Hypersonic Weapons: DOD Should Clarify Roles and Responsibilities to Ensure Coordination Across Development Efforts, Report to Congressional Addressees [open pdf - 3MB]
From the Highlights: "Hypersonic missiles, which are an important part of building hypersonic weapon systems, move at least five times the speed of sound, have unpredictable flight paths, and are expected to be capable of evading today's defensive systems. DOD has begun multiple efforts to develop offensive hypersonic weapons as well as technologies to improve its ability to track and defend against them. NASA and DOE [Department of Energy] are also conducting research into hypersonic technologies. The investments for these efforts are significant. This report identifies: (1) U.S. government efforts to develop hypersonic systems that are underway and their costs, (2) challenges these efforts face and what is being done to address them, and (3) the extent to which the U.S. government is effectively coordinating these efforts. This is a public version of a sensitive report that GAO [Government Accountability Office] issued in January 2021. Information that DOD deemed to be sensitive has been omitted. GAO collected and reviewed information from DOD, DOE, and NASA to identify hypersonic weapons development efforts from fiscal years 2015 through 2024. GAO also analyzed agency documentation and interviewed agency officials."
Government Accountability Office: https://www.gao.gov/