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 secret was the plugboard permutation. On 15 December 1938, the German Army increased the complexity of Enigma enciphering by introducing two additional rotors (IV and V). This increased the number of possible "wheel orders" from 6 to 60. The Poles could then read only the small minority of messages that used neither of the two new rotors. They did not have the resources to commission 54 more bombs or produce 58 sets of Zygalski sheets. Other Enigma users received the two new rotors at the same time. However, until 1 July 1939 the "Sicherheitsdienst" (SD)—the intelligence agency of the SS