By Andrea Shalal-Esa
WASHINGTON (Reuters) - A failed U.S. missile defense test last week may be linked to a faulty battery that prevented an interceptor from separating from the rest of the rocket, an industry source said, citing initial findings in an investigation.
"The initial look at the data indicates the problem was in the power suite, with the battery," said the source, who was not authorized to speak on the record. If that theory is proven, it would point to a component-manufacturing issue or quality control problem, the source said.
A test of the only U.S. defense against long-range ballistic missiles failed last Friday, the third consecutive failure involving the interceptor system managed by Boeing Co, the Defense Department said.
Neither of the previous failures involved battery problems, investigations showed.
Pentagon officials have launched a detailed and extensive review of the failed test, but that could take months to complete, said one defense official. Officials have been tight-lipped about any initial findings.
Boeing said it would continue to analyze test data along with military officials to better understand the outcome of the test. A company spokeswoman declined comment on whether the inceptor's battery was the suspected cause of the test failure, and had no immediate comment on the manufacturer of the battery.
The booster was built by Orbital Sciences Corp, while the actual interceptor, or "kill vehicle," is built by Raytheon Co. It is designed to hit and destroy the target warhead outside the Earth's atmosphere.
Northrop Grumman Corp builds communication systems and fire-control equipment for the system.
Raytheon and other subcontractors on the program declined comment, referring all questions to the Missile Defense Agency, which says only that the investigation is ongoing.
The failed test is deepening long-standing political divisions over U.S. missile defense, prompting Republicans to call for increased funding on missile defense programs because of escalating threats from North Korea and Iran.
At the same time, many Democrats say the test failure should prompt a review of plans by Defense Secretary Chuck Hagel to buy 14 more interceptors at a cost of $1 billion, to add to the 30 it already has in California and Alaska.
Four U.S. Republican lawmakers on Friday urged Hagel to conduct another test of the missile defense system this year and to make development of a next-generation interceptor a top priority.
The lawmakers said the cause of the failed July 5 missile defense test was not yet clear, but they argued that President Barack Obama's cuts in spending on missile defense had reduced funding for needed tests and maintenance of the system.
Riki Ellison, chairman and founder of the Missile Defense Advocacy Alliance, said preliminary findings into the missed intercept pointed to a failure of the final stage of the ground-based interceptor to separate, rather than a failure of the interceptor to detect, track or hit the target.
Ellison agreed that the interceptor needed to be retested as soon as possible, and that once it was clear what caused the problem, all the existing missiles in California and Alaska would have to be checked for similar problems.
Until other tests validated the ability of the system to actually hit a target, U.S. military officials would also likely have to adjust their response and fire off additional interceptors in the event of any threat, he said.
The Pentagon has said the test will not affect its decision to add 14 new interceptors. The United States currently has 26 interceptors deployed at Fort Greely in Alaska and four at Vandenberg Air Force Base in California. The interceptor used in last week's test came from the California base.
(Editing by Philip Barbara)