WASHINGTON Jan 28 (Reuters) - The U.S. Missile Defense Agency should consider redesigning a key part of its ground-based missile defense system after a series of test failures in recent years, the Pentagon's chief arms tester said in a new report due to be released Wednesday.
"The flight test failures that have occurred during the past three years raise questions regarding the robustness of the Exoatmospheric Kill Vehicle (EKV)," said the report, referring to the Raytheon Co-built part of the rocket used to hit enemy missiles and destroy them on impact.
Michael Gilmore, the Pentagon's director of operational test and evaluation (DOT&E), said the agency should redo the intercept test that failed last July and consider whether to redesign the "kill vehicle" and shore it up against failure.
Boeing Co manages the Pentagon's program to deal with long-range missile threats, while Raytheon and Orbital Sciences Corp build the interceptors and rockets used by the system.
Gilmore's report, which circulated in Washington on Tuesday ahead of Wednesday's release, drew praise from two groups that closely track developments on the Ground-based Midcourse Defense (GMD) system designed by Boeing Co.
"It appears that DOT&E has finally come to the conclusion that the GMD interceptors ... may be so flawed that a complete redesign is required," said Kingston Reif, with the nonprofit Center for Arms Control and Non-Proliferation.
He said neither of the two current versions of the so-called "kill vehicle" designed by Raytheon, had seen a successful flight intercept test since 2008.
Reif said Gilmore's latest report raised questions about the Boeing-run missile defense system, and Defense Secretary Chuck Hagel's plan to build and deploy 14 more existing ground based interceptors, which have the older "kill vehicles," in Alaska at a cost of $1 billion.
Riki Ellison, founder of the Missile Defense Advocacy Alliance, said redesigning the "kill vehicle" was "worth the time and investment it will take to create it, develop it and test it," given America's need to defend against possible enemy missile attacks.
He said he expects the Pentagon's fiscal 2015 budget plan to ask for $560 million in funding over the next five years to develop a new kill vehicle, with an eye to starting their use in 2019. Additional funding would be needed to upgrade and fix the existing interceptors in the meantime, he added.
"It is the right thing to do the due diligence, effort and engineering to make this missile as good as our nation can with today's technologies and research," Ellison said.
Nuclear-armed Russia says it fears a Western anti-missile shield in Europe is meant to undermine its security, upsetting the post-Cold War strategic balance. Efforts to turn years of confrontation over the issue into cooperation have failed.