Report reveals serious flaws in U.S. missile defense system
WASHINGTON – Two serious technical flaws have been identified in the ground-launched anti-missile interceptors that the United States would rely on to defend against a nuclear attack by North Korea.
Pentagon officials were informed of the problems as recently as last summer but decided to postpone corrective action. They told federal auditors that acting immediately to fix the defects would interfere with the production of new interceptors and slow a planned expansion of the nation’s homeland missile defense system, according to a new report by the Government Accountability Office.
As a result, all 33 interceptors deployed at Vandenberg Air Force Base in Santa Barbara County, California, and Fort Greely, Alaska, have one of the defects. Ten of those interceptors – plus eight being prepared for delivery this year – have both.
Summing up the effect on missile-defense readiness, the GAO report said that “the fielded interceptors are susceptible to experiencing … failure modes,” resulting in “an interceptor fleet that may not work as intended.”
The flaws could disrupt sensitive on-board systems that are supposed to steer the interceptors into enemy missiles in space.
The GAO report, an annual assessment of missile defense programs prepared for congressional committees, describes the problems in terse, technical terms. Defense specialists interviewed by the Los Angeles Times and Tribune Washington Bureau provided more detail.
The interceptors form the heart of the Ground-based Midcourse Defense system, GMD for short. Four of the massive, three-stage rockets are stationed at Vandenberg and 29 at Fort Greely.
They would rise out of underground silos in response to an attack. Atop each interceptor is a 5-foot-long “kill vehicle,” designed to separate from its boost rocket in space, fly independently at a speed of 4 miles per second and crash into an enemy warhead – a feat that has been likened to hitting one bullet with another.
The GMD system was deployed in 2004 and has cost taxpayers more than $40 billion so far.
One of the newly disclosed shortcomings centers on wiring harnesses embedded within the kill vehicles’ dense labyrinth of electronics.
A supplier used an unsuitable soldering material to assemble harnesses in at least 10 interceptors deployed in 2009 and 2010 and still part of the fleet.
The same material was used in the eight interceptors that will be placed in silos this year, according to GAO analyst Cristina Chaplain, lead author of the report.
When Boeing Co., prime contractor for the GMD system, informed government officials of the problem last summer, they did not insist upon repair or replacement of the defective harnesses, according to the report.
The second newly disclosed defect involves a component called a divert thruster, a small motor intended to help maneuver the kill vehicles in flight. Each kill vehicle has four of them.
The GAO report refers to “performance issues” with the thrusters.
The GMD system is designed to repel a “limited” missile attack by a non-superpower adversary, such as North Korea. The nation’s defense against a massive nuclear assault by Russia or China still relies on “mutually assured destruction,” the Cold War notion that neither country would strike first for fear of a devastating counterattack.