Soviet space program omitted reports of failure or trouble". Out of fear of admitting any defeat, reports of cosmonauts' missions leaned towards an exaggerated positive spin rather than factual substance. "The USSR was famously described by Winston Churchill as 'a riddle, wrapped in a mystery, inside an enigma' and nothing signified this more than the search for the truth behind its space program during the Cold War. Although the Space Race was literally played out above our heads, it was often obscured by a figurative 'space curtain' that took much effort to see through" says Dominic Phelan in the book "Cold War Space
Cryptanalysis of the Enigma had brought the Poles a full set of Zygalski sheets that had been punched at Bletchley Park by John Jeffreys using Polish-supplied information, and on 17 January 1940, the Poles made the first break into wartime Enigma traffic—that from 28 October 1939. From that time, until the Fall of France in June 1940, 17 percent of the Enigma keys that were found by the allies, were solved at "PC Bruno". Just before opening their 10 May 1940 offensive against the Low Countries and France, the Germans made the feared change in the indicator procedure, discontinuing the duplication of the enciphered