Runway collisions at towered American airports could kill 700-800 people and injure 200 more over the next two decades, according to a paper being presented at a convention of the Institute for Operations Research and the Management Sciences (INFORMS®).
The paper, Runway Collisions: Crying Wolf? is by Arnold I. Barnett, George Eastman Professor of Management Science at MIT's Sloan School of Management, and Gary Paull of MCR Federal in Burlington, MA. They will speak in San Antonio's Henry B. Gonzalez Convention Center on Monday, Nov. 6.
Barnett and Paull performed their research under a contract from the Federal Aviation Administration. They emphasize that their projection could be pessimistic because it does not consider the benefits of various initiatives-technological and otherwise-now underway in the US that aim to prevent runway collisions. They note that the FAA and the National Transportation Safety Board have described reducing the risk of runway collisions as their number one priority.
Surprising and Disturbing
"The estimates we reached are surprising and disturbing," say the authors. "Recent patterns indicate roughly 15 fatal runway collisions over 2003-2022 at towered US airports. Most of these accidents would involve at least one large jet plane.
"Such numbers are all the more unnerving because, over 1997-99, there was only one fatal event on a US domestic jet, which killed 11 people. It is therefore conceivable that US runway crashes over 2003-22 could cause more deaths and serious injuries to US jet passengers than all other causes combined."
The calculation that towered airports would suffer 15 fatal runway accidents through 2022 implies a rate per decade nearly twice as high as the recent rate. The jump reflects a projected increase in air traffic over the period, which is all the more dangerous because of strong evidence that the risk of runway collisions varies with the square of the amount of traffic. In consequence, the risk grows at a faster rate than the traffic itself.
Barnett and Paull base their "status quo" (no improvement) forecast on data about US runway collisions, fatal runway crashes worldwide, recent runway incursions that were viewed as especially dangerous by pilots and air traffic controllers, airport-specific weather patterns, and projected growth in air traffic.
Reduced Visibility is Key Factor
The study focuses on 449 domestic airports that have air traffic control towers. The FAA has announced plans for enhanced collision-warning technology at 59 busy towered airports. The 20-year period starting in 2003 was chosen for the study because this is the projected deployment date for the new systems and their expected life span. The "baseline" projections that the researchers made did not consider the life-saving potential of such technology. Instead, the projections were part of the FAA's analysis that led to its decision to deploy the new ASDE-X radar at 25 airports, in addition to the ASDE-3/AMASS radar systems already in place at 34 airports.
Barnett and Paull factored into their analysis a review of collisions at towered airports over 1983-1998, which revealed a striking pattern: All such collisions, including those that did not result in injury or death, occurred during conditions of reduced visibility - at night, during the glare of sunrise or sunset, or during fog or haze. In forecasting the death toll, the paper examines worldwide data, which shows that an average proportion of those killed about a large jet involved in a fatal runway collision was 40%. For planes other than large jets, the average death rate in such collisions was 71%. In fatal runway collisions, 54% of the planes involved were large jets; 14% involved one plane and a land vehicle. On average, a large jet involved in a US runway collision would carry approximately 110 people while other planes carry an average of 15 people.
Although the estimates of 700-800 deaths may be alarming, the risk to individual flyers is small given forecasts that nearly 20 billion passengers will fly in the US over 2003-2022. The risk to the average flyer would be about 1 in 25 million per flight, according to the researchers.
"Nevertheless," Prof. Barnett states, "it is unimaginable that Americans would ever be comforted by the estimate that "only" 800 travelers would perish. Those who warn about runway collisions are not crying wolf; rather, they reflect the foresight that has made aviation safety in Westernized nations the eighth wonder of the world. There is no doubt that the threat of runway collisions is receiving urgent attention by government and industry. If recognizing a problem is halfway to solving it, then we have easily reached the 50% mark in averting disasters on the runway."
The theme of the INFORMS convention is "Integrating Theory and Application 2000." The convention will include sessions on topics applied to numerous fields, including commuter transit, e-commerce, health care, information technology, energy, transportation, marketing, telecommunications, and sports. More than 1,500 papers are scheduled to be delivered. The General Chair of the convention is Dr. Way Kuo, Texas A&M University. Additional information about the conference is at http://www.informs.org/Conf/SanAntonio2000/ and http://www.informs.org/Press.
The Institute for Operations Research and the Management Sciences (INFORMS®) is an international scientific society with 10,000 members, including Nobel Prize laureates, dedicated to applying scientific methods to help improve decision-making, management, and operations. Members of INFORMS work in business, government, and academia. They are represented in fields as diverse as airlines, health care, law enforcement, the military, the stock market, and telecommunications. The INFORMS website is at http://www.informs.org.