WASHINGTON — A test of the U.S. territorial missile defense system ended in failure because the sea-based cuing radar for the interceptor did not perform as planned, the U.S. Missile Defense Agency (MDA) announced Jan. 31.

The Jan. 31 test was the first of the Ground-based Midcourse Defense (GMD) system in which the Sea-Based X-band radar was the primary source of tracking and targeting information, MDA spokesman Rick Lehner said Feb. 1. “It was the only radar used in the test,” he said.

Previous tests of the GMD system have relied primarily on other radar tracking assets, such as the very high frequency radar at Beale Air Force Base in California. Lehner said the X-band radar is a more precise cuing tool for missile interceptors.

Both the target missile and the GMD interceptor performed as intended after launch, the MDA said.

Lehner was unable to say at what point during the test the Sea-Based X-band radar failed. The ocean-going radar, built by Raytheon Co. under subcontract to GMD prime contractor Boeing Co., was in the South Pacific Ocean west of Hawaii for the test. The radar dome rests on a modified, self-propelled oil-drilling platform. The target missile was launched from the U.S. Army’s Reagan Test Site on the Kwajalein Atoll in the Pacific, and the GMD interceptor took off from Vandenberg Air Force Base, Calif. The intercept was supposed to have occurred high in the sky somewhere above the vicinity of the radar, Lehner said.

In addition to being the first to rely on the Sea-Based X-band radar for cuing data, the Jan. 31 test was the first in which the target was launched from Kwajalein, Lehner said. In addition, the GMD interceptor was topped with an advanced version of the Raytheon-built Exoatmospheric Kill Vehicle that was flying for the first time, he said.

Lehner said the marginal cost of a GMD intercept test typically runs between $120 million and $125 million, which includes test preparations, data analysis and the hardware.

The MDA is establishing a failure review board to investigate what went wrong. It likely will be weeks before the initial results of the investigation are in, Lehner said.


Warren Ferster is the Editor-in-Chief of SpaceNews and is responsible for all the news and editorial coverage in the weekly newspaper, the spacenews.com Web site and variety of specialty publications such as show dailies. He manages a staff of seven reporters...