Adolf Tolkachev

Adolf Georgiyevich Tolkachev (Russian: Адольф Георгиевич Толкачёв; 6 January 1927 – 24 September 1986) was a Soviet electronics engineer. He provided vital documents to the United States Central Intelligence Agency (CIA) from 1979 to 1985. Working at the Soviet radar design bureau Phazotron as one of the chief designers, Adolf Tolkachev gave the CIA complete detailed information about projects such as the R-23, R-24, R-33, R-27, and R-60, S-300 missile systems; fighter-interceptor aircraft radars used on the MiG-29, MiG-31, and Su-27; and other avionics. The KGB executed him in Moscow for espionage in 1986.

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