Researchers at the Purdue Polytechnic Institute have developed a patent-pending, simplified light system to automatically indicate an airport runway’s status to pilots, pedestrians, and vehicle operators.
The solar-powered system is called Simple, Affordable, Flexible, and Expandable Runway Status Lights (SAFE-RWSL). It uses Automatic Dependent Surveillance-broadcast (ADS-B) data and computer vision to activate runway lights in real time.
John Mott is a professor and Luigi Dy is a doctoral student in Purdue University’s School of Aviation and Transportation Technology. They developed SAFE-RWSL and the Purdue Innovates Office of Technology Commercialization has applied for a patent to protect the intellectual property.
A six-minute presentation about SAFE-RWSL in its earliest prototype form is available on Dy’s YouTube channel. His dissertation that covers the human-factor issues related to the effectiveness of SAFE-RWSL is published online.
“Based on the performed study, the use of simplified runway status lights is expected to be effective at reducing runway incursion risk in non-towered, no-traffic environments when a conflicting aircraft is difficult to see,” he said.
Limitations of traditional runway surveillance systems
Radar-based detection systems are the standard to prevent runway incursions. The cost usually limits their use to larger airports — the current baseline system costs tens of millions of dollars, according to the researchers.
“Small airports generally rely on simple ‘see-and-avoid’ procedures or, in limited cases, air traffic controllers to prevent these incursions,” Mott said. “Without a comprehensive approach that incorporates technology, however, even the most vigilant pilots and air traffic controllers, if available, can’t prevent all potential accidents resulting from encroachments on an active runway by pedestrians, ground vehicles or other aircraft.”
Current systems used for runway surveillance also can be complex to implement. They often require expensive infrastructure such as electrical systems, pavement reconstruction, or additional equipment installed in aircraft and vehicles.
“ADS-B technology is already mandated for aircraft in most types of U.S. airspace, making it widely available,” Dy said. “As a result, the SAFE-RWSL system is a low-cost, easy-to-integrate option for airports of varying capacities to improve runway safety and reduce risks of incursions.”
The prototype SAFE-RWSL system was tested at Purdue University Airport (KLAF), where the researchers observed 123 aircraft operations and compared them to detections.
“The system accurately detected 94% of aircraft, including all operations involving ADS-B-transmitting aircraft. It also sufficiently provided timely runway status information despite being in airspace where ADS-B is not required,” Dy said.
To train, develop, and evaluate the effectiveness of the SAFE-RWSL’s computer vision component, Mott and Dy utilized a sample of recorded images of aircraft operations. Based on almost 3,400 seconds of ground operations, the system accurately detected 94% of operations, according to the researchers.
“Using object detection and filtering algorithms, the computer vision software designed to run on solar-powered modules was able to detect 110 out of 110 approaching aircraft, while providing sufficient time to indicate potential traffic conflicts,” Dy said. “Our next step to develop the computer vision subsystem of SAFE-RWSL is to conduct live tests of aircraft on runways.”
Mott and Dy have also conducted economic feasibility projections on the system.
“We estimate a production SAFE-RWSL system to cost no more than an order of magnitude less than existing systems, enabling it to be applicable to more airports than existing systems,” Dy said. “Initial projections showed an expected 10-year benefit-to-cost ratio of 2.37.”
Mott and Dy are developing a second-generation prototype to demonstrate to airport officials.
“We hope to get further funding from interested parties to continue to improve and test the system in different environments,” Dy said. “We hope that the system will eventually be accepted by the FAA as a solution for runway incursion mitigation.”
For more information: Purdue.edu
