Soyuz Lunar Spacecraft versions, flown and planned

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The Soyuz 7K-L1 Zond (see also unmanned lunar programs: Luna and Zond) spacecraft was supposed to launch men to circle the Moon, not going to the lunar orbit, but circle it as a lunar flyby. That was part of the Space Race (see article The Space Race). Design of Soyuz 7K-L1 was based on the Soyuz 7K-OK (see article Soyuz spacecraft first generation). 

The biggest difference was replaced orbital module by the support cone and parabolic antenna and reserve parachute. It was supposed to carry 2 cosmonauts. However, there were serious problems with the Proton rocket.  
Zond: artist picture

 Zond 5 was an unmanned spaceflight launched in September 1968. It was the second craft to circle the Moon and the first one which returned safely to Earth and which had onboard two tortoises, mealworms, wine flies, plants and other lifeforms. It was launched by Proton-K with Block D upper stage to perform scientific goals during the lunar flyby.

N1/L3 project was approved in February 1967. First test would use Soyuz 7K/L1P prototype. It was not able to reentry. Cosmos 146 was the first test flight and was launched on March 10, 1967. It put the spacecraft into the elliptical Earth's orbit. The Block D worked correctly in that first test. The next Cosmos 154 launched on April 8 reached the Earth's orbit but the Block D failed. All the attempts has shown that they wouldn't be ready to launch safely cosmonauts to the Moon and get them safely back before the Apollo. 

 The N1 rocket had about 105 m together with L3 stage. N1/L3 was composed of 5 stages, the first 3 stages N1 for reaching the lower Earth's orbit, and another 2 stages L3 for the lunar trip and lunar orbit. 

U.S. Saturn V vs. Soviet N1/L3

Soyuz 7K-L3 or LOK was a Soviet manned spacecraft which was supposed to launch man to the Moon. LOK consisted from the main ship and the lander, bringing one cosmonaut on the lunar surface. 

 The LOK consisted of docking mechanism, orbital engine system providing the orientation on the way, living space, descent module, transition depressurized part, equipment pressurized part, engine part, engine assembly.

 Three unmanned Soyuz-LOK flight were flown. The first flight was modification of Soyuz 7K/L1. It was launched into orbit on a Proton rocket on December 2, 1970. Another two flights were launched on June 26, 1971 and November 23, 1972, both failed boosters. 7K-LOK and LK for the unmanned lunar flyby and landing was prepared, however the N1/L3 program was cancelled in May 1974. 

 Lunar craft LK was lander developed in 1960s as a part of the Soviet Lunar program. It acted the same way as Apollo Lunar Module. Several lunar craft were flown in orbit, never reaching the lunar orbit or surface. LK had pressurized part for the cosmonaut and life-support system, 4 landing legs with attached batteries, drilling arm and 2 antennas. 

 LK was tested unmanned in the Earth's orbit 4 times as Kosmos 379, 382, 398, and 434. It was launched by Soyuz-L rocket. All flights went well, so the LK was considered ready for manned flights. 
Some basic facts to compare LK vs. Apollo LM:
  • LK was lighter than LM
  • First LK carried only one cosmonaut compared to 2 astronauts in LM
  • LK didn't have docking tunnel as LM had
  • It had different landing profile
  • They both used landing legs as launch pad as well
  • LK had primary and reserve engines to ensure the ascent, LM had only single engine, and no back ups. 
Soyuz LK vs. Apollo LM drawing in scale to each other


LK - lunar craft - lunar lander test unit


In the end, do not forget on successful lunar projects such as lunar rovers Lunar vehicles. American rover helping astronauts to transport on lunar surface, or Soviet robotic vehicle Lunokhod, fully controlled from the ground. 

American human rover vs. Soviet robotic rover

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