Trees around airports may penetrate the airspace surfaces established to maintain safe aircraft operations. The traditional method for monitoring tree growth is through surveys, which are often expensive. If a survey has not been conducted in recent years, potential obstructions from tree growth could go unidentified, and could potentially contribute to an accident and possible liability exposure that can lead to a reactive approach. The issue is often more pressing at small airports with resource limitations that impact the monitoring and control. Alternative practices and new technologies, such as the use of unmanned aerial systems (UAS), light detection and ranging (LiDAR) or photogrammetry may provide more cost-effective solutions for gathering data. Once data is collected, there are strategies an airport can utilize that have varying costs and benefits. Other ACRP reports have studied airspace and obstruction issues, however, there is no in-depth discussion of tree management and analysis related to obstruction issues.
Understanding all methods that are available allows airports to effectively balance the safety of operations and community interests. Research is needed to identify new technologies and practices to determine their effectiveness for monitoring and managing tree growth.
The objectives of this research were to create a guidebook that (a) identifies and evaluates alternative methods for obstruction related data collection and analysis, and (b) includes strategies that effectively monitor and manage tree growth in and around airports. The guidebook should be applicable to different types, locations, and sizes of airports. The methods and strategies identified should be evaluated based on effectiveness, accuracy, ease of use, cost, training/expertise requirements and other relevant factors.
The guidebook includes:
- Methods of reporting data, validation of data collected, and action taken with appropriate stakeholders;
- A benefit cost analysis for alternate methods of mitigation (e.g., installation of light fixtures above the trees);
- Different types of new technologies used for identification of existing or anticipated tree encroachments into the protected surfaces, (e.g., UAS, LiDAR, geographic information systems (GIS) software);
- Different strategies to categorize the data and implement mitigation plans or actions;
- Challenges with community issues;
- A brief overview of protected airspace; and
- Identification of case studies evaluating alternative methods of surveys compared to traditional methods.
Status: This project is complete. This is expected to be published 2nd quarter 2023.