Kinetic Energy Interceptor (KEI)

Quick Facts

Mobility Multi-use land/sea deployable mobile defense system
Targets Planned for all types of ballistic missiles
Role Extended coverage boost and midcourse phase missile defense.
Status Funding cancelled as of June 2009.
Producer Northrop Gruman, Raytheon (as subcontractor)

The Kinetic Energy Interceptors program’s mission is to provide the Ballistic Missile Defense System with a strategically deployable, tactically mobile land- and sea-based capability to defeat medium- to long-range ballistic missiles during the boost, ascent, and midcourse phases of flight. The Kinetic Energy Interceptor’s weapon system has the potential capacity to be deployed as an element of the Integrated Ballistic Missile Defense System in three configurations: land-mobile, sea-mobile, and land-fixed. These multiple deployment configurations increase engagement opportunities, enhance the Ballistic Missile Defense System’s layered defensive capability, and decrease life-cycle operational costs by leveraging common sub-components across the three deployed configurations.

The Kinetic Energy Interceptor weapon system is comprised of three major components: a missile launcher; a fire control and communication unit; and a high acceleration interceptor that delivers payloads capable of destroying adversary’s ballistic missiles and their lethal payloads using kinetic energy.


  • The Kinetic Energy Interceptors destroy ballistic missiles in the boost, ascent, or midcourse phases of flight.
  • During the boost or ascent phase intercepts, the interceptor’s payload acquires, homes, and kinetically destroys a boosting ballistic missile prior to deployment of its lethal payload, decoys, and countermeasures.
  • For midcourse phase intercepts, the interceptor acquires data and discriminates the incoming missile’s lethal payload from accompanying decoys, countermeasures and exhausted boost motors; then autonomously homes in and kinetically destroys the lethal payload.
  • The Kinetic Energy Interceptor system mobility enables rapid deployment near adversary’s launch sites and subsequent early battle-space engagements of the adversary’s ballistic missile in the boost, ascent, and early midcourse phases of flight.
  • Mobility provides the operational flexibility to respond to changing adversary conditions (countries, countermeasures, and tactics) and mitigates an adversary’s capability to exploit our fixed-site ballistic missile defense weapon systems.
  • The Kinetic Energy Interceptor fire control component interfaces with the Ballistic Missile Defense System Command and Control element, Ballistic Missile Defense System sensors and other overhead sensors to obtain threat tracking data.


The program was terminated due to the fiscal and technological issues in May 2009.