"...As of April 2018, the Pentagon deploys 44 ground-based interceptors (GBIs)–40 at Fort Greely, Alaska, and four at Vandenberg Air Force Base, California. ...As of April 2018, the Pentagon deploys 44 ground-based interceptors (GBIs)–40 at Fort Greely, Alaska, and four at Vandenberg Air Force Base, California. Twenty of the 40 interceptors deployed in Alaska are armed with an older CE-1 kill vehicle that has not had a successful flight intercept test since 2008. In 2017, the Trump administration announced its plan to deploy twenty more GBIs to be installed in a fourth missile field in Ft. Greely beginning in the FY 2021 timeframe. According to the Missile Defense Review, all 64 interceptors would be ready by 2023. These interceptors will be armed with the new, under-development Redesigned Kill Vehicle (RKV), which is intended to enhance the performance of the current EKV. But the RKV has been plagued by reliability and design problems, which led to the Pentagon stopping work on the program in May 2019 and, after a short review, terminating the program in August. The new timeline for expanding the GMD system to 64 interceptors is uncertain."
Reference: www.armscontrol.org
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