UAS Integration in the NAS (ASCI 638, 3.6)

The quantity and frequency of Unmanned Aerial Systems (UAS) use is growing across the United States as more markets realize the many benefits, such as low cost, endurance, or human safety. Since 2012, the Federal Aviation Administration (FAA) has been modernizing the National Airspace System (NAS) under the Next Generation Air Transportation System (NextGen) initiative, which is expected to be complete by 2025. The following essay reviews NextGen as it applies to UAS and their human factors.

NextGen Goals and Improvements

NextGen has the overarching goals of increasing safety, efficiency and sustainability through collaboration and technology application. The Global Positioning System (GPS), and voice and data communication networks form the backbone of the new system. NextGen is truly a “system of systems,” with four focus areas (FAA, 2017). Automation includes a suite of applications for data sharing between dispatchers, crews, and controllers that support real-time collaboration and decision-making to efficiently work through the dynamic aviation environment. Enterprise Information Management is the network architecture beneath the user and automation layers that ensures data is reliably disseminated in a common language. Communication focuses on replacing 12 antiquated ground systems with a common internet-protocol-based system. Additionally, digital datalinks will be used to send flight plans and clearances, significantly reducing line-of-sight radio communication. Lastly, Surveillance seeks to replace traditional wide area radar tracking with Automatic Dependent Surveillance-Broadcast (ADS-B). ADS-B “out” will replace traditional Mode 3 transponders and transmit GPS position, velocity, and other data. ADS-B “in” users will be able to receive traffic, weather, and advisory data from FAA ground stations. Overall, these four focus areas will guide improvement to the NAS that is forecasted to save airlines and the FAA over $11 billion in operating costs and avoid over $22 billion in economic losses (FAA, 2015).

UAS integration with NextGen

The Next Generation Air Transportation System Joint Planning and Development Office (JPDO, 2012) has published a roadmap outlining the activities needed for full integration by 2030. UAS are poised for NextGen integration, since they are inherently a digital system that already generates much of the data needed by automation, communication, or surveillance functions. The MITRE Corporation has investigated the “communications” and “airspace operations” challenges further and highlighted the need for interoperability standards, recommending STANAG 4586 due to its already wide-spread use, along with an example airspace clearance process (Paczan, Cooper, Zakrzewski, 2012). Specifications for hardware integration will likely be driven by the size, range, and mission of the UAS. One question that affects all is where the UAS (which includes the vehicle, control station, and operator) will interface with NextGen: at the vehicle, ground control station (GCS), or a combination of the two. An airborne vehicle can extend the communication range of an un-networked GCS, although a networked GCS can have near infinite range. The solution will need to be a function of GCS mobility, onboard, communication capability, and lost-link logic. One of the most challenging aspects of UAS integration is satisfying sense-and-avoid (SAA) requirements. Marshall, Barnhart, Shappee, and Most (2016) explore the various hardware options, ranging from stereo optical sensors to radar, although the largest challenge may be changing FAA culture. Aircraft certification has historically been based on satisfying equipage mandates or system tolerances, however this may not be appropriate for the wide range of UAS. For example, an SAA radar requirement would ensure that small UAS would never be able to comply. Instead, requirements need to be levied as a desired end-state, such as detecting and avoiding intruding traffic with a given time margin and slant range separation.

Human Factors Considerations

Human factors considerations for UAS integration with NextGen need to cover both the GCS and air traffic controller consoles. With full implementation of the system in 2025, pilots/operators and controllers will need properly designed displays to process, filter, and correlate the tremendous amount of data. Of note, the JPDO integration roadmap specifically calls for research in human-automation interaction, with an emphasis on creating pilot-centric GCSs, an area which has historically been deficient. The wide range of pilotless vehicles and missions will again drive the need for goal versus tolerance-oriented certification standards. Paczan, Cooper, Zakrzewski (2012) proposed standardized clearance instructions that would be recognized and displayed by all GCSs, such as a two-minute instrument hold at the next waypoint in the mission.

Conclusion

This short essay has conducted a review of the available literature on UAS integration with NextGen, as they will need to be by 2025. The overall system was studied to gain an understanding for UAS and their associated human factors, while gaining appreciation for the wide range of challenges that required detailed analysis.

References

Federal Aviation Administration. (2017, January 12). Next Generation Air Transportation System (NextGen). Retrieved from https://www.faa.gov/nextgen/

Federal Aviation Administration. (2015). NextGen Works for Airlines. Retrieved from https://www.faa.gov/nextgen/library/media/getSmart_airlines.pdf

Marshall, D. M., Barnhart, R. K., Shappee, E., & Most, M. (2016). Introduction to unmanned aircraft systems. Boca Raton: Taylor & Francis, CRC Press.

Next Generation Air Transportation System Joint Planning and Development Office. (2012). NextGen UAS Research, Development and Demonstration Roadmap. Retrieved from https://fas.org/irp/program/collect/uas-nextgen.pdf

Paczan, N., Cooper, J., & Zakrzewski, E. (2012). Integrating UAS in NextGen Automation Systems. Retrieved from https://www.mitre.org/sites/default/files/pdf/12_3347.pdf