The Soyuz TMA spacecraft is designed to serve as the International Space Station's crew return vehicle, acting as a lifeboat in the unlikely event an emergency would require the crew to leave the station. A new Soyuz capsule is normally delivered to the station every six months.

The Soyuz spacecraft is launched to the space station from the Baikonur Cosmodrome in Kazakhstan aboard a Soyuz rocket. It consists of an Orbital Module, a Descent Module and an Instrumentation/Propulsion Module.

The Orbital Module of the Soyuz spacecraft is used by the crew while on orbit during free-flight. It has a volume of 6.5 cubic meters (230 cubic feet), with a docking mechanism, hatch and rendezvous antennas located at the front end. The docking mechanism is used to dock with the space station and the hatch allows entry into the station. The rendezvous antennas are used by the automated docking system — a radar-based system — to maneuver towards the station for docking. There is also a window in the module.

The opposite end of the Orbital Module connects to the Descent Module via a pressurized hatch. Before returning to Earth, the Orbital Module separates from the Descent Module — after the deorbit maneuver — and burns up upon re-entry into the atmosphere.

Exclusively for SA, Elro creates an interactive 3D Soyuz animation

The Descent Module is where the crew sits for launch, re-entry and landing. All the necessary controls and displays of the Soyuz are located here. The module also contains life support supplies and batteries used during descent, as well as the primary and backup parachutes and landing rockets. It also contains custom-fitted seat liners for each crewmember's couch/seat, which are individually molded to fit each person's body — this ensures a tight, comfortable fit when the module lands on the Earth.

The module has a periscope, which allows the crew to view the docking target on the station or the Earth below. The eight hydrogen peroxide thrusters located on the module are used to control the spacecraft's orientation, or attitude, during the descent until parachute deployment. It also has a guidance, navigation and control system to maneuver the vehicle during the descent phase of the mission.

This module weighs 2,900 kilograms (6,393 pounds), with a habitable volume of 4 cubic meters (141 cubic feet). Approximately 50 kilograms (110 pounds) of payload can be returned to Earth in this module. The Descent Module is the only portion of the Soyuz that survives the return to Earth.

This module contains three compartments: Intermediate, Instrumentation and Propulsion.

The intermediate compartment is where the module connects to the Descent Module. It also contains oxygen storage tanks and the attitude control thrusters, as well as electronics, communications and control equipment. The primary guidance, navigation, control and computer systems of the Soyuz are in the instrumentation compartment, which is a sealed container filled with circulating nitrogen gas to cool the avionics equipment. The propulsion compartment contains the primary thermal control system and the Soyuz radiator, which has a cooling area of 8 square meters (86 square feet). The propulsion system, batteries, solar arrays, radiator and structural connection to the Soyuz launch rocket are located in this compartment.

The propulsion compartment contains the system that is used to perform any maneuvers while in orbit, including rendezvous and docking with the space station and the deorbit burns necessary to return to Earth. The propellants are nitrogen tetroxide and unsymmetric-dimethylhydrazine. The main propulsion system and the smaller reaction control system, used for attitude changes while in space, share the same propellant tanks.

The two Soyuz solar arrays are attached to either side of the rear section of the Instrumentation/Propulsion Module and are linked to rechargeable batteries. Like the Orbital Module, the intermediate section of the Instrumentation/Propulsion Module separates from the Descent Module after the final deorbit maneuver and burns up in atmosphere upon re-entry.

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A Soyuz spacecraft generally takes two days after launch to reach the space station. The rendezvous and docking are both automated, though once the spacecraft is within 150 meters (492 feet) of the station, the Russian Mission Control Center just outside Moscow monitors the approach and docking. The Soyuz crew has the capability to manually intervene or execute these operations.

The Soyuz TMA spacecraft is a replacement for the Soyuz TM, which was used from May 1986 to November 2002 to take astronauts and cosmonauts to Mir and then to the International Space Station beginning in November 2000.

The TMA increases safety, especially in descent and landing. It has smaller and more efficient computers and improved displays. In addition, the Soyuz TMA accommodates individuals as large as 1.9 meters (6 feet, 3 inches tall) and 95 kilograms (209 pounds), compared to 1.8 meters (6 feet) and 85 kilograms (187 pounds) in the earlier TM. Minimum crewmember size for the TMA is 1.5 meters (4 feet, 11 inches) and 50 kilograms (110 pounds), compared to 1.6 meters (5 feet, 4 inches) and 56 kilograms (123 pounds) for the TM.

Two new engines reduce landing speed and forces felt by crewmembers by 15 to 30 percent and a new entry control system and three-axis accelerometer increase landing accuracy. Instrumentation improvements include a color "glass cockpit," which is easier to use and gives the crew more information, with hand controllers that can be secured under an instrument panel. All the new components in the Soyuz TMA can spend up to one year in space.

New components and the entire TMA were rigorously tested on the ground, in hangar-drop tests, in airdrop tests and in space before the spacecraft was declared flight-ready. For example, the accelerometer and associated software, as well as modified boosters (incorporated to cope with the TMA's additional mass), were tested on flights of Progress unpiloted supply spacecraft, while the new cooling system was tested on two Soyuz TM flights.

Descent module structural modifications, seats and seat shock absorbers were tested in hangar drop tests. Landing system modifications, including associated software upgrades, were tested in a series of airdrop tests. Additionally, extensive tests of systems and components were conducted on the ground.

The Space Adventures orbital spaceflight program uses the Soyuz-TMA spacecraft.

Other Space Adventures programs offer training in Soyuz simulators, such as Orbital Pre-Qualification [link to 2.1] and the Soyuz Simulator Program [link to 3.10].

Up to three crewmembers can return from the International Space Station aboard a Soyuz TMA spacecraft. The vehicle lands on the flat steppes of Kazakhstan in central Asia. A Soyuz trip to the station takes two days from launch to docking, but the return to Earth takes less than 3.5 hours.

The Soyuz TMA spacecraft is composed of three elements attached end-to-end — the Orbital Module, the Descent Module and the Instrumentation/Propulsion Module. The crew occupies the central element, the Descent Module. The other two modules are jettisoned prior to re-entry. They burn up in the atmosphere, so only the Descent Module returns to Earth.

The Soyuz commander can pilot the module using a rotational hand controller that manages the firing of eight hydrogen peroxide thrusters on the vehicle's exterior. This system is deactivated 15 minutes before landing, when the parachutes are deployed.

Having shed two-thirds of its mass, the Soyuz reaches Entry Interface — a point 121,920 meters (400,000 feet) above the Earth, where friction due to the thickening atmosphere begins to heat its outer surfaces — three hours after undocking. With only 23 minutes left before it lands on the grassy plains of central Asia, attention in the module turns to slowing its rate of descent.

Eight minutes later, the spacecraft is streaking through the sky at a rate of 230 meters (755 feet) per second. Before it touches down, its speed will slow to only 1.5 meters (5 feet) per second, and it will land at an even lower speed than that. Several onboard features ensure that the vehicle and crew land safely and in relative comfort.

Four parachutes, deployed 15 minutes before landing, dramatically slow the vehicle's rate of descent. Two pilot parachutes are the first to be released, and a drogue chute attached to the second one follows immediately after. The drogue, measuring 24 square meters (258 square feet) in area, slows the rate of descent from 230 meters (755 feet) per second to 80 meters (262 feet) per second.

The main parachute is the last to emerge. It is the largest chute, with a surface area of 1,000 square meters (10,764 square feet). Its harnesses shift the vehicle's attitude to a 30-degree angle relative to the ground, dissipating heat, and then shift it again to a straight vertical descent prior to landing.

Less than four hours after undocking from the International Space Station, the Soyuz spacecraft returns to Earth in Kazakhstan.

The main chute slows the Soyuz to a descent rate of only 7.2 meters (24 feet) per second, which is still too fast for a comfortable landing. One second before touchdown, two sets of three small engines on the bottom of the vehicle fire, slowing the vehicle to soften the landing.

Further cushioning the impact of landing are the crew seats with their custom-fitted liners. The liners are made preflight, individually molded to fit each person's body — this ensures a tight, comfortable fit when the module lands on the Earth. When crewmembers are brought to the station aboard the space shuttle, their seat liners are delivered with them and transferred to the existing Soyuz spacecraft as part of crew handover activities.

Soyuz TMA seats accommodate both larger and smaller occupants than the older model, and seat shock absorbers have been modified to suit the varying loads.

The Soyuz TMA spacecraft is a replacement for the Soyuz TM, which was used from May 1986 to November 2002 to take astronauts and cosmonauts to Mir and then to the International Space Station beginning in November 2000.

The TMA increases safety, especially in descent and landing. Two new engines reduce landing speed and forces felt by crewmembers by 15 to 30 percent, and a new entry control system and three-axis accelerometer increase landing accuracy. Instrumentation improvements include a color "glass cockpit," which is easier to use and gives the crew more information, with hand controllers that can be secured under an instrument panel. All the new components in the Soyuz TMA can spend up to one year in space.

Descent module structural modifications, seats and seat shock absorbers were tested in hangar drop tests. Landing system modifications, including associated software upgrades, were tested in a series of airdrop tests. Additionally, extensive tests of systems and components were conducted on the ground.