60 years of headlines from the Advanced Test Reactor

March 24, 2022, 3:01PMANS Nuclear Cafe
Cover of the April 1962 issue of Nuclear News (left), ATR core diagram appearing in October 1969 issue of Nuclear News (center), and cover of the October 1969 issue of Nuclear News (right).

The Department of Energy and Idaho National Laboratory announced this week that the sixth major core overhaul of the Advanced Test Reactor (ATR) is complete, after an 11-month outage that began in April 2021. The ATR was built as a key piece of mission support for U.S. Navy programs and first reached full power in 1969. Today it remains “the world’s largest, most powerful and flexible materials test reactor,” in the words of INL—quite a feat for a reactor that was planned over 60 years ago.

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