March 28, 2012
Ground-Based Midcourse (GMD) Interceptors and Silos
The GMD’s 30 deployed Ground-Based Interceptors (GBIs) are emplaced in three silo fields at Fort Greely in central Alaska and four silos at Vandenberg Air Force Base in California. There is also at least one silo reserved for testing at Vandenberg. Currently, 26 interceptors are deployed at Fort Greely and 4 at Vandenberg. However, no more than 20 of these are apparently currently considered to be operational.
The first six GBIs deployed were placed in the six-silo Missile Field 1 at Fort Greely. The first operational GBI interceptor was emplaced at Fort Greely on July 22, 2004 and all six silos were filled by the end of November, 2004. By the end of the year, two additional GBIs had been deployed in silos at Vandenberg, bring the total deployment to eight.
The ninth GBI was emplaced on September 18, 2005 at Fort Greely. This was the first interceptor deployed in the 20-silo Missile Field #3.
The 24th GBI was deployed in September 2007. This deployment was significant because it marked the end of deployment of GBIs equipped with the original Capability Enhancement One (CE-I) Exo-atmospheric Kill Vehicle (EKV), and was followed by a gap of more than a year before the next GBI deployment.
The first two GBIs equipped with the new CE-II kill vehicle were deployed in late 2008, and all subsequent new production GBIs used this version of the kill vehicle.
In its April 2009 budget announcement for FY2010, the MDA announced that it would decrease the planned numbers of both deployed GBIs and operational launch silos from 44 to 30. Under this plan the 14 silos of the planned missile field #2 at Fort Greely would not be built, and 14 non-deployed GBIs would be used for testing and as operational spares.
According to a May 2010 DoD report, “This reduction in silos still provides the United States with a substantial inventory of operational GBIs considering the very limited number of [intercontinental ballistic missile] launch complexes in North Korea and Iran.” In 2009, Joint Chiefs of Staff Vice-Chairman General James Cartwright had stated that 30 operational silos were “a heck of a lot more [than needed] for a rogue.”
Under political pressure, however, the MDA subsequently decided to finish Missile Field #2 and its construction had been completed by early 2012, although as of early March it had apparently not yet been declared operational. The six-silo Missile Field #1 will be placed in a storage mode, from which it could be reactivated in two years. Missile Field 1 has been reported to have significant environmental problems including mold contamination and leaking anti-freeze.
The 30th GBI was deployed in September 2010. As additional GBIs were produced beyond the first 30 deployed, they were deployed in place of older GBIs. According to the GAO, ten of the thirty deployed GBIs have the new CE-II EKV. However, deployment of additional new EKVs has been temporarily suspended due to problems with the CE-II revealed during testing. In addition, MDA has stated that the GBIs equipped with the CE-II EKV will not be considered operational until a flight test with one is successfully completed (the next opportunity is CVT-01, a non-intercept test currently scheduled for July 2012).
In February 2012, the MDA stated that, if necessary, up to eight additional GBIs could be deployed by 2015 into otherwise empty silos at Fort Greely, bring the total number of deployed interceptors to 38. This figure does not include using the six silos in the deactivated Missile Field 1.
Current procurement plans call for total of 57 GBIs to be produced (some of these have already been expended in tests).
 Missile Defense Agency, Fiscal Year (FY) 1010 Budget Estimates, Overview, April 27, 2009. Available at: http://www.mda.mil/global/documents/pdf/budgetfy11.pdf.
 John Liang, “DoD Report: Only 30 Operational GBIs Needed to Defend U.S. Homeland,” Inside Missile Defense, October 6, 2010.
 Amy Butler, “Midcourse Correction,” Aviation Week and Space Technology, August 24, 2009, p. 24.
 When the decision to cancel missile field #2 was reversed, it was originally announced that field #1 would be decommissioned, which would largely return the site to its condition before the building of silos. However, it was subsequently decide to place the field #1 in storage. This costs about $4 million plus $500,000 a year for maintenance. Testimony of Lieutenant General Patrick O’Reilly, Defense Subcommittee of the Senate Appropriations Committee, May 25, 2011. Missile Field 1 lacks backup power and other features desired in operational silos, and also has environmental problems, such as mold contamination.
 FY2011 budget summary.
 “MDA: Eight More Alaska-Based Interceptors Could Be Field by 2015,” InsideDefense.com, February 29, 2012.