; and (2) the test ranges (as defined in section 44801 of title 49, United States Code) should continue to be leveraged for research on— (A) air traffic management systems for unmanned aircraft systems; and (B) the integration of such systems into the national airspace system. 405. 21st Century Aeronautics Capabilities Initiative (a) In general The Administrator may establish an initiative, to be known as the 21st Century Aeronautics Capabilities Initiative , within the Construction and Environmental Compliance and Restoration Account, to ensure that NASA possesses the infrastructure and capabilities necessary to conduct proposed flight demonstration projects across the range of NASA aeronautics interests. (b) Activities In carrying out the 21st Century Aeronautics Capabilities Initiative, the Administrator may carry out the following activities: (1) Any investments the Administrator considers necessary to upgrade and create facilities for civil and national security aeronautics research to support advancements in— (A) long-term foundational science and technology; (B) advanced aircraft systems; (C) air traffic management systems; (D) fuel efficiency; (E) electric propulsion technologies; (F) system-wide safety assurance; (G) autonomous aviation; and (H) supersonic and hypersonic aircraft design and development. (2) Any measures the Administrator considers necessary to support flight testing activities, including— (A) continuous refinement and development of free-flight test techniques and methodologies; (B) upgrades and improvements to real-time tracking and data acquisition