After a series of fiascos, the US missile defence system has performed a successful intercept test on Sunday, destroying a dummy enemy missile.
During the test, a ground-based interceptor was launched from Vandenberg Air Force Base in California to hit a Lockheed Martin-built target launched from the US Army's Reagan Test Site on Kwajalein Atoll in the Republic of the Marshall Islands.
Unlike in five previous cases, the US Department of Defence said, all components of the system performed as designed, hitting the 14-metre target configured to closely resemble the capabilities of ground-launched missiles with a 3,000 to 5,000km range.
"This is a very important step in our continuing efforts to improve and increase the reliability of our homeland ballistic missile defence system," said Missile Defense Agency (MDA) Director Vice Admiral James Syring.
Program officials will spend the next several months assessing the performance of the system using telemetry and other data obtained during the test.
The test marked the first successful intercept by Raytheon's Exoatmospheric Kill Vehicle Capability Enhancement II, or EKV CE-II, which failed in both previous tests conducted in 2010.
The intercept will help validate the troubled Boeing-run Ground-based Midcourse Defense (GMD) system which provides the sole US defence against long-range ballistic missiles, and the Raytheon kill vehicle that separates from the rocket and hits an incoming warhead.
Reuters reported on Friday that the Pentagon is restructuring its $3.48bn contract with Boeing for management of the missile defence system to put more emphasis on maintenance and reliability.
Earlier this month, Syring said that another test failure would have forced the Pentagon to reassess its plans to add 14 more interceptors to the 30 already in silos in the ground in Alaska and California.
Jim Chilton, vice president of Boeing Strategic Missile & Defense Systems, said the system demonstrated performance under "an expanded set of conditions that reflect real-world operational requirements." Boeing said the operational complexity of the GMD system was "a major engineering challenge."
Raytheon underscored the importance of testing and said Sunday's successful intercept kept the United States on target to increase its interceptor inventory to 44 from 30 by 2017.
Northrop Grumman integrated data from US missile warning satellites and sea-based radars to help identify, track and destroy the target.
Ten of the interceptors now in place carry the kill vehicle used in Sunday's test. The other 20 carry an earlier kill vehicle that failed in a July 2013 test. Syring has said a fix will be implemented for that issue by year's end.