Perception of Risk in the Wake
of the Concorde Accident

The AirSafe Journal
Issue 14 - 1 August 2000
(Revised 6 January 2001)

On 25 July 2000, an Air France Concorde crashed shortly after takeoff from Charles de Gaulle airport near Paris. In the intense media coverage that followed the accident, one of the messages that was repeated by both the media and by aviation safety experts was the previous safety record of the Concorde and how it was unblemished by any previous major accident. A Washington Post online article from 26 July 2000 described the first Concorde crash in over 30 years of flight as the end of "the most remarkable safety reocord in aviation history." This perception was shared by many outside of the Washington Post, a perception that many having years of accident-free operation implies having a safe aircraft. While at first glance this may seem reasonable, on closer inspection this attitude ignores a fundamental aspect of risk -- that risk is a function of both the likelihood of a potential hazard and the likelihood that the hazard occurs.

In the case of the Concorde accident, the hazard was the loss of the aircraft and the associated loss of life. The Washington Post article implied that the potential hazard was the number of years that the Concorde fleet was in operation. Taking that attitude a bit further, it would imply that aircraft like the DC10 or 737, aircraft that have had many more fatal accidents over the same period, have a much less admirable record. In fact, a closer examination of records of various aircraft models tells quite a different story.

In another Washington Post article, published 30 July 2000, the former head of the accident investigation department at Boeing stated that the Concorde fleet had less than 80,000 flights in its history, a history that included no more than 14 aircraft. In contrast 737, the most common jet transport with over 3,700 aircraft produced since its inception, has had over 80 million flights.

So numerous are 737 flights that the worldwide fleet performs more flights every 10 days than that Concorde has over its entire history. However, it is highly unlikely that many aviation experts, or for that matter many airline passengers, would claim that the 737 had a remarkable safety record if there had been no crashes during the previous month.

The Concorde accident and the perception of the Concorde's previous record demonstrates why looking at the amount of time between accidents may be very misleading. AirSafe.com focuses on the number and severity of fatal events per million flights for two reasons: first, this kind of measure is consistent with the commonly used definition of risk. Second, it provides a more rational means of comparing different aircraft models. On the Fatal Event Rates for Selected Airliner Models page, one can compare different aircraft models based on their fatal event rates. This technique is described in more detail in the next issue of the AirSafe Journal.

As it turns out, the Concorde has the highest fatal event rate in the list, 12.5 fatal events per million flights. However, it also has by far the lowest number of flights among the models listed. This brings up an entirely different issue of whether the current Concorde rate is a fair measure of the underlying risk of a Concorde flight compared with a flight on other aircraft models. That is a question that will likely be addressed in another AirSafe Journal article.

Accident Description
The aircraft was on a charter flight from Charles de Gaulle airport near Paris to JFK airport in New York. There was apparently a series of problems involving the landing gear and at least one of the engines, problems that began either during takeoff or shortly after takeoff. The aircraft caught fire and crashed into a hotel in the town of Gonesse. All 100 passengers and nine crew members were killed. Four people on the ground were also killed.
Other accident details