Understanding Overflight Travel Patterns Above Parks and Protected Areas: A Systematic Review

This systematic review is the first summary of existing research conducted to advance understanding of overflight travel patterns above parks and protected areas —information that is important for understanding how to monitor, manage, and estimate landscape scale noise disturbances from aircraft. We found that while research on overflight travel patterns is expanding, it has primarily been conducted in the United States. These studies showed that logging Automatic Dependent Surveillance-Broadcast (ADS-B) data is a common and effective method for tracking overflights. These data are similar to GPS data in that they include longitude (x-coordinate), latitude (y-coordinate), altitude (z-coordinate), and a unique identification code. Like other types of travel patterns, such as visitors hiking in protected areas, overflight patterns can be analyzed to yield both site-specific insights and broadly generalizable conclusions. In this study, we apply a spatially conditioned travel patterns framework to organize general findings and enhance understanding of how spatial context informs the measurement and management of overflight activity. The two primary strategies for managing airspace above protected areas were found to have spatial (i.e., lateral and vertical offsets) and temporal components. It’s also critical to consider overflight altitudes using above mean sea level, for understanding regional trends, and above ground level, for contextualizing flights over variable local terrain and terrestrial resources. Overall, this review shows that efforts to examine overflight travel patterns are increasing, can inform managers about the acoustic environment, are a foundational component for developing management strategies related to aircraft noise impacts, and have the potential to be combined with other types of data such as acoustic recording data, social science data, and other travel patterns (e.g., wildlife, terrestrial visitors) to more robustly understand impacts related to overflights.