Soviet crewed lunar programs
The Soviet government publicly denied participating in such a competition, but secretly pursued two programs in the 1960s: crewed lunar flyby missions using Soyuz 7K-L1 (Zond) spacecraft launched with the Proton-K rocket, and a crewed lunar landing using Soyuz 7K-LOK and LK spacecraft launched with the N1 rocket.
Sergei Korolev, the senior Soviet rocket engineer, was more interested in launching a heavy orbital station and in crewed flights to Mars and Venus.
In its preliminary Moon plans, Korolev's design bureau initially promoted the Soyuz A-B-C circumlunar complex (A-B-V in Russian) concept under which a two-crew spacecraft would rendezvous with other components in Earth orbit to assemble a lunar flyby excursion vehicle.
The proposal disappeared though with Kennedy's assassination two months later,[6] but nevertheless foreshadowed the Apollo-Soyuz mission, which enabled subsequently the Shuttle-Mir program and the ISS.
In September 1968 Zond 5 carried the first Earth lifeforms, including two tortoises, to travel around the Moon and return safely.
Planned for 8 December 1968 for priority over the US, a first crewed mission of the L1 (Zond) was canceled due to the insufficient readiness of the capsule and rocket.
After Apollo 8 won the first (lunar orbit) phase of the Moon Race at the end of 1968, the Soviet leadership lost political interest in the L1 (Zond) program.
The crewed landing plan adopted a similar method to the single launch and lunar orbit rendezvous of the Apollo project.
After a few hours on the lunar surface, the LK's engine would fire again using its landing structure as a launch pad, as with Apollo.
To save weight, the engine used for landing would blast the LK back to lunar orbit for an automated docking with the LOK.
One group was commanded by Vladimir Komarov and included Yuri Gagarin, and was to prepare for qualification flights of the Soyuz in Earth orbit and a Proton-launched cis-lunar mission (Gagarin, Nikolayev, Komarov, Bykovsky, Khrunov; Engineer-Cosmonauts: Gorbatko, Grechko, Sevastyanov, Kubasov, Volkov).
Komarov later died in the Soyuz 1 spaceflight when his parachute malfunctioned causing his capsule to smash into the earth at high speed.
The complete L3 lunar expedition complex with the 7K-LOK and LK for the Moon flyby and landing was prepared for a fifth launch, using a modified N1 rocket in August 1974.
To gain technical and scientific interest in the program, the modified multi-launched N1F-L3M missions were planned to have significantly more time on the Moon's surface than Apollo.
[10] A Moon base, Zvezda, that was proposed later, developed mockups of expedition vehicles[11] and surface modules,[12] and "Vulkan-LEK" project were not adopted for economic reasons.
