Preliminary Gap Analysis and Research Roadmap for Unmanned Aircraft Weather Decision Support

The use of Unmanned Aircraft System (UAS) operations in the National Airspace System (NAS) is rapidly expanding for a variety of commercial applications (e.g., package delivery, communications, and inspection operations) and for urgent public safety operations (NPFA, 2019). Research by the FAA and NASA is underway to develop Detect and Avoid (DAA) systems, geofencing systems, and Unmanned Traffic Management (UTM) separation services to provide safe airspace use by both UAS and conventional air vehicles (Lester and Weinert, 2019). The FAA NextGen program has issued an initial concept of operations for UTM (FAA, 2018) that discusses responsibilities for considering weather impacts on operations. An integral part of the FAA concept for a UTM ecosystem is UAS service suppliers that coordinate and distribute weather data to appropriate entities such as the remote pilot in command of the UAS. However, the details of what type of weather needs to be provided are not addressed in the concept of operations.

The unique characteristics of typical UAS vehicles (e.g., operations over populated areas at altitudes below 500 feet, constraints on speed and climb rate, and extreme sensitivity to precipitation, winds, turbulence, and icing) warrant a focused consideration of weather decision support for low altitude UAS operations in populated areas including near major airports.

This paper presents a preliminary identification and assessment of gaps in current weather decision support for UAS operations that was performed through a set of surveys and interviews with more than 90 UAS operators (Campbell, et al., 2017a) together with recommendations for improving weather decision support for UAS operations.

A total of 12 major weather information gaps were identified and prioritized based on the importance of the weather phenomena to UAS operations and the current availability of weather information to UAS operators. A key finding was that typical current weather observations and forecasts tailored for on-airport operations are not necessarily sufficient for low-altitude, off-airport operations: surveyed users indicated that airport-specific weather information does not readily translate to conditions at remote launch locations influenced by local terrain, vegetation, and water sources.

Moreover, the survey results show that significantly less weather information is available to support low-altitude off-airport flight than for typical manned-flight profiles. The lack of observations of ceiling, visibility, and winds near most low altitude UAS operational locations causes the validation of numerical weather forecasts of weather conditions for those locations to be the highest priority. Hazardous weather alerting for convective activity and strong surface winds are a major concern for UAS operations that could be addressed in part by providing UAS operators with access to the FAA’s existing real-time conventional aircraft weather decision support products along with appropriate training information.

Building off of the gap analysis, an initial roadmap was recommended for research (Campbell, et al., 2017b). There are 14 specific phased recommendations that define the roadmap. These range from near-term data collection efforts leveraging existing UAS test sites and operations (especially time urgent public safety operations) to longer-term research and development of UAS-specific weather impact models and forecasts.

Subsequent to the development of the roadmap, it was recognized that there are significant synergies between weather decision support especially for low altitude UAS operations, Urban Air Mobility operations, Helicopter Emergency Medical Service (HEMS) operations, and conventional aircraft airport operations that offer the opportunity for cost-effective enhancements in both safety and efficiency. Additionally, there are opportunities for improved weather observations using these various air vehicles as mobile sensors. These additional opportunities for improved weather sensing and decision support will also be discussed.

References

National Fire Protection Association, 2019, “NFPA 2400 Sstandard for Small Unmanned Aircraft Systems (sUAS) Used for Public Safety Operations).

Campbell, S. D., Clark, D. A., Evans, J. E., 2017a, Preliminary Weather Information Gap Analysis for UAS Operations, Project Report ATC-437, MIT Lincoln Laboratory, Lexington, MA.

Campbell, S. D., Clark, D. A., Evans, J. E., 2017b, Preliminary UAS Weather Research Roadmap, Project Report ATC-438, MIT Lincoln Laboratory, Lexington, MA.

Ed T. Lester and A. Weinert, 2019, "Three Quantitative Means to Remain Well Clear for Small UAS in the Terminal Area," 2019 Integrated Communications, Navigation and Surveillance Conference (ICNS), Herndon, VA, USA, pp. 1-17.

FAA, 2018, Concept of Operations for Unmanned Aircraft System (UAS) Traffic Management (UTM). V1.0.

-----

DISTRIBUTION STATEMENT A. Approved for public release. Distribution is unlimited. This material is based upon work supported by the Federal Aviation Administration under Air Force Contract No. FA8702-15-D-0001. Any opinions, findings, conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the Federal Aviation Administration.