Runway determination using two-point time difference method

Around airports having multiple runways, aircraft noise affected areas vary depending on the runway operation because the flight path changes by the operation. Therefore, it is important to figure out exactly which runway was used for analyzing the noise impact on the surrounding area. For this purpose, runway information included in flight data provided by the airport operator can be used in most commercial airports. However, for some airports, the data is unavailable or not always accurate. We developed "Takeoff/ landing runway determination system; DL-TLS" for determining runway operations and have been utilizing it to aircraft noise analysis. However, that system requires to place measurement stations at the end of each runway to ensure the high level of accuracy. To solve this issue, we focused on difference in acquisition time of the same transponder signal at two measurement stations. This new approach achieved satisfactory level of runway determination accuracy, by matching the time difference changes with template for each runway. We proved that this method can be used in combination with the current DL-TLS with even higher accuracy. In addition, we showed the possibility of reducing number of measurement stations and eliminating the measurement location constraint.