The Japan Maritime Self Defense Force’s (JMSDF) two improved Atago-class (aka 27DD- or 27DDG-class) guided missile destroyers will reportedly be fitted with supersonic Standard Missile 6 (SM-6) air defense missiles, a Japanese Ministry of Defense (MoD) spokesperson told IHS Jane’s on September 3.
The decision follows the publication of the Japanese MoDs 2019 defense budget request last week, which asks for $99.9 million for the procurement of an undisclosed number of SM-6 missiles. Earlier this year, the MoD had reportedly decided against procuring SM-6s for budgetary reasons.
The vertically-launched SM-6 was originally designed for anti-air warfare and anti-surface warfare. In 2015, the missile — designated Standard Missile-6 Dual 1 — was modified for sea-based terminal ballistic missile defense with the capability of intercepting a ballistic missile warhead descending from the upper atmosphere at great speed.
In 2016, an SM-6 sank the Oliver Hazard-Perry-class guided-missile frigate USS Reuben James during a test.
Along with the soon to be operationalized Standard Missile-3 Block (SM-3) IIA, capable of intercepting ballistic missiles midcourse, the SM-6 will significantly boost the improved Atago-class’ missile defense capabilities.
The first of two planned improved 8,200-ton Atago-class guided missile destroyers was launched in late July. The lead ship, christened Maya (PN 179), is expected to be operationally deployed by the JMSDF by 2021.
It is the seventh JMSDF surface warship to be equipped with the Aegis combat system. In detail, the warship will be fitted with the Aegis Baseline J7 combat system, the Japanese equivalent to the U.S. Navy’s Baseline 9/BMD 5.1 standard Aegis combat system.
In February, the United States and Japan successfully tested the Aegis Baseline 9/BMD combat system with an SM-3 Block IIA missile that successfully destroyed an incoming ballistic missile target in midcourse. To date, the SM-3 Block IIA, which has been under joint development by U.S. defense contractor Raytheon and Japan’s Mitsubishi Heavy Industries since 2006, has not been declared operational.
An additional test of the Aegis Baseline 9 combat system was conducted in August 2017 and involved an SM-6 intercepting a medium-range ballistic missile target at sea in its terminal flight phase. The test was conducted to verify a new targeting software for the SM-6 for intercepting ballistic missiles.
“Next to the SM-3 (…) the new improved Atago-class will carry the RIM-66 Standard Missile-2 (SM-2) surface-to-air missiles and the RIM-162 Evolved Sea Sparrow Missile (ESSM),” I explained in July. “All these missiles can be fired from the Maya’s 96 Mk 41 vertical launch system cells.”
Notably, the improved Atago-class will also be fitted with the so-called cooperative engagement capability (CEC), “a new wide-area integrated air defense system, which permits the real-time sharing of sensor data on air targets, including incoming enemy aircraft and cruise missiles, among CEC-equipped ships,” as I explained elsewhere.