By Marina Malenic

A test of a defensive system designed to intercept long-range missiles failed this week, the Pentagon’s Missile Defense Agency said yesterday.

The test of the Ground-Based Midcourse Defense (GMD) system was a repeat of a Jan. 31 exercise that was also unsuccessful.

“The Missile Defense Agency was unable to achieve a planned intercept of a ballistic missile target during a test over the Pacific Ocean today,” the agency said in a Dec. 15 press statement.

No explanation for the failure was provided, but program officials “will conduct an extensive investigation to determine the cause of the failure to intercept the target.”

Prime contractor Boeing [BA] is also studying the test data.

“While yesterday’s result isn’t what we expected, we are analyzing the test data along side our customer to better understand the outcome,” a company spokeswoman said via e- mail. “As we continue to provide GMD with an unmatched level of availability and support, Boeing remains committed to the program’s success in understanding today’s events, and we look forward to demonstrating GMD’s capability in the future.”

Boeing’s main GMD subcontractors include Northrop Grumman [NOC], Raytheon [RTN] and Orbital Sciences Corp. [ORB].

GMD has succeeded in eight of 15 intercept attempts, according to MDA. Even proponents of the system said that record, combined with the latest test failure, is a setback for the program.

“This is a tremendous setback for the testing of this complicated system,” Riki Ellison, head of the Missile Defense Advocacy Alliance, said in a statement. “Much more troubling is the confidence in the…system that is currently deployed in Alaska and California.”

The 30 deployed interceptors have a similar configuration to the one used in the failed test, Ellison noted.

During this week’s test, an intermediate-range target missile flew from a test site on Kwajalein Atoll in the Marshall Islands. A long-range interceptor missile was launched from Vandenberg AFB, Calif., to intercept it, according to MDA.

Meanwhile, a sea-based X-Band radar and all sensors performed as planned, the agency said, and the interceptor missile successfully deployed a kill vehicle.

A date for “the next flight test will be determined after the failure’s cause is identified,” MDA’s statement says.

A Lockheed Martin [LMT]-led team that includes Raytheon [RTN] is competing against Boeing for a contract to continue development and sustainment of GMD. MDA is expected to announce the winner next year. Boeing is the 10-year incumbent on the project.