On May 16, at the Pacific Missile Range Facility in Hawaii, a Raytheon SM-3 Block IB hit-to-kill interceptor was successfully fired by the Aegis-equipped cruiser U.S.S. Lake Erie at a separating short-range ballistic missile target. The FTM-19 test was not only the 23rd successful intercept for the SM-3 weapon, but the third consecutive success for the latest Block IB version. Having achieved three successful strikes in a row, the Block IB is now authorized for production.
“FTM-19 marked a transition from scripted development tests into the operational test phase,” remarked Wes Kremer, v-p Raytheon air and missile defense systems. “It was performed by an operational ship with an operational crew, and they were given no notice of when the target would be launched. For us it was a big step, as it answered the requirements for initial production decisions to be taken.” In the fall of 2012 Raytheon was authorized to begin procurement of long-lead items for the Block IB, especially the items that are common with the Block IA, but now it can begin assembly of the new missile version.
SM-3 Block IB is slated to be deployed from 2015 as part of Phase II of the U.S. Phased Adaptive Approach (PAA) to missile defense in Europe. The first phase of PAA, employing the current production SM-3 Block IA standard, is already operational with the U.S. Navy’s Aegis vessels in the Mediterranean. Under Phase II, land-based SM-3 Block IB missiles will be deployed in Romania. It is likely that the first operational weapons will be the residue from the 33 development rounds that are already under contract.
SM-3 interceptors can be cued by a variety of sources. To date the primary sensor has been the SPY-1 radar carried by Aegis vessels but, in April 2011 (FTM-15), Raytheon demonstrated a launch-on-remote capability of an SM-3 cued by a TPY-2 radar. More recently, in February’s FTM-20 test, an SM-3 Block IA was cued by Raytheon sensors aboard the STSS-D (space tracking and surveillance system-demonstrator) satellite.
Block IB SM-3s retain the first- and second-stage rocket stack used by the Block IA, but important changes are introduced to the third-stage kill vehicle. It has a new two-color, 256- by 256-pixel imaging infrared seeker in place of the earlier single-band seeker, providing better discrimination against more complex threats. It also introduces the TDACS (throttleable divert and attitude control system), an advanced vehicle guidance rocket system that uses proportional guidance rather than the “bang-bang” style of on-off guidance previously employed. The greater capabilities of these two systems have combined to require a new signal processor.
Next-generation Interceptor
Raytheon is now working with Mitsubishi in Japan to develop the SM-3 Block IIA missile that will be deployed with Phase III of the PAA. The Japanese Self Defense Force, which already employs SM-3 Block IAs, is likely to adopt the weapon, and is also looking at the Block IB.
Mitsubishi has responsibility for developing a new propulsion stack with an increased diameter of 21 inches for greater reach. Raytheon, meanwhile, is focusing on the third-stage kill vehicle that will have a larger focal plane array seeker of 512-by-512 pixels. The larger size of the interceptor, and its improved seeker, greatly expand its engagement envelope. Currently around two thirds of the subassembly critical design reviews have been completed, with a full-system CDR scheduled for around September this year.
Initial trials of Block IIA ground test vehicles are scheduled to begin late next year, primarily to test separation. A new canister has been designed to accommodate the heavier missile. In 2015 whole missiles are due for launch testing, but without a target. Two guided trials against targets have been contracted for, to be undertaken in 2016. In terms of the PAA, the Block IIB interceptor is due for deployment in Poland from 2018, to be employed alongside Block IB missiles. The fourth and final phase of PAA, ostensibly to be deployed from 2020, is under discussion and may lead to a US-based system with a yet-to-be-defined SM-3 Block IIB interceptor with advanced kill vehicle.
In the meantime, Raytheon is presenting its SM-3 family as a potential candidate to fulfill ballistic missile defense requirements, notably in Europe. “SM-3 is certainly the most proven upper-tier missile defense in the world,” Kremer told AIN. “We believe there are many opportunities around the world to augment what many countries already operate. These are mostly terminal in their nature, like the Patriot.”
It has been reported that Raytheon has been in discussion with a number of nations, such as Denmark, Germany and The Netherlands, concerning the possibility of adding an SM-3 based ballistic missile defense capability through adaptations of existing vessels, even though they are not equipped with the Aegis system.
