A study recently published by Volpe, The National Transportation Systems Center, provides a deeper understanding of the broader trends that impact the severity of runway incursions. Runway incursions, which are the unauthorized presence of vehicles, pedestrians, or aircraft on runways, can range in severity from creating a tarmac delay to causing a collision.

The Volpe study is a regression-based analysis of runway incursions and the broader trends that contribute to incursion severity. Volpe's analysts combined multiple data sources from the Federal Aviation Administration and weather data from Plymouth State University to create a comprehensive picture of all runway incursions that occurred in the United States between 2001 and 2010.

"Nobody has ever combined these data sets for this type of analysis before. Research on runway incursion often takes a narrative-based approach," said Garrett Hagemann, a Volpe economist. That sort of storytelling is useful in explaining the causes of an isolated runway incursion incident, but it does not illuminate the broader trends that may have an effect on the severity of runway incursions. "Examining a large number of incidents allows conclusions to be drawn about incidents in general, rather than a specific event," said Hagemann.

"This type of research allows the FAA to prioritize their safety efforts. The FAA can better target their interventions for maximum improvement," said Lee Biernbaum, Volpe project manager. For instance, incidents resulting from a controller error tend to be more severe than incidents resulting from a pilot or vehicle-operator mistake. The research also shows that incident type and severity may vary by region, indicating that policy impacts may also vary by region.

Volpe's research provides concrete evidence that there is a significant human component to runway incursions. In the nine-year data set that was analyzed, there were no severe incursions by pilots with more than 5,000 hours of flying time in the same make and model plane. Increased controller workload led to an observed increase in incursion severity, whereas there was no indication that controller age impacted incursion severity.

Volpe economists Lee Biernbaum and Garrett Hagemann were involved with the project. The report is available in the National Transportation Library.