Soviet space program
Notable setbacks included the deaths of Korolev , Vladimir Komarov ( in the Soyuz 1 crash ) , and the Soyuz 11 crew between 1966 and 1971 , and development failure of the N-1 rocket ( 1968–1974 ) intended to power a crewed lunar landing , which exploded shortly after lift-off on four uncrewed tests . 
<triplet> Vladimir Komarov <subj> Soyuz 1 <obj> astronaut mission <triplet> Soyuz 1 <subj> Vladimir Komarov <obj> crew member