SM-2 RIM-66 / RIM-67 Standard Missile
In response to the changing threat, the US Navy funded the development of today's Standard
Missile-2 (SM-2). Standard-2 MR incorporates midcourse guidance, which allows programming of the missile for radar search only. The missile is redirected in midflight and then again during the terminal homing phase. SM-2 MR is installed on the DDG- and CGN-type ships and on Aegis CG-class ships.
SM-2 is deployed in several different configurations, ranging from the SM-2 Block IIIA up through the SM-2 Block IV ER for the US Navy's AEGIS compatible ships. SM-2's primary role is to provide area defense against enemy aircraft and antiship missiles. The current generation of SM-2 Blocks IIIA and IIIB, capitalizes on technology improvements to substantially increase performance against the advanced antiship missile threat.
The Standard Missile-2 (SM-2) is the Navy's primary surface-to-air fleet defense weapon. The currently deployed SM-2 Block II/III/IIIA configurations are all-weather, ship-launched medium-range fleet air defense missiles derived from the SM-1 (RIM-66B). SM-2 employs an electronic countermeasures-resistant monopulse receiver for semi-active radar terminal guidance and inertial
midcourse guidance capable of receiving midcourse command updates from the shipboard fire control system. SM-2 is launched from the Mk 41 Vertical Launching System (VLS) and the Mk 26 Guided Missile Launching System (GMLS). SM-2 continues to evolve to counter expanding threat capabilities, and improvements in advanced high and low-altitude threat interception, particularly in stressing electronic countermeasures (ECM) environments, are being implemented through modular changes to the missile sections.
The SM-2 is a solid propellant-fueled, tail-controlled, surface to air missile fired by surface ships. Designed to counter high-speed, high-altitude anti-ship cruise missiles (ASCMs) in an advanced ECM environment, its primary mode of target engagement uses mid-course guidance with radar illumination of the target by the ship for missile homing during the terminal phase. The SM-2 can also be used against surface targets. SM-2 Blocks II through IV are long-range interceptors that provide protection against aircraft and antiship missiles, thereby expanding the battlespace.
The Block II version of SM-2 includes a signal processor to provide less vulnerability to ECM, an improved fuze and focused-blast fragment warhead to provide better kill probability against smaller, harder targets, and new propulsion
for higher velocities and maneuverability.
A Block III version of SM-2 provides improved capability against low altitude targets.
Block IIIA, a modification to this version, extends capability to even lower altitudes. RIM-66C Block IIIA includes a new warhead that imparts greater velocity to warhead fragments in the direction of the target.
Block IIIB is the next step in the continuing evolution of the Standard Missile family, incorporating an infrared (IR) guidance mode capability developed in Missile Homing Improvement Program (MHIP) with the radio frequency (RF) semi-active guidance system of the proven SM-2 Block IIIA. The MHIP dual-mode RF/IR guidance capability is being incorporated to counter a specific fielded and proliferating electronic warfare systems in existing aircraft and ASCM threats. OPEVAL of SM-2 Block IIIB was conducted during April 1996, with missile firings by an Aegis cruiser that was completing workup training for deployment. Based on OPEVAL results, SM-2 Block IIIB is operationally effective and suitable.
Block IIIC The centerpiece of the unfunded [as of 2009] SM-2 Block IIIC is a steering control upgrade-derived from the SM-6-the addition of jet-tab thrust vector control, improved guidance system and different autopilot. The thrust vector control is primarily aimed at enhancing short-range performance. As a second step, the Navy and Raytheon are considering a dual-pulse rocket motor enhancement and introduction of more advanced guidance software. The upgrade program has attracted international interest - the SM-2 has a broad customer base, and many countries operating Block IIIAs would like to modernize them.
These SM-2 versions are provided as medium range (MR) rounds that can be fired from Aegis rail launchers, Aegis vertical launch systems (VLS), and Tartar rail launchers.
The Block IV version was developed to provide extended range [ER], improved cross-range and higher altitude capability for Aegis VLS ships, as well as improved performance against low RCS targets and against complex ECM. The SM-2 Block IV is a kinematic improvement beyond the SM-2 Block III, incorporating a thrust-vector controlled booster, a more robust airframe, and guidance and control modifications for improved altitude/range/cross-range coverage against high-performance, low radar cross-section threats in a stressing electronic countermeasures (ECM) environment. Standard-2 ER incorporates the same midcourse guidance as the MR version.
RIM-67E was an interim designation of the SM-2ER Block IV. The Navy initially proposed the designation RIM-68A for the Block IV missile, in sequence with the RIM-66 and RIM-67. However, the designation RIM-156A was allocated instead.
The Standard Missile-2 Block IV program experienced considerable development problems and schedule delays in 1991. Primarily due to booster problems, the first successful propulsion test vehicle firing was been delayed more than a year. As a result, the initial production decision, once scheduled for the middle of fiscal year 1991, slipped until December 1992, the first quarter of fiscal year 1993. Since only early IOT&E of SM-2 Block IV was conducted to support its LRIP decision, its capability was never fully determined (capability was not demonstrated against ASCM threat representative, maneuvering targets nor against low altitude, low Doppler targets). That is, the Block IV program was restructured, with the intention to proceed to DT&E/OT&E to support a full production decision if technical problems are encountered with development of the SM-2 Block IVA that preclude its retention of Block IV capability (never fully determined) against anti-air warfare threats.
In addition to providing significant increases in ship area defense capability, the SM-2 Block IV is the developmental stepping stone to SM-2 Block IVA, the Navy's Area Theater Ballistic Missile Defense (TBMD) missile.
Block IVA adds a dual-mode radio frequency/infrared (RF/IR) sensor, an upgraded ordnance package, and autopilot/control enhancements to the SM-2 Block IV The SM-2 Block IVA missile uses the TBMD-modified Aegis Weapon System on board Aegis cruisers and destroyers to track and engage TBMs, enhancing U.S. littoral warfare capability by allowing Aegis ships to provide TBMD for ships at sea and ground force embarkation areas ashore, without the constraints imposed by sealift or airlift. The SM-2 Block IVA upgrade is being developed to provide capability against theater ballistic missiles, although it is planned to retain capability against anti-air warfare threats. A System Design Review for SM-2 Block IVA was conducted in December 1993 and a Risk Reduction Flight Demonstration (RRFD) program was initiated in FY 1994. An Environmental Test Round (ETR-2A) was successfully launched in the summer 1996. On January 24, 1997, the Navy successfully demonstrated a Theater Ballistic Missile Defense capability when a ballistic missile target was shot from the sky for the first time using a new version of the Standard missile family. This Developmental Test Round (DTR-1) demonstrated the imaging infrared seeker and the capability to intercept a TBM.
Full production approvals for SM-2 Blocks have been as follows: Block II was approved in December 1986; Block III in June 1988; Block IIIA in February 1992; and Block IIIB in September 1996, following the OPEVAL summarized below. Block IV was approved for LRIP in May 1995, but further development and procurement were deferred, depending on development of the Block IVA missile, the interceptor for the Navy Area TBMD program, and Block IVA retention of Block IV capability against anti-air warfare threats. On April 16, 1999 Raytheon Systems Company, Tucson AZ, was awarded a not-to-exceed $135,236,224 fixed-price with award-fee, letter contract for the procurement of 71 SM-2 Block IIIB (AUR's), 63 SM-2 Block IIIB ORDALT kits to upgrade SM-2 Block III missiles to SM-2 Block IIIB, 43 SM-2 Block IV AUR's, 100 AN/DKT-71A telemetric data transmitting sets, section level spares, shipping containers and handling equipment.
Join the GlobalSecurity.org mailing list