Zond 5 Reaches Moon

On 3 August 1964 Command number 655-268 issued by Central Committee of Communist Party for the first time set the objective for the Soviet Union to put one man on the moon and return him safely to earth - ahead of the Americans (who had begun over three years earlier, in April 1961). The spacecraft designed for this purpose were called the L3 complex. The L3 would be launched into low earth orbit by a single launch of the N1 launch vehicle, then already in development. The combined launch vehicle/spacecraft was termed the N1-L3.

The L3 would utilise the same lunar orbit rendezvous method to achieve moon landing that was selected for the Apollo program. It would consist of a fourth stage (Block G) to take the L3 from low earth orbit to trans-lunar trajectory; a lunar orbiter with a Soyuz re-entry capsule for return to earth (LOK); a lunar lander (LK) for the landing of a single cosmonaut on the surface of the moon; and a deceleration stage (Block D) which would brake the L3 complex into low earth orbit and then take the LK lander to near zero velocity above the surface of the moon.

The work for the project was split as follows:

• OKB-1 (Korolev): General management, design of Blocks G and D, design of the engines for Block D, L, and LOK.

• OKB-276 (N. D. Kuznetsov) - engines for Block G

• OKB-586 (Yangel) - the LK lunar lander and the engines for the lander Block E rocket stage

• OKB-2 (Isayev) - the complete propulsion system (tanks, controls, engines) for the LOK lunar orbiter Block I stage.

• NII-94 (V. I. Kuznetsov) - guidance systems for the L3 (LOK/LK/Block D) lunar complex

• NII-AP (Pilyugin) - guidance systems for the LOK

• NII-885 (Ryazanskiy) - radio telemetry systems

• GSKB Spetsmash (Barmin) - N1 launch complex and N1/L3 ground systems

• Saturn Factory (Lyulka OKB) - 40 tonne thrust engines for the Blocks G and V. They would also work with OKB-1 in design of the 8.5 tonne thrust Block D engine, derived from the third stage engine developed for Korolev's GR-1/8K713 FOBS missile.

The plan was for the first launch of the N1 to be in the first quarter of 1966, with the first lunar landings in 1967 to 1968, ahead of the American goal of 1969.

The LK as designed had a mass of 5,560 kg, with the Block E stage weighing 2,950 kg. Takeoff mass of the LK was 3,800 kg.

The lunar flight plan was as follows:

• The L3 complex is injected into low earth orbit. Up to one day could be spent in earth orbit before trans-lunar injection.

• The Block G stage burns to propellant depletion, putting the complex into translunar trajectory. The Block G then separates.

• The Block D stage performs up to two mid-course corrections and puts the LOK/LK/Block D stack into elliptical lunar orbit. The Block D can be restarted after up to 3.5 days of translunar coast and 4 days in lunar orbit.

• The LK pilot-cosmonaut spacewalks from the LOK to the LK and checks out the lander and Block D systems.

• The LK/Block D separate from the LOK. The Block D brakes the LK to near zero velocity above the lunar surface, then is separated and crashes on the moon.

• The LK ignites its engines and hovers to a piloted soft landing on the surface.

• The LK cosmonaut exits the LK to the lunar surface. From six to 24 hours is spent on the lunar surface.

• The LK Block E launches itself from the LK landing gear into lunar orbit. It rendezvous with the LOK. The LK cosmonaut spacewalks from the LK back to the LOK with the lunar samples.

• After up to one day in lunar orbit, the LOK's Block I engine puts the LOK into trans-earth trajectory. 3.5 days is spent on the coast back to earth.

• Before re-entry, the descent module separates from the LOK with the two cosmonauts aboard, It re-enters the earth's atmosphere at 11 km/sec and lands on the territory of the USSR.

In December 1964 Keldysh and the State Commission from the Soviet Academy of Sciences reviewed the final design for the L3. It was approved by the government on 10 February 1965. This resulted in a design freeze of all elements by the end of that month. The plan at that point was for fabrication drawing release in April to June 1965; mock-up inspection in second quarter of 1966; first flight in fourth quarter of 1966; ground complex completion second quarter 1966; first flight by end of 1966.

The industrial teams went ahead with these plans. Because of concerns about crew safety and the inability to obtain a successful launch of the N1 (see the N1 Story) at various times from 1965 to 1974 alternative scenarios were proposed. These included:

• Dual launches of N1's to provide backup spacecraft
• Lunar surface rendezvous of two LK's to provide backup return spacecraft
• Launch of the crew in an earth-orbital version of the Soyuz spacecraft separately from the N1. The Soyuz would dock with the N1-L3 complex, the crew would spacewalk to the N1-L3 before casting off the Soyuz and continuing on to the moon. This alternative was considered in the event the N1 could not be man-rated
• Scouting of landing sites by unmanned Lavochkin landers which would provide radio beacons to guide the LK to a safe precision landing.

Soon after the beginning of the L3 project studies work also began on a lunar base to follow the initial single cosmonaut lunar landing. These studies were undertaken by Korolev's OKB-1 with Chief Designer Vladimir Pavlovich Barmin's GSKB SpetsMash (State Union Design Bureau of Special Machine-Building) as principal subcontractor. The project was known to SpetsMash as the 'Long-term Lunar Base' (DLB) and to OKB-1 as 'Zvezda'. Consideration was given to using the same elements in expeditions to other planets. Under the DLB studies SpetsMash defined purposes of the base, the principles of its construction, phases of its deployment and composition of its scientific and support equipment.

Zvezda would have utilised unmanned spacecraft designed by the Lavochkin OKB to conduct initial reconnaissance of the prospective moon base site. These would use lunar soil core drills to obtain samples of the soil and return them to earth for analysis, and Lunokhod rovers to survey the site. If the site was found to be satisfactory, these craft had radio beacons which would guide follow-on elements of the base to precision landings.

The manned elements apparently used the improved L3 complex (designed for the follow-on two man lunar landings) to ferry manned crews from earth orbit to lunar orbit and then from lunar orbit to the surface and back. The Block Sr LOX/LH2 stage would be used to insert the components of Zvezda into low lunar orbit. Ambitious articulated mobile nuclear-powered Lunokhod laboratories would take the cosmonauts from the landing sites on long-duration traverses of the lunar surface. The Lunokhods were equipped with core samplers and manipulators so that the crew could conduct collection of surface samples from within the pressurised cab without the need to always exit the ship and conduct surface operations in space suits.

These initial studies came to an end in May 1974 with the cancellation of the N1 launch vehicle upon which they relied. Unmanned elements of Zvezda designed by the Lavochkin and using lunar core sampling drills designed by Barmin flew in 1969-1976 under the 'Luna' program. Although these flights were conducted in direct reconnaissance support of a manned lunar landing and lunar base, at the time it was declared that no Soviet manned lunar landing program existed, and that these unmanned flights represented a way to achieve the results of the American Apollo program without such expense and risk to life. After a number of launch vehicle failures this series of probes had some success. Luna 15 crashed while attempting to land on the moon while the Apollo 11 astronauts were actually on the surface. But then on September 20, 1970 Luna 16 safely soft landed on the moon and then returned lunar soil to Soviet territory. Lunokhod 1 travelled about a small portion of the Sea of Rains and returned photographs. Luna 19 mapped the gravity field of the moon in preparation of later manned flights. Luna 20 returned to earth more lunar soil, and Lunokhod 2 roved around an area representing the transition zone between the lunar maria and the highlands.

Although the Zvezda project was cancelled, the new head of NPO Energia, Glushko, still considered the establishment of a moon base to be a primary goal for his country. While the Americans had achieved the first moon landing, it was known that all moon flights after Apollo 17 had been cancelled. There existed an opportunity, through establishment of a permanent moon base, to steal the lead in the space race once again. Furthermore, analysis of the results of the previous unmanned and manned indicated that the moon was suited for a variety of 'special investigations', and that a permanent lunar expeditionary complex (LEK) would be required to accomplish this.

To launch the elements of the LEK, Glushko designed a new launch vehicle, the Vulkan. The Vulkan would use the LOX/LH2 engine technology developed for the US Space Shuttle in the core stage. This would be surrounded by six strap-on boosters, using LOX/Kerosene engines, to be developed by NPO Yuzhnoye in the Ukraine. This use of cryogenic propellants represented a complete turnaround for Glushko, who had advocated use of storable but toxic rocket propellants in a bitter fight with Korolev and Mishin for fifteen years.

The Vulkan was designed to deliver 230 tonnes into a 200 km low earth orbit; 60 tonnes to lunar orbit; and 22 tonnes to the lunar surface.

The LEK consisted of expeditionary and transport lunar spacecraft (Chief Designer K D Bushchev) and equipment for the permanent base station (Chief Designer I S Prudnikov).

The expeditionary and transport craft consisted of:

• LEK (Lunar Expeditionary Spacecraft). As in the original LK lunar lander, this would be taken to near zero velocity near the lunar surface by the Vulkan Block V 'lunar crasher' rocket stage. It would then descend to the lunar surface using a landing stage nearly identical to the American lunar module descent stage. This landing stage however would primarily provide propulsion of the upper Ascent/earth recovery stage to a trans-earth trajectory. The Ascent/earth recovery stage consisted of a re-entry capsule in the shape of but larger than the Soyuz descent module, encapsulated in a larger pressurised volume providing crew quarters and equipment storage.

• LZhM (Laboratory-Residence Module) for three men as the home base for living and working during the expedition. This used a simpler descent stage with minimal propellant for the soft landing on the moon following separation from its Block V lunar crasher stage.

The equipment of the permanent base station consisted of:

• Lunokhod - a large manned wheeled mobile pressurised laboratory with a working radius of up to 200 km from the base. The Lunokhod would also be used for loading and unloading operations, and had a grader for burying the nuclear reactors which would power the complex and the laying out of 'streets' and protective berms for the base itself.

• LZM (Laboratory-Factory Module) provided biological and physics laboratories in two lobes. In the other was a factory for production of oxygen from the lunar soil. This used the same simple descent module as the LZhM.

• Nuclear power stations to power all of the modules of the lunar base. Each module of the complex was outfitted with its own autonomous power station. After landing, this would be removed from the landing stages and buried a distance away from the module before being put into operation.

• Transport spacecraft for delivery of expendable and consumable equipment and supplies to the surface. These would use the simple descent module.

• Study of other planets, astrophysics, and astronomy using telescopes covering the entire electromagnetic spectrum from the stable platform of the lunar surface

• Medical and biological studies, including perhaps the production of new bacteriological warfare agents

• Production of new materials and gases from the lunar soil (including oxygen for human activities and eventually as rocket oxidiser) and the collection of helium isotopes from solar wind for nuclear fusion reactors on earth

Delivery of the components of the LEK would be in three stages:

• Stage 1 - Three Vulkan launches would deliver the LZhM, Lunokhod (with scientific apparatus and consumable for 1.5 years), and an LEK with a crew of three.

• Stage 2 - Two Vulkan launches to land another LZhM, an open-cabin Lunokhod, and an LEK with a crew of three men for an occupation of six months.

• Stage 3 - One Vulkan launch of the LZM and further scientific apparatus (three months after the start of stage 2). This would give the base the capability to produce its own oxygen.

The LEK study and initial Vulkan design were completed by the end of 1975. However the Academy of Sciences Expert Commission decided that the LEK Project should be deferred into the next century. Soon thereafter all of NPO Energia's efforts were directed to support development of the reusable launch vehicle Energia/Buran.

A modified version of the LEK was proposed in the 1980's using the Energia launch vehicle. Because of the much lower payload capability of the Energia (88 tonnes to low earth orbit versus the 230 tonnes of the Vulkan) this would use a new LOK lunar orbital spacecraft (unrelated to the earlier Soyuz-based LOK) and an LK lander based on the Vulkan LEK lander. The LOK and LK lander would be inserted into lunar orbit by separate Energia launches. As in the earlier projects, prior to the Energia launches an unmanned Lunokhod would scout the region, allowing selection of a suitable landing site, and serve as a landing beacon for the precision LK landing. After rendezvous and docking in lunar orbit, three of the five crew aboard the LOK would transfer to the LK and descend to the lunar surface. After 5 to 10 days on the surface, the ascent stage of the LK would return to lunar orbit, and the crew would transfer back to the LOK. The LOK would remain in lunar orbit for a full lunar day (29 days) until returning to earth. This proposal did not attract support and further development of the concept was not continued. Thus ended lunar base studies in Russia.