The Soyuz succeeded the Voskhod spacecraft and was originally built as part of the Soviet crewed lunar programs.

Following the Soviet Union's dissolution, Roscosmos, the Russian space agency, continued to develop and utilize the Soyuz.

The Soyuz design has also influenced other spacecraft, including China's Shenzhou and Russia's Progress cargo vehicle.

The program suffered another fatal setback during Soyuz 11, where cabin depressurization during reentry killed the entire crew.

[1] Despite these early tragedies, Soyuz has earned a reputation as one of the safest and most cost-effective human spaceflight vehicles, a legacy built upon its unparalleled operational history.

Soyuz spacecraft are composed of three primary sections (from top to bottom, when standing on the launch pad): The orbital and service modules are discarded and destroyed upon reentry.

This design choice, while seemingly wasteful, reduces the spacecraft's weight by minimizing the amount of heat shielding required.

The Vostok spacecraft used an ejector seat to bail out the cosmonaut in the event of a low-altitude launch failure, as well as during reentry; however, it would probably have been ineffective in the first 20 seconds after liftoff, when the altitude would be too low for the parachute to deploy.

This included developing a complex sensing system to monitor various launch-vehicle parameters and trigger an abort if a booster malfunction occurred.

The only modification was in 1972, when the aerodynamic fairing over the SAS motor nozzles was removed for weight-saving reasons, as the redesigned Soyuz 7K-T spacecraft carried extra life-support equipment.

The uncrewed Progress resupply ferry has a dummy escape tower and removes the stabilizer fins from the payload shroud.

[8] Most recently, in 2018, the SAS sub-system in the payload shroud of Soyuz MS-10 successfully rescued the cosmonauts from a rocket failure 2 minutes and 45 seconds after liftoff, after the escape tower had already been jettisoned.

The forepart of the spacecraft is the orbital module (Russian: бытовой отсек, romanized: bytovoi otsek), also known as habitation section.

The convention of orientation in a micro-g environment differs from that of the descent module, as crew members stand or sit with their heads to the docking port.

This change was made as the TM-5 crew could not deorbit for 24 hours after they jettisoned their orbital module, which contained their sanitation facilities and the docking collar needed to attach to Mir.

The descent module (Russian: Спуска́емый Аппара́т, romanized: spuskáyemy apparát), also known as a reentry capsule, is used for launch and the journey back to Earth.

At one meter above the ground, solid-fuel braking engines mounted behind the heat shield are fired to give a soft landing.

One of the design requirements for the descent module was for it to have the highest possible volumetric efficiency (internal volume divided by hull area).

VIM low-density silica fibrous insulation (8mm thick) is contained in the gap between the heat shield ablator and aluminum substrate.

The spacecraft is turned engine-forward, and the main engine is fired for deorbiting on the far side of Earth ahead of its planned landing site.

[citation needed] Later Soyuz spacecraft detached the orbital module before firing the main engine, which saved propellant.

The Soyuz 7K-L1 was designed to launch a crew from the Earth to circle the Moon, and was the primary hope for a Soviet circumlunar flight.

Soyuz 1 was plagued with technical issues, and cosmonaut Vladimir Komarov was killed when the spacecraft crashed during its return to Earth.

The fourth generation Soyuz-TM spacecraft, where the "M" stands for "modified" (Russian: модифицированный, romanized: modifitsirovannyi), were used from 1986 to 2002 for ferry flights to Mir and the International Space Station (ISS).

The Soyuz TMA spacecraft, where the "A" stands for "anthropometric" (Russian: антропометрический, romanized: antropometricheskii), features several changes to accommodate requirements requested by NASA in order to service the International Space Station (ISS), including more latitude in the height and weight of the crew and improved parachute systems.

Soyuz-TMA looks identical to a Soyuz-TM spacecraft on the outside, but interior differences allow it to accommodate taller occupants with new adjustable crew couches.

The Soyuz TMA-M was an upgrade of the Soyuz-TMA, using a new computer, digital interior displays, updated docking equipment, and the vehicle's total mass was reduced by 70 kilograms.

While the Shenzhou is not a direct derivative of the Soyuz, it incorporates significant technology and design elements from the spacecraft because of the collaboration.