by firing the engine on the service module to slow the complex and enter lunar orbit since the Apollo complex traveled with the Command Module and Lunar Excursion Module (LEM) facing back towards the Earth. Once in orbit, the LK with Block D would separate from the LOK and descend toward the surface of the Moon using the Block D engine. After Block D exhausted its fuel, the LK was to separate and complete landing using its own Blok E engine. On the Moon, the cosmonaut would take Moon walks, use Lunokhods, collect rocks, and plant the Soviet flag. 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. The cosmonaut then would spacewalk back to the LOK carrying rock samples. The LK would then be cast off, after which the LOK would fire its rocket for the return to Earth. Launch schedules As of 1967, the L1/L3 launch schedules were: UR-500K(Proton)/L1(Zond) program 2P: Develop Block D stage (February or March 1967) 3P: Develop Block D stage (March 1967) 4L: Uncrewed lunar flyby (May 1967) 5L: Uncrewed lunar flyby (June 1967) 6L: Crewed lunar flyby (June or July 1967) 7L: Crewed lunar flybys (August 1967) 8L: Crewed lunar flybys (August 1967) 9L: Crewed lunar flybys (September 1967) 10L: Crewed lunar flybys (September 1967) 11L: Crewed lunar flybys (October 1967) 12L: Crewed lunar flybys (October 1967) 13L: Reserve spacecraft N1/L3 program 3L: Develop LV & Blocks G&D (September 1967) 4L: Reserve 5L: LOK/LK uncrewed (December 1967) 6L: LOK/LK uncrewed (February 1968) 7L: Crewed LOK/uncrewed LK (April 1968) 8L: Crewed LOK/uncrewed LK (June 1968) 9L: Crewed LOK/uncrewed LK with LK lunar landing (August 1968) 10L: First crewed lunar landing (September 1968) 11L: Reserve 12L: Reserve Korolev's death in 1966, along with various technical and administrative reasons, as well as a lack of financial support, resulted in both programs being delayed. Cosmonauts In 1966, two cosmonaut training groups were formed. 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