Adolf Tolkachev

Adolf Georgievich Tolkachev (Russian: Адольф Георгиевич Толкачёв; 1927 in Aktyubinsk, Kazakhstan – September 24, 1986) was a Soviet Union electronics engineer who provided key documents to the United States Central Intelligence Agency (CIA) between 1979 and 1985. Working at the Soviet radar design house Phazotron as one of the chief designers, Tolkachev gave the CIA complete information about such projects as the R-23, R-24, R-33, R-27, and R-60, S-300; fighter-interceptor aircraft radars used on the MiG-29, MiG-31, and Su-27; and other avionics. Among the equipment compromised by Tolkachev was the passive phased array radar used by the MiG-31 Foxhound fighter, which the U.S. considered the most advanced airborne radar. He was executed as a spy in 1986.

Tolkachev claimed his distrust of the Soviet government arose from the persecution his wife's parents had suffered under Joseph Stalin. He told the CIA he was inspired by Aleksandr Solzhenitsyn and Andrei Sakharov.

From January 1977 to February 1978, Tolkachev attempted to approach cars with U.S. diplomatic license plates in Moscow five times, coincidentally approaching the CIA Moscow bureau chief Gardner Hathaway at a gas station, but the CIA was wary of counterintelligence operations by the KGB. On his fifth attempt the CIA assigned a Russian-speaking officer named John I. Guilsher to make contact with him. Eventually Tolkachev established his bona fides with intelligence data that proved to be of "incalculable" value to US experts. The U.S. Air Force completely reversed direction on a $70 million electronics package for the F-15 Eagle as a result of Tolkachev's intelligence, although historian Benjamin Fischer says that this was "the projected overall cost, not a cost savings".

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