FiveThirtyEight: Politics Done Right: The Odds of Airborne Terror
The Bureau of Transportation Statistics provides a wealth of statistical information on air traffic. For this exercise, I will look at both domestic flights within the US, and international flights whose origin or destination was within the United States. I will not look at flights that transported cargo and crew only. I will look at flights spanning the decade from October 1999 through September 2009 inclusive (the BTS does not yet have data available for the past couple of months).
Over the past decade, according to BTS, there have been 99,320,309 commercial airline departures that either originated or landed within the United States. Dividing by six, we get one terrorist incident per 16,553,385 departures.
These departures flew a collective 69,415,786,000 miles. That means there has been one terrorist incident per 11,569,297,667 mles flown. This distance is equivalent to 1,459,664 trips around the diameter of the Earth, 24,218 round trips to the Moon, or two round trips to Neptune.
Assuming an average airborne speed of 425 miles per hour, these airplanes were aloft for a total of 163,331,261 hours. Therefore, there has been one terrorist incident per 27,221,877 hours airborne. This can also be expressed as one incident per 1,134,245 days airborne, or one incident per 3,105 years airborne.
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