Aeronautics Innovation Act This bill reauthorizes through FY2023 the National Aeronautics and Space Administration (NASA) Aeronautics Research Mission Directorate. The bill expresses the sense of Congress that developing high-risk, precompetitive aerospace technologies for which there is not yet a profit rationale is a fundamental NASA role and states that it is U.S. policy to maintain world leadership in military and civilian aeronautical science and technology, global air power projection, and industrial leadership. NASA shall: ensure continuing support for the Aeronautics Strategic Implementation Plan to support the future needs of aviation communities, establish a national policy for aeronautics research to maintain U.S. superiority in air capabilities and aviation industrial leadership, establish a low-boom supersonic aircraft program to demonstrate supersonic aircraft designs and technologies to reduce sonic boom noise levels, establish a new series of experimental planes (X-planes) to demonstrate aircraft vehicle and propulsion concepts and technologies, continue support of unmanned aircraft (drone) system development, and establish the 21st Century Aeronautics Capabilities Initiative to ensure that it possesses the infrastructure capabilities and tools necessary to conduct flight demonstration projects across the range of NASA aeronautics interests.