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Kosmos-2 launch vehicle


Soon after launch of the first Soviet "Sputniks," both military and scientific organizations in the USSR expressed interest in sending small semi-experimental payloads into space using somewhat smaller rockets than R-7. Yangel's R-12 seemed to be the best candidate for transformation into such launcher. According to the official history of the Yuzhnoe design bureau, as early as in 1956, Dimitry Ustinov requested OKB-586 to study a possibility of launching small satellites onboard the R-12 missile. (98)

OKB 586 started work on the project encoded 63S1 as early as April 1960. On August 8, 1960 Central Committee of the CPSU and the Council of Ministers of the USSR signed a resolution approving R-12-based launch-vehicle as well as development of ten compatible satellites for scientific research.

While R-12 itself needed minimal modifications to be used as the first stage of launch-vehicle, the upper stage for orbital injection had to be developed from scratch. Further, it had to compensate for a major flaw of the first stage - low specific impulse - about 20 percent lower than that of the first stage engine on Korolev's R-7.

Glushko's OKB-456 worked on the engine for the second stage. Known as RD-119, it had a single small-size combustion chamber with a disproportionately large nozzle allowing up to a 1,350 times expansion of the exhaust gases at the nozzle exit. The main engine turbopumps were driven by the gaseous products of decay of the fuel, not those of the oxidizer as is usually the case, After driving the pump, the exhaust stream was directed into the system of non-movable steering nozzles.

Necessary steering control was achieved by changing the rate of exhaust through the corresponding nozzle by the electrically driven gas distribution system. These measures implemented in the second stage design allowed the necessary specific impulse to be reached.

The stage separation systems was almost identical to that of Korolev's R-7 booster. It included an interstage truss structure allowing the ignition and free exhaust for the second stage engine seconds before the first stage separates. The second stage used liquid oxygen as an oxidizer and UDMH as fuel. The underground launch complex Mayak-2 in Kapustin Yar was modified for two-stage 63S1 vehicle.

Kosmos launchers

According to governmental decree, two rockets were assigned for for test launches. The first launch of the vehicle 63S1 No. 1LK with a satellite designated DS-2 (from Russian Dneprovskiy Sputnik) took place on October 26, 1961. The rocket failed due to problems in its flight control system.

The second attempt followed on December 21, 1961. The active flight of the vehicle 63S1 No. 2LK with a DS-2 satellite run smoothly until the engine on the second stage prematurely cut off. Investigation found that the rate at which oxidizer was evaporating inside the stage when warmed up by the engine heat was higher than anticipated. As a result, the propellant was consumed early in flight and the engine was shot down at 353.3 seconds from launch.

It took a special decision by the Minister of Armaments, Dimitry Ustinov, to proceed with further tests. On March 16, 1962, the vehicle 63S1 No. 6LK successfully delivered satellite DS-2 into orbit. The official Soviet press announced the launch as Kosmos-1.

Space operations

Before the end of 1965, the 63S1 rocket successfully launched 22 payloads. By that time, Soviet military also got interested in the launcher for a series of semi-experimental satellites. The special version of the rocket, designated 63SM and the underground launch complex in Kapustin Yar designated "Dvina" were assigned for the program. First test launch took place in October 1965.

At the meantime, the new surface launch complex for the rocket was under construction in Plesetsk. Encoded "Raduga" (Rainbow), it was designed specifically for the Kosmos-2 by Central Design Bureau of Transport Machine Building.

The facility featured a set of unique hardware for handling five types of propellant and three types of gases, including liquid nitrogen and the air heated up to 120°C.

Since the original rocket was developed for silo launches and had low tolerance for surface wind (no more then 10 meters per second), on the launch pad the vehicle was enclosed in a 45-meter-tall service tower on the railroad track. The tower was equipped with service bridges and a crane for handling payloads.

The "Raduga" complex was used for the first time on March 16, 1967 to launch a new version of the booster designated 11K63. Despite four-hour delay due to high winds, a military satellite was successfully launched. It was announced by the USSR as Kosmos-148. During the same year six more rockets were launched with military satellites DS-P1-I, DS-P1-U and DS-Y.

In the following decade, version 11K63 used frequently to launch a variety of military and civilian satellites including highly publicized by the Soviets "Intercosmos" satellites built in cooperation with countries of the eastern block.

The Kosmos-918 was the last satellite launched by the vehicle on June 18, 1977. Since then the booster's role was taken over by more capable 65S3 launch-vehicle based on R-14 missile. Yet, in the open Soviet literature both launch-vehicles were referred as "Kosmos" sometimes creating confusion in the West.


Known specifications of the Kosmos-2 rocket:

Number of stages
Length of the vehicle

30 meters

1,652 meters
Weight (fueled)
49.4 tons
First launch 1961
Launch sites Kapustin Yar, Plesetsk
Stage I
Oxidizer Nitrogen tetroxide, AK-27I
Stage 1 burn time 140 seconds
1st stage propulsion


Stage II
Oxidizer Liquid Oxygen
Stage 2 burn time 260 seconds
2nd stage propulsion



450 kilograms to 200 km orbit




Pre-launch processing of the Kosmos-2 booster. Credit: Roskosmos




Kosmos-2 at liftoff.

Kosmos-2 launcher. Copyright © 2001 Anatoly Zak

The RD-214 engine, which propelled the first stage of the Kosmos-2 booster. Copyright © 2001 Anatoly Zak

The RD-119 engine, which powered the second stage of the Kosmos-2 booster. Copyright © 2001 Anatoly Zak