Japan to Develop Interception System for North Korea’s Irregular-trajectory Missiles

Amidst rising threats from North Korean ballistic missiles, Japan’s Defense Agency has begun deliberations on the development of a new missile interception system.

Research will begin in 2020 on improving the Ground Self-Defense Force’s Type-03 medium-range surface-to-air missile (Chu-SAM) by adding ballistic missile interception capability. The agency aims to be capable of responding to a new type of missile being developed by North Korea that flies on an irregular trajectory.

Multiple government officials revealed the new development on December 28, 2019. Once completed, the new system would strengthen Japan’s air self-defense as the “third line” of defense, after the SM-3 interceptor missile launched by the Maritime Self-Defense Force’s Aegis cruiser and the Air Self-Defense Force’s surface-to-air Patriot missile system (PAC3).

The Chu-SAM missile system was developed domestically. Deployments of an upgraded version, which significantly extends the missile’s 100-kilometer range, are to begin in Japan Ground Self-Defense Force (JGSDF) units in late 2020. Although the Chu-SAM can shoot down enemy fighter aircraft and cruise missiles, it cannot currently defend against ballistic missiles. Thus, the Defense Agency is advancing improvements to create an upgraded version of the Chu-SAM, making it capable of intercepting ballistic missiles just before impact.

Specifically, the Defense Agency has begun working to verify technology that will enable the system to defend against ballistic missiles — including new types — by making improvements to the guided projectile (the anti-ballistic missile itself) and the fire control system. The improvements would enhance the system’s capacity to predict the trajectory of enemy ballistic missiles.

The improved Chu-SAM would also serve to fill in the gap left by the PAC3, which has an interception range of only 70 kilometers (about 43.5 miles). Development is expected to take about three years.

The presumed target of these improvements is the new short-range ballistic missile with an irregular trajectory developed by North Korea in 2019, based on the Russian Iskander missile. This missile flies a complex trajectory that differs from conventional missiles, flying in at low altitude and rising again prior to impact.

This new North Korean missile has become a major national security concern as the existing SM-3 system responds only to high-altitude targets and cannot intercept it. The PAC3 missile defense system also has difficulty coping with the irregular trajectory.

China and Russia are also developing a “hypersonic glide missile.” This missile is reputed to fly at hypersonic speed (over Mach 5), has a complex trajectory, and will be able to break through present-day missile defense networks. For this reason, plans are also in place to further enhance the sophistication of the Chu-SAM over a seven-year project by adding high-output radar than can detect enemy missiles, building upon the upgraded Chu-SAM system.

The Japanese government has designated the rapid improvement of ballistic missile technology by North Korea as a “new threat.” Minister of Defense Taro Kono also has emphasized the need to “enhance comprehensive missile defense capabilities.”

Competition to improve missile attack and defense technology could easily become a game of cat-and-mouse. For this reason, “sight” capabilities are considered key. The U.S. is developing technology to fly drones near enemy launch sites to detect signs of launch. It is also crucial to create a system for high-precision detecting and tracking of enemy missile launches based on collaborated operation of multiple artificial satellites.

(Click here to read the article in Japanese.)

Author: Issei Tanaka, The Sankei Shimbun