Unmanned Aircraft Systems

Unmanned Aircraft Systems and Deconfliction
The global aviation community has experienced significant advancements in the recent past. Following these developments, Unmanned Aircraft Systems (UAS) have attained a critical mass in this community. Consequently, UAS operations have becomes a critical component and part of today’s global aviation community. According to Fern et al. (2011), UAS is increasingly used in combat zones, which has, in turn, generated mounting pressure and demands on airspace operations. As UAS become more common, their civil and military applications are faced with the need for decreasing levels of human involvement and supervision. This implies that there is an increased need for autonomy of UAS operations. In this regard, deconfliction has emerged as a suitable strategy for promoting the autonomy of UAS. This paper provides an overview of UAS and deconfliction in relation to the growing need for autonomy of UAS operations in civil and military applications.
Overview of UAS
UAS (Unmanned Aircraft Systems) is a system comprising aircraft with no onboard pilot, controlled remotely at an operating station (Congressional Research Service, 2016). The aircraft used in this system is sometimes known as a drone or an unmanned aerial vehicle (UAV). However, there are three basic types of aircraft, apart from missiles, that fly without onboard pilots. They are aircraft that fly in a repetitive manner and designed with limited flexibility, steered remotely at an operating station, and controlled by onboard navigation systems that maintain direction, altitude, and location. UAS falls under the category of aircraft controlled remotely from an operating station.
UAS applications have become common in civic and military aviation operations in the recent past. However, the public’s understanding of this system is largely shaped by the use of drone aircraft by the military in overseas conflicts. Military use of drone aircraft in combat operations can be traced back to World War I and II as the U.S. Army applied this technology for reconnaissance missions. Since its use in the First World War, UAS has remained an important part of military aviation operations. Over the past few decades, the use of UAS in civic aviation operations has gained more attention as rapid technological advancements continue to transform the aviation industry. Currently, unmanned aircraft are sold in the hobbyist and commercial marketplace though it is slightly different from military drones. According to Congressional Research Service (2016), unmanned aircraft in hobbyist and commercial marketplaces use other terminology like UAS because it is generally different from military drones.
The increased availability and use of UAS in civic operations are attributable to its potential in transforming the modern business environment. UAS has the capability to bring numerous changes in business operations as well as transform how government agencies operate. As a result, many companies and public-sector organizations are increasingly considering ways for productive and beneficial use of this system. This trend has been coupled with the design of new generations of UAVs by inventors. The rate of development and deployment of UAS across the globe has increased rapidly in recent years. In the United States, the rate of commercial use of this system continues to increase though UAVs have traditionally been used for military operations or applications. Additionally, the rate of development and deployment of this system in the country is influenced by the Federal Aviation Administration (FAA) regulations governing UAS applications in commercial and public-sector areas.
Challenges and Opportunities for UAS
One of the opportunities associated with the increased development and deployment of UAS is the potential to transform public-sector and commercial operations. UAS provides public-sector organizations and commercial enterprises with numerous opportunities to enhance business operations. This opportunity has contributed to the increased development and use of this system in commercial and public-sector organizations across the globe. For example, in 2009, nearly 20,000 UAV flights took place in civilian airspace, accumulating more than 2,500 hours (Gambold, 2011). This reflected the increase in development and use of these aircraft in the civilian airspace at it represented a tripling of UAP operations since 2007. Secondly, UAS has the opportunity of increased access to the National Airspace (NAS). The increased access to NAS is brought by the emergence of autonomous drones or multi-aircraft control systems. In addition, UAS has attained a critical mass in the global aviation community, which enhances the prospects of increased access to NAS.
The third opportunity facing UAS is autonomous deconfliction capacity, which is essential for the successful deployment of UAV flights in most of the envisioned application scenarios (Castillo-Effen & Visnevski, 2009). The applications of UAS in civic and military airspaces demand growing levels of human participation and oversight. This implies that UAS needs to grow in levels of autonomy in order to meet this demand. Autonomous deconfliction of UAV flights is also critical to the self-preservation of UAS and for the successful completion of its assigned missions.
Despite these numerous opportunities for the self-preservation, development, deployment, and growth of UAV in the global aviation community, there are some challenges associated with this system. One of the challenges is the achievement of autonomous deconfliction, which is critical for the successful deployment of UAV flights in commercial and military airspaces. This has proven to be a major challenge that has attracted the development of various solutions. According to Castillo-Effen & Visnevski (2009), there is a huge gap between the systematic approaches used for testing and evaluation (T&E) and autonomous deconfliction capabilities. This gap has contributed to complexities and difficulties in achieving autonomous deconfliction of this system. Consequently, UAS operators have faced challenges in maintaining separation assurance standards while deconflicting with other aircraft (Fern et al., 2011). Moreover, the challenge of autonomous deconfliction has made it difficult for UAS operators to decrease their workload when operating UAV flights.
The second major challenge facing UAS is the lack of adequate infrastructure to fully enable and support its widespread use and effective traffic management. As the number of UAS continue to increase dramatically, the need and demand for better management increases as well (UK Civil Aviation Authority, 2019). UAS traffic management remains a major issue for the global aviation community while the development and deployment of UAVs continue to rise sharply. Even though a unified or integrated approach is regarded as a suitable technique, effective UAS traffic management remains a major challenge.
Deconfliction
The successful development and deployment of UAS worldwide require autonomous deconfliction or deconfliction with other aircraft. Deconfliction is a term used to refer to the process of avoiding clear hazards or mutual interference among elements or entities within the same domain. In the aviation industry, deconfliction is essentially the process of avoiding mutual interference or clear hazards between unmanned aircraft and manned aircraft. Deconfliction in the aviation world is essential because unmanned aircraft and manned aircraft fly in the civic and military airspaces. Furthermore, deconfliction in the aviation world entails the need to recognize and lessen a loss of safe operation between and other probable sources of conflict such as weather, obstacles, and terrain. Deconfliction takes place across the full operational horizon of the operations of a UAS. The process of deconfliction of UAS can take place on two different aspects across the entire operational horizon as follows:
Strategic Deconfliction
One of the aspects of UAS deconfliction is strategic deconfliction, which is a key attribute of unmanned traffic management (UTM). Strategic deconfliction serves as the first step in deconfliction of UAS since it occurs during the pre-flight planning. Strategic deconfliction is an important function in UTM as it serves as the catalyst for safe operations of UAV flights. It entails the allocation of resources and planning access to airspace. As the number of UAV flights continues to increase, strategic deconfliction would help enhance the safe operations of UAS as it preemptively resolves conflicts.
The application of strategic deconfliction helps to preempt and resolve potential issues within and between operation plans of different airspaces. Successful deployment of UAS partially depends on effective strategic deconfliction. Prior to deployment, operational plans of different airspaces are assessed and taken into consideration. Decisions on the use of this system are based on insights obtained from consideration of these operational plans. Some of the important components that shape these decisions include geospatial factors, no-fly zones, weather and climatic conditions, airspace obstacles, and other identifiable hazards.
There have been numerous attempts in recent years to enhance the strategic deconfliction of UAS. Digital exchange of information through supporting devices is the most commonly used way for UAS operators to strategically deconflict operations. Using this approach, 4-D operation volumes that incorporate operators’ intent in a specific area are identified and used for airspace awareness (Unmanned Airspace, 2020). In addition, 4-D operation volumes are used for planning conflict-free operations that account for and avoid other operations. This approach to strategic deconfliction allows preemption, lessens human interaction, and ensures that pre-departure operations are linked to the organization and based on clear guidelines.
Tactical Deconfliction
The second approach to UAS deconfliction, which occurs during in-flight operations. According to Rios (2018), tactical deconfliction entails monitoring, conflict advisory, geographic flight containment, and alert service. Tactical deconfliction is carried out in line with strategic deconfliction to promote the successful deployment of UAS. When carrying out tactical deconfliction, operators adopt a holistic view of the airspace. Furthermore, operators maintain awareness of the state of the airspace in relation to planned and current operations. The holistic view is maintained as the UAV flight is controlled/monitored remotely. During this process, operators detect potential conflicts in the airspace early and design speedy responses for safe and efficient resolution of the identified conflicts. Operators can employ manual, automated or assisted mechanics for tactical deconfliction as part of in-flight operations. Tactical deconfliction provides live alerts and alternative flight plans in real-time (Press, 2019).
In conclusion, UAS has become significant in the global aviation community. Rapid technological advancements in recent years have facilitated increased development and deployment of UAS. While the system has primarily been used in military operations, it is increasingly developed for commercial and hobbyists marketplaces. The use of UAS in these marketplaces is attributable to its potential to transform the operations of commercial and public-sector organizations. There are many opportunities and challenges for the successful development and deployment of UAS. One of these challenges is autonomous deconfliction, which is essential to ensure the safe and efficient operations of UAS. As evident in this discussion, strategic and tactical deconfliction is essential for safe UAS operations.
References
Castillo-Effen, M. & Visnevski, N.A. (2009, March). Analysis of Autonomous Deconfliction in Unmanned Aircraft Systems for Testing and Evaluation. IEEE Aerospace Conference. DOI: 10.1109/AERO.2009.4839599
Congressional Research Service. (2016, June). Unmanned Aircraft Systems Overview – Outlook for the Domestic Drone Industry. Congressional Digest, 95(6), 2-32.
Fern, L., Flaherty, S.R., Shively, R.J. & Turpin, T.S. (2011). Airspace Deconfliction for UAS Operations. 16th International Symposium on Aviation Psychology, 451-456. Retrieved from https://corescholar.libraries.wright.edu/cgi/viewcontent.cgi?article=1077&context=isap_2011
Gambold, K.A. (2011, November). Unmanned Aircraft System Access to National Airspace. Retrieved December 7, 2020, from https://www.airpilots.org/file/917/uas-access-to-national-airspace-paper.pdf
Press. (2019, November 5). Altitude Angel Launches the Second Phase of it’s ‘Game Changing’ Conflict Resolution Service – Tactical Deconfliction. Retrieved December 7, 2020, from https://www.suasnews.com/2019/11/altitude-angel-launches-the-second-phase-of-its-game-changing-conflict-resolution-service-tactical-deconfliction/
Rios, J. (2018, July 31). Strategic Deconfliction: System Requirements. Retrieved from National Aeronautical and Space Administration website: https://utm.arc.nasa.gov/docs/2018-UTM-Strategic-Deconfliction-Final-Report.pdf
UK Civil Aviation Authority. (2019, December). A Unified Approach to the Introduction of UAS Traffic Management. Retrieved December 7, 2020, from https://publicapps.caa.co.uk/docs/33/CAP1868UTMInnovationHub.pdf
Unmanned Airspace. (2020, September 15). NASA Releases Report on Strategic Deconfliction Following Flight Tests at UAS Test Sites. UAS Traffic Management News. Retrieved December 7, 2020, from https://www.unmannedairspace.info/latest-news-and-information/nasa-releases-report-on-strategic-deconfliction-following-flight-tests-at-uas-test-sites/