By Andrea Shalal
WASHINGTON (Reuters) - The U.S. Missile Defense Agency on Thursday said it conducted a successful test of the ground-based U.S. missile defense system managed by Boeing Co aimed at demonstrating the effectiveness of a redesigned "kill vehicle" or warhead built by Raytheon Co.
The test purposely did not include an intercept by a ground-based interceptor launched from Vandenberg Air Force Base in California, but was designed to observe the in-flight performance of the redesigned components and collect data on countermeasures carried by the target, according to statements by the agency and the companies involved.
Raytheon's exoatmospheric kill vehicle, or EKV, is built to destroy incoming ballistic missiles by colliding them while they are still in space, a concept called "hit to kill."
Thursday's test was designed to demonstrate the ability of new "divert thrusters" that were developed by Raytheon to maneuver the warhead after a test failure several years ago.
The test, which involved various elements of the U.S. ballistic missile defense system, took place as U.S. officials said North Korea appeared to be preparing for a possible space launch that could advance its development of intercontinental ballistic missiles.
News of the possible North Korean space launch comes weeks after a fourth nuclear test conducted by Pyongyang on Jan. 6 that has raised concerns worldwide.
MDA said program officials would evaluate the performance of the U.S. missile defense system during Thursday's test using telemetry and other data gathered during the test.
Raytheon's EKV has an advanced, multi-color sensor used to detect and discriminate incoming warheads from other objects in space. It has its own propulsion, communications link, discrimination algorithms, guidance and control system and computers to support target selection and intercept.
Riki Ellison, founder of the nonprofit Missile Defense Advocacy Alliance, said the test demonstrated new technology developed to make the EKV more reliable, which in turn would allow the U.S. military to shoot fewer interceptors at each incoming missile threat.
He said the successful test would "provide confidence to our public, reliability to the NORTHCOM (U.S. Northern Command) commander and deterrence against North Korea," he said.
Ellison urged U.S. officials to add 10 more ground-based interceptors to the California site to provide an additional layer of defense for Hawaii and the western United States.
The U.S. military is already adding 14 interceptors to the 30 already in place, but those missiles will go to the other interceptor site in Alaska.
(Editing by Nick Macfie)