|Mobility||Sea- and land-based|
|Targets||Short-, intermediate-range ballistic missiles; satellite interception capable|
|Role||Area, eventually all phases of missile defense|
|Components||Shipboard SPY-1 radar
Command and control systems
The Standard Missile-3 (SM-3) is a derivative of the RIM-156 Standard SM-2 Block IV missile, and is the interceptor component of the U.S. Navy theater ballistic missile defense system, called NTW-TBMD (Navy Theater Wide – Theater Ballistic Missile Defense). It is an upper-tier (exo-atmospheric) ballistic missile defense weapon designed to intercept short- to intermediate-range ballistic missiles in the midcourse and terminal phases of flight. The SM-3 was originally planned to complement the lower-tier SM-2 Block IVA until the latter was canceled in December 2001. However, modern Aegis software has allowed the SM-3 to work in cooperation with lower-tier SM-2 and SM-6 air defense missiles.
The SM-3 missile, designated RIM-161A, uses the basic SM-2 Block IVA airframe and propulsion, and adds a third stage rocket motor (a.k.a. Advanced Solid Axial Stage, ASAS, made by Alliant Techsystems), a GPS/INS guidance section (a.k.a. GAINS, GPS-Aided Inertial Navigation System), and a LEAP (Lightweight Exo-Atmospheric Projectile) kinetic warhead (a non-explosive hit-to-kill warhead). The SM-3 interceptor replaced the SM-2’s explosive warhead and radar seeker with an additional solid-fueled third-stage motor and infrared homing kinetic kill vehicle, otherwise known as a LEAP.
The LEAP uses a Forward Looking Infrared (FLIR) sensor to locate its target, and was tested in 4-flight series called Terrier/LEAP from 1992 to 1995. These tests used modified Terrier and Standard Missile-2 missiles. Two intercepts were attempted during these tests, but the LEAP failed to hit the target in both cases. The first flight-test of an RIM-161A SM-3 missile occurred in September 1999, and the third test (in January 2001) demonstrated successful missile flight and control up to fourth stage (i.e. kinetic warhead) separation. In January 2002, the first all-up test of an SM-3 succeeded in intercepting an Aries ballistic target missile. For up-to-date information on testing, see the “U.S. Missile Defense Intercept Test Record” section of our web site. SM-3 has successfully achieved 28 out of 36 intercepts during tests including the satellite shoot down in February 2008.
The European Phased Adaptive Approach (EPAA)
Aegis BMD and the SM-3 make up the foundation of the EPAA. Each phase of the EPAA calls for the deployment of upgraded SM-3 variants to counter the improving ballistic missile capabilities of Iran. In March 2011, Phase I of the EPAA mandated the deployment of 113 SM-3 Block IA interceptors and 16 SM-3 Block IB interceptors to Aegis BMD ships in Europe.
In 2015, Phase II called for 100 SM-3 Block IB interceptors to be deployed in Europe alongside the new Aegis Ashore site in Romania. The new land-based version—Aegis Ashore—is configured as Aegis BMD 5.0 with SM-3 IB interceptors. Aegis BMD 5.0 does not add new functionality, but is designed to integrate Aegis BMD 4.0.1 with the Navy’s open architecture system, enabling any Aegis ship to perform the BMD mission.
Scheduled for 2020, the third phase of the EPAA mandates the deployment of 19 new SM-3 Block IIA interceptors alongside the development of another Aegis Ashore site Poland. Phase IV of the EPAA originally called for the deployment of SM-3 Block IIB interceptors capable of intercepting ICBMs coming out of Iran. However, diplomatic pressure from Russia resulted in the cancelation of the fourth phase of the EPAA and development of the SM-3 Block IIB halted.
The Department of Defense shifted in strategy for the defense of Europe from one that relied on Ground-Based Midcourse Defense interceptors in Poland, to implementing the new European Phased Adaptive Approach (EPAA) in which Aegis BMD became the centerpiece. The currently deployed systems for Phase I and II of the EPAA are Aegis BMD 3.6.1, 4.0.1, and 5.0 with SM-3 Block IA and IB interceptors. Phase III of the EPAA calls for the development, testing, and deployment of new SM-3 Block IIA interceptors and Aegis BMD 5.1 systems to Europe by 2018.
To meet the mandates set by Phase III of the EPAA, the U.S. Navy, in cooperation with Japan, is currently developing and testing the SM-3 Block IIA interceptor. This interceptor has a greater range and higher velocity to intercept fast-moving intermediate-range ballistic missiles more effectively. In June 2015, the Block IIA was first flight tested and the interceptor successfully demonstrated flyout through nosecone deployment and third stage flight. In December of that year, the SM-3 Block IIA again underwent a flight test and successfully demonstrated flyout through kinetic warhead ejection. Following the two successful flight tests, the SM-3 Block IIA conducted a successful test intercept on February 4, 2017, however, the upgraded interceptor failed to successfully intercept a target missile during a scheduled intercept test on June 22, 2017. The SM-3 Block IIA will continue being tested until its scheduled deployment in 2020, at which time it is expected that Aegis BMD 5.1 will employ the Block IIA interceptors on both ships and at the Aegis Ashore site in Poland.