The Army’s Unmanned Systems Airspace Integration Product Directorate, one of eight offices within the Unmanned Aircraft Systems (UAS) Project Office of Program Executive Office (PEO) Aviation, has conducted a successful demonstration of current Ground Based Sense and Avoid (GBSAA) capabilities at Dugway Proving Ground, UT. The June 20 demonstration was successful beyond expectations, clearing a major hurdle for testing the capability before the certification process begins. The Army will begin fielding these systems to Gray Eagle UAS training sites in early 2014.
In 2008, the Army, designated as the lead service by the Office of the Under Secretary of Defense UAS Task Force, began developing technology to allow for UAS access to the National Airspace System (NAS). The GBSAA system uses ground-based sensors (existing air traffic control and supplemental, 3-D radar) and associated technology to fuse, classify, and track air traffic for maneuver algorithms that calculate and evaluate threats, before providing the information needed to safely separate the UAS from other traffic. Many years of research and technology development have been dedicated to developing a system that provides the much-needed operational capability and has the pedigree associated with safety-critical hardware and software.
The Army first demonstrated a system in 2011 at El Mirage, CA. Development efforts were then moved to restricted airspace in Utah, which allowed a shift in focus to developing a more operationally capable system. The June 20 demonstration followed two weeks of intense testing on the system and subsystems. Specific objectives included:
• Demonstrate technology out of the laboratory in actual flight operations.
• Demonstrate the functionality and adaptability of the GBSAA system by conducting operations targeting multiple service sites.
• Highlight open-architecture, plug-and-play functionality of the GBSAA system.
• Demonstrate the ability to fuse data from 3-D and air traffic control radar (Airport Surveillance Radar-9) in real time.
• Early validation of common (cross-service) GBSAA requirements.
Seven vignettes were used to achieve the objectives. Three used live flights with unmanned systems, and four included synthetic aircraft and terrain. Sister service locations and flights against live traffic in Salt Lake City, UT, and recorded traffic from Boston, MA, were used to demonstrate the capability of the system. To show the versatility of GBSAA, two different types of radar were fused, and three different UAS—Sky Warrior-A, Hunter, and Shadow—were used for the live flights. In the third vignette, two Shadow UAS were flown toward one another. One was participating as a noncooperative aircraft and unaware of the traffic situation, while the other Shadow used the GBSAA system to recommend maneuvers to separate safely.
In every case, the GBSAA system exceeded expectations. The system proved to be capable of providing safe separation and collision avoidance to all aircraft in every vignette. Although some technology growth and improvements remain, this demonstration provided many lessons learned that can lead to advancing GBSAA technologies.
For instance, the tests enlightened users to possible human factors that will be considered when designing the GBSAA display. An example: A mathematically correct maneuver from the algorithm advises the most efficient and safe maneuver, but in some cases this may seem to contradict the mitigating actions an operator might take. In those cases, additional research will be done to explore how the algorithm can be tuned to take into account common convention without affecting the safety of the system.
The results of the GBSAA demonstration have significant implications for opening the NAS to UAS. Large numbers of unmanned aircraft are returning from overseas contingency operational support and need to continue operating and training to maintain proficiency. First responders, DoD, the U.S. Coast Guard, and U.S. Department of Homeland Security are providing critical support to the Nation at home by using unmanned systems. This system will complement those missions while ensuring that the airspace remains safe for other users.
Several years of research and development have culminated in a successful demonstration of GBSAA capabilities, leaving observers and developers excited about the way ahead. The system certification effort is underway and on track to be operational at Fort Hood, TX, in early 2014, with continued fielding to the next Gray Eagle locations. It’s an ambitious goal, but an achievable one in the hands of an ambitious GBSAA Team.
- MARY OTTMAN is Deputy Product Manager of the Unmanned Systems Airspace Integration Concepts Product Office in PEO Aviation’s UAS Program Management Office. She holds a B.S. in electrical engineering from the University of Alabama in Huntsville, an M.B.A. from Auburn University, and an M.A. in management and leadership from Webster University. She is also a graduate of the Senior Service College Fellowship program. Ottman is Level III certified in systems planning, research, development, and engineering (SPRDE) – systems engineering I, Level II certified in SPRDE – program systems engineering, and Level II certified in program management tools.