Airborne Boost-Phase Ballistic Missile Defense

Boost-phase ballistic missile defense is alluring because rocket boosters are easy to detect and track, they are relatively vulnerable due to the large axial loads on a missile under powered flight, the entire payload (single or multiple warheads and midcourse penetration aids) may be destroyed in a single shot, and countermeasures to defeat boostphase defense are more difficult to devise than for midcourse ballistic missile defenses. Moreover, if intercepted several seconds before booster burnout, the debris will land well short of the target area, although collateral damage to other territory is a serious concern. On the other hand, boost-phase ballistic missile defense is technically challenging because the intercept timelines are very short (1–3 minutes for theater-range ballistic missiles and 3–5 minutes for intercontinental range missiles) and missile boosters are accelerating targets, thus complicating the design of homing kinetic-kill vehicles (KKVs). This article examines the technical feasibility and nominal capability of one type of boost-phase defense, namely, airborne boost-phase intercept (ABI). Airborne laser systems are not examined here.1 This article concludes that ABI should be technically achievable within the next decade and that airborne platforms offer some unique advantages, especially for theater ballistic missile defense, that warrant their serious consideration in future U.S. missile defense architectures.