A simulated ballistic missile in the boost phase of flight was intercepted in a test conducted at the White Sands Missile Range in New Mexico Dec. 3. After a troubled test in September, a Network Centric Airborne Defense Element (NCADE) seeker — mounted on an AIM-9X Sidewinder airframe — destroyed a target sounding rocket in boost phase for the first time. The test is noteworthy not only for success, but for the established systems NCADE leverages. Boost-Phase Intercept Ballistic missile defense (BMD) is divided into three basic phases of intercept: boost, midcourse and terminal. Before NCADE, technologies to intercept ballistic missiles in the boost phase of flight were slow to mature — a phenomenon with roots in both historical and technological issues. Boost-phase intercept requires relatively close access to territory or airspace adjacent to missile launch sites (compared to midcourse- or terminal-phase intercepts, which must be further back).