No Existing Radar Can Continuously Track a Maneuvering Hypersonic Glide Vehicle

Hypersonic glide vehicles (HGVs) like China's DF-ZF or Russia's Avangard travel at Mach 5-10 within the upper atmosphere (40-100 km altitude), below the tracking range of traditional ballistic missile defense radars that watch for objects above the atmosphere, and above the coverage of air defense radars designed for aircraft and cruise missiles at lower altitudes. This creates a persistent tracking gap. When an HGV executes an unpredictable lateral maneuver mid-flight, current radar systems lose custody of the target for seconds to minutes — an eternity when the object covers 2-3 km per second. The consequence is not merely academic. Without continuous tracking, a fire-control solution for an interceptor cannot be computed. You cannot shoot what you cannot track. The entire U.S. missile defense architecture, built over 40 years to defeat ballistic trajectories, assumes that a warhead follows a predictable parabolic path after boost phase. An HGV violates that assumption by gliding and maneuvering unpredictably for hundreds or thousands of kilometers. The radars, the algorithms, and the interceptors were all designed for a threat that flies a known curve, not one that swerves. This matters at the strategic level because it undermines deterrence. If an adversary believes they can strike a carrier group or a military base with a weapon that cannot be tracked or intercepted, the calculus of escalation changes. The defender's inability to track creates a use-it-or-lose-it pressure on high-value assets, which is destabilizing. The problem persists because radar physics imposes hard tradeoffs. Detecting a small, fast object at long range requires high power and large aperture. Tracking a maneuvering object requires rapid beam steering and short revisit times. Doing both simultaneously across a hemisphere of sky demands a sensor network of unprecedented scale. The Space Development Agency's Tracking Layer constellation of satellites is intended to fill this gap, but it won't reach initial operational capability until at least 2025-2026, and the constellation needs hundreds of satellites to provide persistent, global coverage. Structurally, the radar gap endures because the U.S. missile defense sensor architecture was designed in the 1990s-2000s against a specific threat set (North Korean and Iranian ICBMs) and optimized for that mission. Retrofitting it for HGV tracking requires not just new sensors but a new command-and-control architecture that fuses data from space-based infrared, ground-based radar, and forward-deployed sensors in real time. That integration work spans multiple combatant commands, agencies, and contractors, each with their own budgets, timelines, and institutional incentives.