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Article Number: 11F639. Class: Communications. Destination: Geosynchronous Orbit. Nation: Russia. Agency: Various. Manufacturer: Reshetnev. The Ekspress series communications satellite closely resembled the Gals spacecraft and shared a similar spacecraft bus. Ekspress replaced the Gorizont spacecraft, with deployment to 13 geosynchronous positions beginning in 1994 and continuing beyond 2005. Nine months after Gals 1 was launched, Ekspress 1 was inserted into a nearly geosynchronous orbit. Ekspress was to replace the widely used Gorizont spacecraft, and plans called for deployments at 13 locations (40 degrees , 53 degrees , 80 degrees , 90 degrees , 96.5 degrees , 99 degrees , 103 degrees , 140 degrees , 145 degrees , 205 degrees , 322.5 degrees , 346 degrees , and 349 degrees , all East longitude) just for domestic needs and to support the Intersputnik Telecommunications Association. Additional Ekspress spacecraft were to be sold to foreign companies, e.g., Rimsat, Ltd. In fact, only the first two satellites launched was of the original configuration. Further state-sponsored launches were not funded, however a total of 12, many heavily modified and with European electronics packages, were launched through 2005.
While the Express solar arrays were identical to those on Gals, the spacecraft bus had slightly smaller dimensions of 3.6 m by 6.1 m. A typical Ekspress payload included 10 C-band and two Ku-band transponders. The improved Ekspress-A model was launched from 1999.
The improved Express-AM-1 satellite first flew in 2004 and was produced by Reshetnev NPO PM jointly with NEC/Toshiba Space Systems for the Russian Satellite Communications Company. The satellite was designed to provide a package of communications services (digital TV, telephony, video conferencing, data transmission, the Internet access) and to deploy satellite networks by applying VSAT technology. The Express-AM spacecraft was equipped with up-to-date antenna systems, to provide high-quality communications and uniform coverage in C- and Ku- bands.
Satellite characteristics
- Orbit Geostationary
- Station keeping accuracy ±0,05° (N&S / E&W)
- Operational life-time 12 years
- Stabilization Three axes
- Payload electric power 4200 W
- Mass of payload 570 kg
- Mass of satellite 2600 kg
- Power supply 6000 W
- Transponder parameters:
- C-band: 9 transponders; bandwidth at -1dB, 40 MHz; output power, 40 W (8 transponders), 120 W (1 transponder)
- Ku-band:18 transponders, bandwidth at -1dB, 54 MHz; output power 95-100 W
- L-band: 1 transponder; bandwidth at -1dB, 0,5 MHz; output power, 30 W
Design Life: 7 years. Typical orbit: 35777 km x 35794 km at 0 degrees inclination. Mass: 2,500 kg (5,500 lb). Associated Launch Vehicle: Proton 8K82K / 11S861-01.
Ekspress Chronology
- 2000 April 17 - Sesat - Launch Site: Baikonur. Launch Vehicle: Proton 8K82K / 11S861-01. Mass: 2,500 kg (5,500 lb). Perigee: 35,772 km (22,227 mi). Apogee: 35,800 km (22,200 mi). Inclination: 0.00 deg.
Sesat (Siberia-Europe Satellite) used an MSS-2500-GSO (Gals/Ekspress) satellite bus built by NPO PM of Krasnoyarsk, with an Alcatel Espace France payload of 18 Ku-band transponders. The satellite had 8 Fakel SPD-100 plasma thrusters for stationkeeping. Eutelsat operated their Hot Bird fleet of European television broadcast satellites since the 1980's, but the venture into broadcasting to Siberia represented a new step for them. Stationed at 36 deg E. Positioned in geosynchronous orbit at 39 deg E in 2000. As of 4 September 2001 located at 35.97 deg E drifting at 0.005 deg E per day. As of 2007 Mar 9 located at 35.92E drifting at 0.004E degrees per day.
- 2000 March 12 - Ekspress 6A - Launch Site: Baikonur. Launch Vehicle: Proton 8K82K / 11S861-01. Mass: 2,600 kg (5,700 lb). Perigee: 35,776 km (22,230 mi). Apogee: 35,798 km (22,243 mi). Inclination: 0.00 deg.
GO Kosmicheskaya Svyaz geosynchronous communications satellite, to be assigned to the Ekspress 6A slot at 80E. Replaced the first Ekspress A, lost in a launch failure in 1999. Russian satellite bus with a ommunications payload from Alcatel France. Stationed at 80 deg E. Positioned in geosynchronous orbit at 80 deg E in 2000. As of 5 September 2001 located at 80.02 deg E drifting at 0.008 deg W per day. As of 2007 Mar 10 located at 102.77E drifting at 0.018W degrees per day.
- 2002 June 10 - Ekspress A1R - Launch Site: Baikonur. Launch Vehicle: Proton 8K82K / 11S861-01. Mass: 2,600 kg (5,700 lb). Perigee: 35,776 km (22,230 mi). Apogee: 35,792 km (22,240 mi). Inclination: 0.20 deg. Period: 1,436.00 min.
Launch delayed from May 2002. The Ekspress A1R Russian domestic communications satellite was built by NPO PM and Alcatel for Kosmicheskiya Svyaz, the Russian satcom operator. The Proton's parking orbit was off-nominal but the 11S861-01 Blok DM-2M upper stage corrected for this and delivered the payload to the correct orbit. Parking orbit was about 180 x 185 km x 51.6 deg; transfer orbit after the first DM-2M burn was 328 x 36133 km x 47.4 deg; orbit at spacecraft separation was 36102 x 36171 km x 0.2 deg. Two SOZ ullage motors were left in the transfer orbit. As of 2007 Mar 10 located at 14.07W drifting at 0.008W degrees per day.
- 2004 October 29 - Ekspress AM-1 - Launch Site: Baikonur. Launch Vehicle: Proton 8K82K / 11S861-01. Mass: 2,542 kg (5,604 lb). Perigee: 35,783 km (22,234 mi). Apogee: 35,792 km (22,240 mi). Inclination: 0.10 deg. Period: 1,436.10 min.
Russian Satellite Communications Company spacecraft, to be stationed at 40 deg E, providing 28 C, Ku, and L band transponders for a wide range of communications and data services. The Ekspress-AM uses an improved Ekspress-M or 727M bus, first used on the Sesat satellite, while the earlier models used the KAUR-4 MSO-2500 bus. As of 2007 Mar 10 located at 39.98E drifting at 0.006W degrees per day.
- 2005 March 29 - Ekspress AM-2 - Launch Site: Baikonur. Launch Vehicle: Proton 8K82K / 11S861-01. Mass: 2,600 kg (5,700 lb). Perigee: 35,773 km (22,228 mi). Apogee: 35,893 km (22,302 mi). Inclination: 0.10 deg. Period: 1,438.50 min.
Delayed from December 2004, then moved up from March 31, 2005. Communications payload of C, Ku and L band transponders. It was to be stationed at 80 deg E. As of 2007 Mar 10 located at 80.01E drifting at 0.008W degrees per day.
Bibliography and Further Reading - Vladimirov, A, Novosti kosmonavtiki, "Tablitsa zapuskov RN 'Proton' i 'Proton K'", 1998, Issue 10, page 25.
- McDowell, Jonathan, Jonathan's Space Home Page, Harvard University, 1997-present. Jonathan McDowell's complete on-line listing of all objects orbited and over 20,000 rocket launches Accessed at: http://www.planet4589.org/jsr.html.
- McDowell, Jonathan, Jonathan's Space Report (Internet Newsletter), Harvard University, Weekly, 1989 to Present. Essential internet newsletter recording worldwide weekly space events. Accessed at: http://www.planet4589.org/jsr.html.
- Kaesmann, Ferdinand, et. al., Journal of the British Interplanetary Society, "Proton - Development of A Russian Launch Vehicle", 1998, Volume 51, page 3.
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