Soyuz

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THE SOYUZ FAMILY

Soyuz 7K-OK: (1967) Original basic model of Soyuz for earth orbit missions.
Soyuz 7K-OKS: (1971) Modification of Soyuz 7K-OK with a lightweight docking system and a crew transfer tunnel.
Soyuz 7K-T: (1973) Upgraded version of Soyuz following failure of Soyuz-11.
Soyuz 7K-M: (1973) Soyuz ferry as modified for the docking with Apollo.
Progress: (1978) Unmanned space station supply ferry derived from Soyuz.
Soyuz T: (1979) Soyuz T represents a complete redesign of the Soyuz in the late seventies.
Soyuz TM: (1986) Purpose-built for use with Mir and follow-on space stations.
Progress M: (1989) Progress ferry with improved avionics/control and solar panels.


Soyuz is the most-utilized manned spacecraft and is now into its third decade with a flight total comparable to the aggregate for Mercury, Gemini, Apollo and Shuttle. There have also been dozens of umanned orbital tests and it is believed to form the basis of at least one type of photoreconnaissance satellite. Despite its age, Soyuz will continue in its current role as a Mir ferry and has been adopted by NASA as the interim Space Station rescue vehicle. An improved Soyuz-TM will act as the initial ACRV Assured Crew Return Vehicle for the international Space Station.

Chief designer Sergei Korolev intended there to be several Soyuz versions: the full 3-module craft for Earth-orbit operations, a stripped-down 2-module Zond for demonstrating lunar mission techniques, and a lunar-landing orbital version. The spacecraft and missions actually flown fall into three distinct categories. Soyuz 1-9 (1967-69) were configured for 3-man LEO solo missions of up to 2-1/2 weeks. Design work began on the Salyut space station in late 1969 as it became evident the Moon race was lost, and Soyuz 10-11 funtioned as crew ferries with integral transfer tunnels. The Soyuz 11 fatalities during descent prompted a thorough redesign and Soyuz became a 2-man station ferry capable of only 2-1/2 days' independent flight. The unmanned Progress cargo version was also introduced. The new design was launched 24 times in manned configuration and Soyuz 40 retired the model in May-1981. Soyuz-T with its uprated systems and 3-man crews took over for Salyut 7 operations until a further reworking produced the 'TM' Mir ferry, the designation indicating modified transport. Soyuz has thus been transformed from a spacecraft with lunar pretensions to a dedicated space station ferry.

The Soyuz has always had very limited maneuvering capability, a source of some embarrassment during the ASTP joint flight where the Apollo did most of the maneuvering. Not until the Soyuz T version was enough maneuvering fuel and the inertial navigation system available to allow rendezvous with non-cooperative objects (like the dead Salyut 7 station on the epic Soyuz T-15 flight) and to fly around objects for inspection (this is theoretically possible in the old models, but due to limited fuel or conservatism it was never demonstrated).



SOYUZ SPECIFICATIONS

First launch: 23-Apr-1967 Soyuz; 5-Jun-1980 Soyuz-T; 5-Feb-1987 Soyuz-TM
Number manned launches: 37 Soyuz, 14 Soyuz-T, 23 Soyuz-TM (to Feb-1996)
Principal uses: space station ferry, LEO solo operations
Availability: typically 2-4 launched annually
Cost: R95 million (+R56 million for SL-4) quoted in Nov-1992. R5 million quoted during Bulgarian TM5 mission of 1988, plus R4 million for SL-4 launcher
Performance: TM can accommodate a crew of three and 50 kg cargo for Mir-type operations, returning a full crew and 50 kg to Earth (no crew: 450/300 kg up/down). Independent flight time 3.2 days; attached to Mir 180 days. Capabilities are constrained partially by launch escape system. Transported equipment is limited to 45 x 60 x 100 cm up and 30 x 40 x 50 cm down
Principal units: forward Orbital Module (OM), center Descent Module (DM), and aft Service Module (SM)
Overall length: 6.98 m with docking probe withdrawn
Habitable volume: ~10 m3 (T/TM), previously ~9 m3
Launch mass: 7,070 kg (Soyuz-T 6,850 kg). Typically 6,790 kg at docking. Soyuz 19 mass breakdown was 1,224 kg OM, 2,802 kg DM, 2,654 kg SM
Landing mass: about 3,000 kg
Thermal protection: Soyuz-TM's exterior, apart from the SM radiators, is protected by green thermal blanketing; the DM carries eight blankets held by apex + base rings released when the other modules separates. Information on the DM's current re-entry protection is not available
Life support systems: Soyuz is hermetically sealed on the pad under sea level conditions and its 184-263 mbar partial oxygen pressure maintained by regeneration through potassium superoxide and LiOH cylinders. The bulk of the system is housed in the OM but the DM carries a smaller, independent unit. Oxygen bottles provide emergency protection. Waste management and eating is handled entirely in OM; DM offers air sufficient for 48 hours and only food/water packs for landing emergencies. The cosmonauts wear pressure suits.
Avionics/control: the old Soyuz was controlled by ground command and/or pre-programmed analog sequencers activated from switch panels either side of the main display. Soyuz-T introduced the 16 kb-capacity Argon computer, capable of completing a fully automatic rendezvous/docking. Little is known of TM's system but it is believed to have been significantly upgraded and now supported by a backup computer. Attitude information is provided by IR Earth horizon + Sun sensors in conjunction with an improved strapped-down inertial platform. Range/range-rate information is generated by radar deployed on a 2.5 m pylon. Soyuz-TM employs the S-band Kurs docking system that allows it to approach Mir from any angle without the entire station having to rotate, as under the previous Igla system. The commander is aided by the 15o FOV VSK-4 periscope for final approach, together with two external TV cameras

DESCENT MODULE
The decent module carries a single 70 cm diameter overhead hatch, opened from either side, and two 70 cm diameter side hatches for the primary/reserve parachute systems. The DM provides occupants with two 20 cm diameter portholes, one either side of the control panels.
Crew size: 3 (alternately, a 100 kg cargo pod can replace one crewmember)
Length: 2.2 m
Maximum diameter: 2.2 m
Habitable volume: ~4 m3
Total mass: 2,850 kg
Attitude & orbit control system
    thrusters: 6 x 67 N (activated for reentry only)
    propellant: H2O2
L/D hypersonic: 0.25-0.30
Power: small battery supply for power after SM separation
Landing system: On a normal mission, descent is initiated by a 3-4 min ~155 m/s retroburn by the main engine, followed by OM and then SM ejection. The landing system is activated by pressure switch at 9-11 km and 850 km/h, with two sequential stabilizing drogues releasing the 4.25 m braking 'chute from the port compartment. The primary canopy is deployed reefed at 8 km. It is freed to its full 35.5 m diameter at a descent rate of around 35 m/s to reduce sink rate to 8 m/s. The reserve systems yields 10 m/s descent rate with 25 m 'chute, activated at 6 km. The heat shield is dropped at about 3 km some 5 min before landing to clear the base retromotors for a soft landing. Four solids are triggered by a radar altimeter about 2 m above the ground to cushion the impact. Touchdown is normally on land but Soyuz is equipped for water landings

ORBITAL MODULE
The spherodial orbital module (OM) provides space for cargo, food, waste management services, orbital experimentation on solo missions and EVA operations through the 65 cm diameter side hatch. The forward 80 cm hatch houses the docking apparatus inside a 1.3 m diameter docking collar and connections for electrical, communications and hydraulic links. The original Soyuz design included four OM waist portholes, reduced to two on Soyuz-T and one on TM. Since at least 1991, TM has carried at least one front-viewing cupola in the OM, with controls for flyaround operations using direct vision.
Length: 3.0 m
Maximum diameter: 2.2 m
Habitable volume: ~6 m3
Total mass: 1,200 kg

SERVICE MODULE
The service module (SM) supports the DM on its forward face. A 45 cm deep pressurized section houses batteries, power conditioning systems for the twin solar panels and control systems. Umbilicals link this section with the DM's base panel. The unpressurized rear section holds the propulsion system and its four spherical containers; the outer surface provides a mounting for ~8 m2 of thermal radiators.
Length: 2.3 m
Diameter: 2.2 m (flaring to 2.7 m at aft end)
Total mass: 2,700 kg Soyuz / 2,750 kg Soyuz-T / 2,950 kg Soyuz-TM
Propellant mass: 500 kg Soyuz / 700 kg Soyuz-T / 900 kg Soyuz-TM (some 150 kg is reserved for rendezvous/docking, and 200/400 kg is used/allocated for Earth return)
Propulsion system (old Soyuz)
    designation: KTDU-35
    main engine thrust: 4.09 kN vac (+ 4.03 kN backup)
    propellant: nitric acid/UDMH
    specific impulse: 282 s vac
    AOCS thrusters: 14 (+4 backup) x 98 N + 8 (+4 backup) x 9.8 N supplied by H2O2
Propulsion system (Soyuz-T, Soyuz-TM)
    designation: ODU unified propulsion system
    main engine thrust: 3.1 kN vac
    propellant: NTO/UDMH (supplies main engine + AOCS)
    specific impulse: 305 s vac
    AOCS thrusters: 14 x 137 N + 12 x 24.5 N
Power: Soyuz-T introduced twin 4-segment solar wings 1.4 x 4.4 m feeding batteries in the service module. Output ~1.3 kW, with a significant proportion lost in cabling/processing. TM span 10.6 m. Soyuz locks on to the Sun with a sensor and slowly cartwheels around the Sun axis

LAUNCH ESCAPE SYSTEM
The Soyuz launch escape system is activated should anything go wrong on the launch pad or on the ride into orbit. The main events triggering the system include loss of control, premature booster separation, loss of combustion chamber pressure, lack of velocity, and loss of thrust. The system can also be activated from the ground by remote radio control. On activation, three floating struts on the payload fairing fixate to the lower structural ring of the Descent Module to transfer loads from the payload fairing. The main escape motors fire for 2-6 seconds pulling away the top section of the vehicle (including the Descent and Orbital Modules; the Service Module remains with the rocket) and lifting the spacecraft to an altitude of 1-1.5 kilometers. The Descent Module is then disconnected from the fairing and a separation motor fires the capsule away from the bottom of the fairing. A normal landing under parachute follows.
Total mass: 7,635 kg for escape module (escape rocket, fairing, DM and OM)
Maximum thrust: 76 tonnes
G-load on crew: 10 g max. for failure on pad; up to 21 g for failure at T+400 seconds
Separation: 157 s for escape rocket, 161 s for fairing. Escape rocket separation advanced to 123 s for Soyuz-T, 115 s for Soyuz-TM.


PROGRESS SPECIFICATIONS

The constant demand by Salyut and its Mir successor for consumables required the introduction of an unmanned supply ferry. Progress is derived from the manned Soyuz vehicle, but with the descent module replaced by a compartment for transporting up to 940 kg of propellants, other liquids and compressed gases for piping inot the station. The current Progress-M design was introduced in Aug-1989, incorporating Soyuz-TM's Kurs rendezvous/docking system, computer, propulsion unit and solar arrays. The Soyuz orbital module accommodates up to 1,800 kg of removable cargo such as experimental equipment, food, film and air regeneration cylinders. The crew fill this module with unwanted materials and, after Progress has raised its host's orbit to combat atmospheric drag, the ferry is undocked and retrofire ordered over Russia for destructive reentry over the Pacific.
First launch: 20-Jan-1978 Progress; 23-Aug-1989 Progess-M
Number manned launches: 76 to end-1995
Principal uses: unmanned LEO space station ferry
Availability: typically launched every 2-3 months during station occupation
Cost: reported at about R10 million/mission
Performance: up to 2,750 kg total. 1,500-1,800 kg in crew-accessible 7.0 m3 Orbital Module and 940 kg in mid-section (870 kg NTO/UDMH in two spheres each; 50 kg O2). Progress-M can also transfer its own excess propellant. The preceding design carried up to 2,480 kg (up to 1,400 kg in OM + up to 1,200 kg refuelling section)
Overall length: 7.23 m
Launch mass: 7,300 kg; 7,240 kg original Mir design; Salyut variant was 7,020 kg including 2,300 kg cargo
Propulsion: derived from ODU unified propulsion system of Soyuz-T/TM: hypergolic NTO/UDMH is employed with the 3.1 kN main engine and a network of 14 x 98 N (four backup) + 12 x 9.8 N (four backup) thrusters
Power: TM-type solar arrays generating 1.3 kW from 10 m2; batteries carried in pressurized instrument compartment. Augments Mir supply when docked
Avionics/control: Progress M docks with Mir/Kvant's forward or aft port, employing the Kurs approach system. Two external TV cameras are carried and range/range-rate data are transmitted to both mission control and to the space station, who can assist in the docking operation if necessary. Attitude reference provided by Earth horizon sensors + gyro package

RADUGA
Some Progress now deliver a coni-cylindrical reentry capsule among their cargo. Loaded with 80-150 kg of film and samples, the capsule is mounted in Progress' hatch by the crew and released after retrofire by the ferry at about 120 km for recovery by parachute.
Length: 1.40 m
Cargo volume: 0.160 m3
Total mass: 350 kg (168 kg without payload and 0-30 kg balance mass)
Landing system: braking chute deploy barometrically at 15.5 ±2.5 km (Mach 1.5 ±0.5); main chute 5.6 m diameter. Antennas on chute lines and cloud of dipole reflectors released. Balloon provides buoyancy for water landings


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