Ekspress (satellite bus)

The Еkspress (Russian: Экспресс) is a highly flexible satellite bus designed and manufactured by ISS Reshetnev. It is an unpressurized bus originally designed for GEO, but that has been adapted for medium Earth orbit and to highly elliptical orbit. It has different versions and has been used from civilian communications to satellite navigation.

The Ekspress bus has two main platforms: the 1000 light to medium version and the 2000, for heavy birds. There was a project for a third platform, the 4000, but it has never been used, yet.

The Ekspress-1000 (Russian: Экспресс-1000) in its different variations offers an platform for small to medium satellites. It is a direct to GEO bus for total spacecraft weights from 1,200 kg (2,600 lb) to 2,200 kg (4,900 lb) and having a power production from 3 kW to 8 kW with a life expectancy of 15 years. It is designed for directly stacking up to 3 of the smallest version (Ekspress-1000K) or 2 of the bigger ones.

The Ekspress-2000 (Russian: Экспресс-2000) is the fruits of the collaboration with Thales Alenia Space and their Spacebus 4000 experience with the Еkspress-1000H. It is a big platform for spacecraft massing up to 3,500 kg (7,700 lb), with space for 1,000 kg (2,200 lb) of payload and up to 14 kW of power generation and 7.5 kW of heat dissipation. It is, as the rest of the family, a direct to GEO bus and given its size it is not designed to be stacked. It has an expected design life of 15 years.

The Ekspress-4000 (Russian: Экспресс-4000) is a collaboration with Thales Alenia Space to mix the best elements of the Ekspress-2000 with the Spacebus 4000. It would be a direct to GEO platform for spacecrafts massing up to 3,200 kg (7,100 lb) and having a power production of 14 kW with a life expectancy of 15 years. This would enable more than 60 transponders of payload.

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Wikipedia