Terrorism and measuring the risk of air travel January 7, 2010Posted by jonathanpenn in news.
In the wake of the Dec 25 “Christmas bomber” (aka “underwear bomber”) incident, there’s been a lot of conversation around safety of air travel. I’ve seen several articles and posts that repeat the old argument that air travel is safer than car travel, or even simply safer than ever.
I don’t want to get into why the air travel versus car travel comparison is faulty. But the “air travel being safer than ever” statement is measuring probabilities based on the number of flights and the number of incidents. That sounds reasonable at first glance, but I believe it is inappropriate in this circumstance. If one were measuring indiscriminate events such as equipment failures or flying into a flock of birds, such calculations might hold. But terrorist attacks are different. Terrorist attacks are planned, and planned with a purpose. Because of this, you cannot think of them as randomly occurring along some even distribution curve.
These terrorist attacks in the air aren’t designed to bring down our commercial aviation industry; they are designed to instill fear in the general populace. So on Dec 26, 2009, the odds of a terrorist attack would be quite low: besides the fact that security is heightened, fear has already been instilled, so the terrorists don’t need to do anything. On the other hand, we have determined, resourceful enemies which collectively presents a new threat that wasn’t there ten years ago. You can’t just say that because there are more flights than 10 years ago, that the skies are safer even in light of a few successful or attempted attacks. The specific situational aspects of the issue are everything.
I’m not saying the skies are unsafe. But simply tallying up the number of incidents or fatalities and dividing by the number of flights or miles (or, even worse, “passenger-miles”) doesn’t give you an accurate picture of the situation.