attention than, say, heart disease, which kills 2,200 people in the United States each day, just not all in one place at one moment.</p><p>Then there's the factor the researchers call dread, which is basically a measure of suffering. The more awful/painful/nasty a way to die it is, the more afraid of it we are likely to be. What happens to people in a plane crash feels pretty high up on a list of awful/painful/nasty ways to go. It sounds a lot worse—and scarier—than dying of heart disease, for example, even though the likelihood of dying from heart disease is much higher (1 in 400 per year, for the average American).</p><p>The challenge, then, in making an informed decision about the risk of flying, or any risk, is to balance these three components—the numbers about that risk (especially those that are most relevant to you), all the other things we know and our life circumstances, and the affective feelings the risk triggers. That way the choices we make, to fly or drive for example, will include what is right for each of us but will also hopefully be more in line with the scientific facts, and that should help us live healthier and longer lives.</p>
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<p data-block-key="sgz74">Harvard&#x27;s David Ropeik explains why judging risk is a risky business.</p>

How Do We Perceive Risk?

<p>Part of the reason the Newtown tragedy was so upsetting was because 20 of the victims were defenseless young children. Pictures of the victims perfectly capture their innocence and tender age. Hearing President Obama read their names in <a href="http://www.washingtonpost.com/politics/president-obamas-speech-at-prayer-vigil-for-newtown-shooting-victims-full-transcript/2012/12/16/f764bf8a-47dd-11e2-ad54-580638ede391_story.html" target="_blank">his address</a> in Newtown was heartbreaking. It is so unbearably tragic.</p>
<p>But where does that very real pain come from? Most of us don't know any of these kids or anyone in Newtown. They are as strange to us as the eight people shot to death last Sunday, for whom most of us feel no such pain. Why is this particular gun crime so heart-rending to people around the world?</p>
<h3>Shared Dangers</h3>
<p>The common pain comes, in part, from the fact that humans are innately more sensitive to anything that threatens or harms children than if the same risk only imperils adults. A risk to "future generations" is a risk to us all, a risk to the species. That makes a risk to kids—any kids—a shared danger that feels particularly threatening.</p>
<p>Other research into the psychology of risk perception has found additional factors that compound the emotional power of the Newtown shootings. One of them is the matter of scale and time frame. A risk that causes a lot of suffering or death in one place at one time, like the Sandy Hook shootings, is a "catastrophic" risk, and they worry us more than if the victims are spread out over space and time—a "chronic" risk—like those eight gun murders last Sunday. </p>
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<img alt="Group Threats" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/risk-perception-01.width-990_3dPgKo4.jpg"/>
<figcaption>Threats to a large number of people frighten us more than risks to individuals.
        
        <div class="credit">© Ints Vikmanis/iStockphoto</div>
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<p>That's one reason <a href="http://www.pbs.org/wgbh/nova/space/how-risky-is-flying.html">why plane crashes scare us more</a> than the much more likely risk of dying in a car crash. Another, pertinent to what happened in Newtown, is that risks beyond our control frighten us more than if we feel we have some power over the circumstances. Those innocent young children, and the six heroic staff members at the school who were killed as well, had no way to protect themselves against the guns and the multiple 30-bullet clips Adam Lanza used to slaughter his victims. Powerlessness makes any risk feel scarier, and it's hard to think of a clearer example of a defenseless victim than a 6-year-old cowering in front of a maniac in combat clothes with a loaded semi-automatic rifle.</p>
<h3>A Distinguishing Factor</h3>
<p>You can hear this risk perception psychology in the way we have been responding to the Newtown massacre. The demand for gun control is now more intense than after any of the eight other mass gun murders in the United States in 2012. And the National Rifle Association, absolutist opponents of any limits on guns even after all those other mass murders, now says "the NRA is prepared to offer meaningful contributions to help make sure this never happens again." As Connecticut Representative John Larson said, "the loss of innocence and the age of the children" distinguishes this tragedy from so many others. </p>
<p>President Obama emphasized the psychological factor of "catastrophic" risk in his statement the day of the massacre. "Since I've been President, this is the fourth time we have come together to comfort a grieving community torn apart by mass shootings," he said. "Whether it's an elementary school in Newtown, a shopping mall in Oregon, or a temple in Wisconsin, or a movie theater in Aurora... we're going to have to come together to take meaningful action to prevent more tragedies like this."</p>
<blockquote>Our sense of control will also play an important role in how we feel about Newtown.</blockquote>
<p>Consider, too, how the desire for control is influencing people's reactions to Newtown. Some gun rights advocates have said that the way to protect kids in school is to arm teachers. The parents of a sixth grader in Utah sent him to school Tuesday with an unloaded handgun and ammunition so he could protect himself, and to give him—and his parents—a reassuring sense of control. Bullet-proof back packs are selling briskly. And in the face of possible future limits on the availability of assault rifles guns, gun sellers report that those weapons are flying off the shelves.</p>
<p>Our sense of control will also play an important role in how we feel about Newtown because of something called the <a href="http://www.culturalcognition.net" target="_blank">cultural cognition</a> of risk. Research has found that we shape our views so they agree with those in the groups with which we most closely identify. That way the group embraces us as a member in good standing, which is a key consideration for social animals like us that depend on our group and larger community for protection and well-being. (This is why various forms of social rejection, including the fear of flopping as a public speaker, always make the top ten "most afraid of" lists.)</p>
<h3>Cultural Subtleties</h3>
<p>Cultural cognition has found that people organize themselves into subconsciously defined groups based on our preferences for how society ought to operate. One of those groups, which researchers call individualists, prefer to live in a society that maximizes individual freedom and choice. Another is known as communitarians, who prefer a society that operates under more of a "we're all in this together" sort of approach. They advocate sacrificing some individual freedoms for the greater common good.</p>
<p>Regarding Sandy Hook, communitarians are likely to be more upset by the tragedy because that gut-wrenching feeling motivates them to fight more strongly for societal limits on individual gun rights, a communitarian view. Individualists, on the other hand, while still grieving the loss of the children, are likely to feel differently about Newtown because they don't want to magnify threats to individual rights or move away from the freer society that they prefer.</p>
<p>The massacre in Newtown needs no psychological deconstruction to explain why it feels so awful. But the lessons we can learn are informative because they illuminate how our attitudes about risk are informed not just by the facts, but how we feel about those facts. As valid as our feelings are, they sometimes contribute to personal choices and social policies that respond <em>more</em> to feelings than to facts, and that can challenge our ability to make the healthiest choices for ourselves and our kids, whether the risk is guns, climate change, food poisoning, or anything else.</p>

Why mass murders and other tragedies that kill scores of people make us most fearful.

David Ropeik

Articles

How Risky Is Flying?

How Do We Perceive Risk?

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