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Origin of the Soyuz spacecraft

Conceived in 1960, the Soyuz spacecraft became the second-generation Soviet vehicle capable of carrying humans into space. Unlike its predecessor -- a one-seat Vostok -- the Soyuz would be able to conduct active maneuvering, orbital rendezvous and docking. These capabilities were all necessary for a flight around the Moon and to support lunar landing. In the early scenario of a "circumlunar" mission, defined in 1962, the Soyuz complex would be assembled in the low-Earth orbit out of three consecutively launched elements.

7K-OK: Original Soyuz

Compared to its predecessors -- Vostok and Voskhod -- the three-seat Soyuz offered enormous advantages. The most important feature of the new ship would be its rendezvous and docking system.


Origin of 7K-OK variant

Despite its roots in the Soviet lunar exploration effort, the first Soyuz spacecraft to reach space was intended for missions in the Earth's orbit. Designated 7K-OK, its main goal was the rehearsal of orbital rendezvous, which would be crucial for a lunar expedition. Missions of Soyuz 7K-OK also had the political goal of shortening the hiatus in the Soviet human space flight program.


Development of 7K-OK

On August 28, 1965, the leading designer Aleksei Topol brought Boris Chertok the official schedule for the development of 7K-OK, which had just been approved by Korolev. Chertok could hardly believe his eyes, because by December of the same year, the document required to build and outfit Soyuz prototypes for 13 different tests.


Production of early Soyuz spacecraft

In the second half of 1965, after several years on a drawing board, the USSR’s new-generation manned spacecraft started appearing in metal. The final assembly of the Soyuz was centered at Hall 44, led by G.M. Markov, at the Experimental Machine-building Plant, ZEM, in Podlipki, which traditionally served as the manufacturing base for the adjacent OKB-1 design bureau.

7K-OK No. 2 (Kosmos-133)

On November 28, 1966, the USSR launched the first test mission of the new-generation Soyuz spacecraft under a cover name of Kosmos-133. The unmanned vehicle was expected to play a role of the "active" ship during rendezvous maneuvers with a "passive" spacecraft scheduled for launch 24 hours later. However things did not go according to plan...
No. 1

7K-OK No. 1 launch attempt

Hoping to recover quickly from major technical problems in the maiden mission of Soyuz on Nov. 28, 1966, Soviet engineers rushed to prepare the launch of the second spacecraft remaining from the aborted dual flight. With a much better understanding of technical and organizational challenges, leaders of the Soyuz project decided to send the 7K-OK No. 1 vehicle on a solo mission on December 14, 1966. However this time, the launch attempt brought a fatal disaster...

NEW: 7K-OK No. 3 (Kosmos-140)

The third unmanned test launch of the Soyuz spacecraft aimed to finally deliver a clean performance of the new vehicle and thus open the door for the resumption of the politically important manned space flight in the USSR after a two-year hiatus. The mission lifted off in February 1967 and could be considered a resounding success for the new-generation spacecraft... if not for a nasty surprise at the very end of the flight...


Tragic mission of Soyuz-1

The first manned launch of the Soyuz spacecraft on April 23, 1967, ended catastrophically 24 hours later with the loss of Vladimir Komarov in crash landing due to failure of the main parachute to deploy.

In-depth: Planning | Scenario | Training | Preparing | Decision | Launch | Reentry | Crash | Investigation


7K-L3 (LOK): Soyuz for the Moon

In parallel with the development of the 7K vehicle, the Soviet designers worked on a spacecraft designated LOK -- essentially the Soyuz "on steroids," which would be capable of carrying two Soviet cosmonauts into orbit around the Moon. During expeditions on the lunar surface, LOK would play a role of the "mother" spacecraft for the LK lander, which would deliver one crewmember on the surface of the Moon.


NEW: L1: Around the Moon

An "abbreviated" version of the Soyuz spacecraft, designated L1, was developed for a circumlunar mission launched by the Proton rocket. Officially identified as Zond, the L1 spacecraft was essentially the Soyuz, minus a habitation module. Several L1 vehicles flew unmanned, with mixed results; however the program was ultimately canceled, as it fell behind American Apollo missions.

7K: Soyuz for the station

With the end of the Moon Race, the USSR quietly shifted its focus in manned spaceflight to the Earth-orbiting station. Accordingly, the Soyuz was re-tailored for the role of a ferry, capable of delivering a crew of three to the orbital outpost. The first such vehicle, designated Soyuz-10, flew in 1971. However the same year, mission of Soyuz-11, ended in disaster, when its three cosmonauts died as a result of a decompression of their reentry capsule on the way home. In the wake of the catastrophe, the crew size onboard Soyuz was reduced to two to save weight for the protective pressure suits and related safety gear onboard.


Soyuz 7K-TM: Soyuz-Apollo

A specialized version of the Soyuz spacecraft originally known as 7K-TM was custom-designed for the joint mission with the US Apollo spacecraft in 1975. It was equipped with a new type of a docking port dubbed APAS.


Soyuz T: Transport

Inaugurated in 1978, the Soyuz T spacecraft, (T stands for "transport") featured a brand-new motion control system, using a digital computer; a modified propulsion system with an integrated fuel supply system for all engines. Many onboard systems were replaced with newer, better ones. Combined, these modifications allowed to increase the size of the crew back to three, this time pressure suits included. The orbital lifespan of the spacecraft was also increased. In 1980, the Soyuz T carried crew into orbit for the first time.

Soyuz TM: Modified

The TM modification of the Soyuz spacecraft, where M stands for "modified," sported the Kurs advanced rendezvous radio system, modified motion control system and radio communication system. It was also equipped with a thruster assembly with segmented propellant and gas stores. The vehicle was launched for the first time unmanned in 1986 toward the Mir space station, and carried its first crew to Mir in 1987. The TM version also became a base for the Progress M series of cargo carriers.

Soyuz ACRV

Bigger Soyuz

In October 1991, during a meeting with Boeing representatives (the main station contractor) the head of NPO Energia Yuri Semenov offered the company's Soyuz spacecraft to serve as a "lifeboat" for Space Station Freedom. On June 18, 1992, NASA Administrator Daniel Goldin and Director General of the Russian Space Agency Yuri Koptev "ratified" a contract between NASA and NPO Energia to study possible use of Soyuz and Russian docking port in the Freedom project.

Soyuz TMA: Anthropometric

The Soyuz TMA, or "anthropometric" version was designed within US-Russian cooperative program on the International Space Station, ISS. "Anthropometric" upgrades mostly aimed to allow taller crewmembers to fly the Soyuz. The production of the TMA spacecraft, however, was stalled by non-payments by the Russian government to the RKK Energia at the end of the 1990s. Ironically, NASA, which originally ordered the upgrades, at one point, refused to pay for the development of the TMA, until Russia could ensure the future production of the spacecraft. After many delays, the TMA finally flew in 2002.

Soyuz TMA-M

TMA-M: "Digital" Soyuz

The introduction of the Soyuz TMA-M spacecraft became the latest step in a series of gradual upgrades to Russia's legendary manned transport. Originally designated as Series 700, Soyuz TMA-M was also informally known as "digital Soyuz," -- a reference to an advanced flight control computer onboard. Systems introduced in this round of modifications also promised to pave the way to the development of the new-generation manned vehicle. After some delays, the first Soyuz TMA-M made it to the launch pad in October 2010.

sep NEW, July 8: Soyuz MS: The ultimate upgrade?

After nearly half a century of orbital missions, the Russian veteran transport spacecraft got another upgrade in 2016 with the Soyuz-MS variant (also know as Series 730). Soyuz MS replaced Soyuz TMA-M.

In depth: Kurs-NA rendezvous system | Power supply system | EKTS satellite communications system | Propulsion system | SZI-M "Black box"

Soyuz ACTS: Back to the Moon

The Advanced Crew Transportation System, ACTS, also known as "Euro-Soyuz," emerged during 2006, when Russian company RKK Energia realized that its proposals to replace the Soyuz spacecraft with the Kliper reusable glider would be too ambitious for the current level of funding of the Russian space industry. Instead, a modified Soyuz, with the capability of reaching lunar orbit, would serve as a technological bridge, possibly paving the way to the future development of the Kliper.

After tomorrow: Lunar tug

In mid-2000s, improving economic outlook for the Russian economy and slowly growing space budget perhaps encouraged RKK Energia to dust off its old plans for building a lunar base. One concept for a lunar transport would include a combination of a Soyuz-derived reentry vehicle with the large habitation section, based on the cabin module of a proposed Kliper reusable orbiter.

Systems Design overview

A classic seven-ton Soyuz vehicle consists of three major components, providing for every stage of flight from orbital insertion to landing. To protect the ship's systems from extreme temperature swings in space, all its surfaces exposed to space, except for active elements of sensors, antennas, windows, the docking hardware, thruster nozzles and radiator panels, are blanketed in multilayer vacuum-screen thermal insulation.

BO Habitation section (BO)

The habitation section of the Soyuz spacecraft, carries crucial life-support systems for the crew, including toilet and water supplies. It also provides extra habitation room during the flight and can serve as an airlock for space walks. In most missions, the front end of the habitation section is equipped with docking hardware, allowing the crew to remain

SA Reentry capsule (SA)

The reentry capsule of the Soyuz spacecraft, known by its Russian acronym as "SA." is the only section of the vehicle, which returns to Earth at the end of the mission. It contains two or three personally contoured couches where the cosmonauts recline for ascent, descent and landing. Seats are facing controls and displays used for all critical flight activities.

PAO Service module (PAO)

The instrument module of the Soyuz spacecraft, known by its Russian acronym as PAO, or Priborno-Agregatniy Otsek, in its turn is subdivided into three main sections: Intermediate compartment, Instrumentation compartment, PO, and Propulsion compartment, AO.


Soyuz mission overview

From 1971 and well into the 21st century, the Soyuz spacecraft's main role in the Russian space program was to deliver crews to space stations in the low-Earth orbit. The Soyuz could remain in space up to 200 days, when docked to the station and it could orbit the Earth in the autonomous flight for 4.2 days. The autonomous flight would normally be split into two phases: a 2.2-day period spent from launch to docking with the station, and a several-hour long period from undocking to landing with a built-in reserve of two days.


How Soyuz is launched

For almost half a century, the manned Soyuz spacecraft has ridden into orbit on top of its namesake rocket. Over the decades, the spacecraft and its launch vehicle went through several upgrades, however the launch profile had not changed much. Spent stages of the rocket and other components fall into several designated areas in Kazakhstan and in Russia minutes after their separation.


Emergency escape system

For decades, rockets have remained the fastest and most dangerous mode of transportation created by humans. Not surprisingly, engineers went to great lengths to develop "insurance policies" in case something goes wrong during a wild ride beyond the Earth atmosphere. As it turned out, the most practical way of escaping from a failing rocket would be to use yet another dedicated rocket! Such method was used on American Mercury, Apollo and Russian Soyuz. The latter system had actually got a chance to prove itself in real life emergency situation...


Docking system

The docking was the primary capability of the Soyuz spacecraft during both lunar landing program and numerous space station missions that followed. Several types and reincarnations of the docking hardware were tested between 1967 and 1975, before a long-lived design of the "drog-and-cone system" has emerged. Such mechanism involves a rod on the Soyuz spacecraft, which serves as an active spacecraft during the rendezvous, and a receptive cone, installed onboard the space station.