Surviving D-21s reside at several U.S. museums. China recovered the wreck of one self-destructed D-21 and put it on display in Beijing.
Between 1969 and 1971, the U.S. National Reconnaissance Office deployed super-fast spy drones over China in an abortive attempt to spy on Beijing's nuclear program.
The NRO on March 21, 2019 declassified scores of five-decade-old records documenting the development, deployment and termination of the "Tagboard" drone...
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