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Mir complex (Mir base block—Kvant, Kvant 2, and Kristall) with docked

Soyuz-TM and Progress-M spacecraft (as of November 15, 1994)

Length ....................................................... 33 m

Maximum span across habitable

modules .................................................... ~28 m

Maximum diameter of habitable

modules .................................................... 4.35 m

Habitable volume ..................................... 372 m3

Weight ...................................................... 93,649 kg

Orbital inclination .................................... 51.6°

Number of solar arrays ............................. 11

Area of solar arrays .................................. 224 m2

Span across solar arrays ........................... 29.73 m

Electricity available (theoretical

maximum) ................................................ ~27.8 kW

Number of docking/berthing ports ........... 4 docking*; 4 berthing**

Total manned missions ............................. 20

Total long-duration missions .................... 17

*Two of the docking ports are of APAS-89 androgynous design; two are standard Soyuz drogue units. The drogue ports are longitudinal. One is located on the Mir base block and another is at the aft of the Kvant module. The two APAS-89 ports are attached to the node on the lateral end of the Kristall module.

**Two of the four berthing ports (that is, the lateral ports on the Mir base block) are occupied by the Kvant 2 and Kristall modules. However, the two occupied ports can still be freed for use by moving the berthed modules to another lateral berthing port with their Lyappa arms. The existing modules will be shuffled when the Spektr and Priroda modules are added to Mir.

2.9.2 Mir Base Block Detailed Description and Notable Features The conical transfer compartment at the front of the DOS-type Salyut stations is replaced by a five-port docking and berthing node. Four ports are lateral, with their docking planes parallel to the station’s long axis. They are used to berth modules which have docked at the fifth, longitudinal port (the front port). There is no EVA hatch on the Mir base block, though before the arrival of Kvant 2 and Kristall the cosmonauts could egress through any of the five ports. The node is shorter than the Salyut 7 transfer compartment, accounting for Mir’s shorter overall length. The sixth docking port is located at the aft end of the base block. It closely resembles the aft ports on

Salyut 6 and Salyut 7. It is notable because it has been occupied by the Kvant module since April 1987. Electrical connectors and ports for gas and fluids transfers which permitted Progress to service Mir prior to Kvant’s arrival now link Kvant and the Mir base block. Progress vehicles now dock with the aft port on Kvant and transfer fluids and gases through the module to the Mir base block through these ports. The forward longitudinal port of the Mir base block is equipped with ducts for transferring propellant and water from Progress-M supply ships. Gallium arsenide solar arrays produce a 30% increase in power density over Salyut 7’s silicon arrays (to 120 W/m2). The Soviets conducted many gallium arsenide experiments since 1978 on Salyut 6 and Salyut 7. Mir’s arrays have

nearly twice the span of Salyut 7’s arrays. Mir was launched with a fixture on top of its small-diameter pressurized compartment for attachment of an auxiliary solar array. Mir was designed to be used with the Soviet Altair/SR geosynchronous voice and data relay satellites (figure 2-13). These are satellites operated under the ubiquitous Cosmos designation. The satellite system is sometimes designated SDRN (Satellite Data Relay Network) or Luch. A large antenna for radio communications with the Altair/SR system extends from the aft end of Mir. Although most Mir trash is disposed of in the cargo compartments of Progress freighters, Mir, like its DOS-type Salyut predecessors, has a small airlock which can be used for