Advancing the Upper Class E Traffic Management (ETM) Concept: Results of NASA’s First ETM Collaborative Evaluation with Industry Partners

Innovative aircraft design and emerging technologies are enabling new types of uncrewed, high-altitude long endurance (HALE) vehicles, including fixed-wing HALE vehicles and stratospheric balloons to operate above 60,000 feet. However, due to a variety of factors including the diverse performance characteristics and extended mission duration of these new vehicles, the Air Traffic Management system faces challenges in meeting the needs of this high-altitude environment. To address these challenges, the Higher Airspace (HA) / Upper Class E Traffic Management (ETM) concept proposes using a scalable, cooperative approach tailored for high-altitude operations. To evaluate the feasibility of the HA/ETM concept, NASA Ames Research Center conducted the first Collaborative Evaluation (CE-1) in partnership with two HALE vehicle operators, Aerostar and AeroVironment. The CE-1 activity included: 1) A connectivity demonstration enabling the remote partners to exchange operational intent data with NASA’s ETM Service Supplier (ESS), and 2) A flight simulation involving four simultaneous operations to assess whether the cooperative ETM approach could safely increase airspace capacity as compared to the current Altitude Reservation (ALTRV) method. Results showed that operational intent was successfully exchanged with the NASA ESS and that the ETM concept allowed four vehicles to safely share a 40 x 40 nautical mile area – as compared to only one vehicle under the traditional ALTRV process – for all scenarios, including the ones in which the vehicles had to resolve strategic conflicts between their operational intents. Building on CE-1's success, the next evaluation is planned to further the HA/ETM concept development by exploring scenarios with more dynamic intent submissions and open-ended conflict negotiation strategies.