Anti-Missile System Scores Test Hit

Article excerpt

The Pentagon's strategic ballistic missile defense intercepted a test target Sept. 1 for the first time since President George W. Bush ordered the rudimentary system deployed nearly four years ago. The success comes on the cuspof a U.S. decision to extend the system to Europe, although nongovernmental missile defense proponents vigorously advocate a different destination: space.

Just hours after the test, Lieutenant General Henry Obering, director of the Pentagon's Missile Defense Agency (MDA), declared the experiment a "total success" and a "huge step" for advancing missile defenses. He also said the outcome gave him confidence that the system had a "good chance" of destroying a missile in a real attack. Nonetheless, the flight test fell short of resembling a realistic scenario, and in one respect, it was less difficult than past tests.

Still, the experiment involved several firsts. It involved the first launch of an interceptor of the same make as the 11 currently deployed at Fort Greely, Alaska, and the two stationed at Vandenberg Air Force Base, California. In another departure, both the test interceptor and target missile were launched from new locations.

The test interceptor was launched from Vandenberg. Prior testing involved firing the interceptor from Kwajalein Atoll in the Marshall Islands. The target missile was launched from Kodiak, Alaska, rather than Vandenberg in order to generate a different trajectory.

Instead of shooting the target missile west over the Pacific Ocean toward Hawaii, the new launch point enabled MDA to fire the target south. That allowed the target missile's flight to more closely resemble the path that a North Korean missile might take. For some time, the Pentagon has postulated that North Korea represents one of the key near-term threats that the rudimentary defense must be prepared to stop. That premise only appears to have been reinforced after Pyongyang in July conducted a partly successful spate of missile tests, even though the longest-range system failed shortly after takeoff. (See ACT, September 2006.)

In the Sept. 1 flight test, an early-warning satellite detected the target missile's launch and relayed coordinates to the ground-based mid-course (GMD) system's fire control center at Colorado Springs, which cued an early-warning radar located at Beale Air Force Base, California, to start tracking the target. Once the radar started tracking the missile, trajectory data was sent back to Colorado Springs, where a "firing solution" was formulated and then electronically fed into the test interceptor at Vandenberg.

The interceptor blasted out of its silo roughly 16 minutes after the target's launch. After the interceptor's final booster rocket burned out, it released an exoatmospheric kill vehicle (EKV) in space. This roughly 60-kilogram mass of sensors then received a target update from Colorado Springs and maneuvered into a collision with the mock warhead from the target missile. The collision occurred approximately six and one-half minutes after the interceptor's launch.

"What we saw today was a very realistic trajectory for the threat.. .and a wry realistic trajectory, a very realistic intercept altitude, and intercept speeds for the.. .interceptor against the target," Obering told reporters afterward. In addition, the system's fire control center was manned by an actual crew of the 100th Missile Defense Brigade, instead of private contractors. Obering concluded that "this is about as dose as we can come to an end-to-end test of our long-range missile defense system."

Still, key elements of the system did not participate in the test Although tested separately on other occasions, the Cobra Dane radar located at the western tip of the Aleutian Islands could not be used because it is permanently oriented away from the recent experiment's location. Cobra Dane would be the primary radar for relaying early tracking data on a missile fired at the United States from the direction of Asia. …