No Existing Sensor Can Reliably Track Maneuvering Hypersonic Missiles

Hypersonic weapons -- missiles traveling above Mach 5 that can maneuver throughout their flight -- present thermal signatures 10 to 20 times fainter than traditional ballistic missiles, rendering current U.S. geostationary satellite-based detection systems largely ineffective. Unlike ballistic missiles that follow predictable parabolic trajectories after boost phase, hypersonic glide vehicles maintain powered, maneuverable flight at altitudes below the detection threshold of most terrestrial radars, leaving defenders with minutes or even seconds of warning rather than the 20-30 minutes provided by traditional ICBM detection. This matters because the entire U.S. missile defense architecture was built around the assumption that incoming threats follow ballistic trajectories. Ground-based radars, space-based infrared satellites, and command-and-control systems all rely on predicting where a missile will be based on its boost-phase trajectory. Hypersonic weapons break this assumption entirely. They compress decision timelines from hours to minutes, meaning that by the time a hypersonic threat is detected, there may be insufficient time to observe, orient, decide, and act -- the fundamental OODA loop that military commanders depend on. A successful hypersonic strike against a carrier group, forward base, or command node could be accomplished before any defensive response is possible. China has deployed the DF-ZF hypersonic glide vehicle and tested the DF-17 medium-range system. Russia has fielded the Avangard hypersonic glide vehicle on its ICBMs and deployed the Kinzhal air-launched hypersonic missile in combat in Ukraine. North Korea has tested its own hypersonic prototypes. The proliferation is accelerating while the defensive gap remains open. The structural reason this problem persists is that detecting and tracking hypersonic weapons requires a fundamentally different sensor architecture -- a proliferated constellation of satellites in low Earth orbit rather than a small number of exquisite satellites in geostationary orbit. The Hypersonic and Ballistic Tracking Space Sensor (HBTSS) program and the Space Development Agency's Tracking Layer are being developed to fill this gap, but fielding a full operational constellation requires launching hundreds of satellites, integrating them with existing command infrastructure, and developing fire-control-quality tracking data -- a process that will take years and billions of dollars. Until this new sensing architecture is operational, the U.S. faces a window of vulnerability where adversary hypersonic weapons can potentially penetrate existing defenses. A March 2025 MDA and Navy test demonstrated that HBTSS data could detect and track a maneuvering hypersonic target in a simulated engagement, but moving from a successful test to a deployed, reliable, global tracking capability is a multi-year journey that adversaries are racing to exploit.