Using ADS–B Data to Understand Overflight Altitude Characteristics at Hawai'i Volcanoes National Park.

Air tour management plans for U.S. national park units are developed by the Federal Aviation Administration (FAA) and the National Park Service (NPS). The FAA recommends pilots fly higher than 2,000 feet above ground level (AGL) over parks, wildlife refuges, and areas with wilderness characteristics. Management of air tours is important for mitigating visual and noise impacts. Understanding air tour travel patterns has been problematic because objective location data have been difficult to obtain. A newer technology, Automatic Dependent Surveillance–Broadcast (ADS–B), can be used to accurately track overflights. Prior ADS–B studies of air tours conducted limited analysis with respect to altitude characteristics. Thus, the purpose of this study was to determine how overflights spatially vary across altitudes and determine altitude trends for primary flight corridors. Results suggest overflights trend along the east side of the park and 74.59 percent of waypoints within a 0.5-mile buffer around the park boundary had altitudes less than 2,000 feet above ground level (AGL). Results revealed that as altitude increased, overflight density decreased. Using hot spot clustering analysis, overflight lateral pattern differences were determined for altitudes lower than 2,000 feet AGL compared to altitudes higher than 2,000 feet AGL. This study also identified one primary flight corridor with average altitudes mostly below 2,000 feet AGL. Managers can use these results to inform the development of air tour management plans and monitor compliance. [ABSTRACT FROM AUTHOR]