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On October 13, 1994, Russia launched the first Express satellite, (officially designated Express-2) representing a new generation of spacecraft designed to boost the capacity of the country's satellite communications networks. The new system would replace obsolete Gorizont satellites, which had been in use since 1979. The original network of Express satellites developed by NPO PM in Zheleznogorsk was designed to provide an array of traditional communication services:
The 2.5-ton spacecraft would carry nine antennas and 12 transponders and it was designed to last between five and seven years. The satellite bus would be equipped with a flight control computer and plasma thrusters for orbital correction, which would enable it to maintain its altitude with the accuracy of 0.2 degrees. Along with the Gals spacecraft, the Express would be capable to maintain not only its longitudinal position over the Equator but the inclination of its orbit. The Express spacecraft would support the same communications networks that were previously serviced by the Gorizont satellites, including TV Moskva system. Thanks to more powerful hardware onboard Express, the diameter of ground antennas targeting the satellite could be reduced from 4.5 meters to 2.5 meters. (126) Russia planned several positions on the geostationary orbit with following coordinates for the Express birds: 14 and 11 degrees West, 40, 53, 80, 90, 96.5, 103, 140 and 145 East longitude. (204) Although as many as 13 spacecraft had been planned for launch, only the second spacecraft -- Express-6 -- made it to orbit on Sept. 26, 1996, before a new round of upgrades to its communication payload was required. Express mods During 1990s, NPO PM proposed a number of upgrades to the Express spacecraft with ever increasing power and communication capacity. The Express-M series was proposed around 1993, however project could not be funded in the wake of Russia's financial problems. In the second half of the 1990s, NPO PM proposed Express-A, -K1, -K2, K3 series of satellites, which would be developed in parallel and launched between 1999 and 2002, gradually building up the communication capacity, power and life span. The company also sought Western subcontractors to develop more reliable and powerful communication payloads for its next-generation satellites. Express-A The first upgraded satellite, designated as Express-A1, and carrying communication payload build by Alcatel of France, reached the launch pad in 1999, more than three years, after the last spacecraft from the original Express series was launched. It was scheduled to take orbital position of 80 degrees East over the Equator replacing the ailing Express-6. Express-A1 had 12 Alcatel-built transponders, while Express 6 (No. 12) has 10 C-band operational transponders. However minutes after the launch on October 27, 1999, second stage of the Proton rocket, carrying the spacecraft failed and crushed in the Eastern Kazakhstan. The second and successful attempt took place on March 12, 2000, 0400 GMT. The Proton's Block DM upper stage performed two burns sending the 2,642-kilogram spacecraft toward its geostationary orbit 80 degrees East longitude over the equator. On May 12, 2000, the Express-6A reached its target position 80 degrees East of the Equator, replacing the Express-6 spacecraft. The success with the the launch of the second Express-A satellite put Russia on the way of preserving satellites' orbital positions, which the country registered in previous years, but which could expire unless an actual spacecraft had been placed there. The officials at Russia's Satellite Communications Company, RSCC, which since 1992 was entrusted with handling nation's comsats, came up with an intricate orbital chess match which would also allow older spacecraft with diminished capabilities to be replaced with newer, more powerful hardware. As of March 2000, RSCC officials planned that the older Express 6 (No. 12) spacecraft then hovering over 80 degrees east longitude would be moved farther east to the orbital position of 140 degrees east longitude. In turn, the Gorizont 33 (Statsionar 7) spacecraft, which then occupied the position of 140 degrees east longitude, had only five C-band transponders that are operational. Around the same time (March 2000), Alcatel delivered a communications payload with 12 transponders for another Express A spacecraft. The Express 3-A satellite was set for launch in June 2000 into orbital position 11 degrees West, where it would replace Gorizont 37 (Statsionar 11), which had only 7 working C-band transponders. The old Express-6 eventually moved into position of 103 degrees East, taking over duties of the obsolete Gorizont-36 satellite. Finally, Gorizont-33 moved further east to 140 degrees East, replacing Gorizont-33. Express-A3 (No. 3)
The mission was to lift off at 8:34 p.m. EST, 4:32 a.m. Moscow Time. However, the ground personnel encountered the problem around midnight Moscow Time on June 23, during the fueling of the vehicle, representative of Russian Aviation and Space Agency, Rosaviacosmos said. The launch was then rescheduled for 4:28 a.m. Moscow Time June 24 (8:28 p.m. EST June 23). 2000 June 24: The rocket carrying Express-3A communications satellite lifted off into the night sky over Baikonur Cosmodrome in Kazakhstan at 8:34 p.m. EST (4:32 a.m. Moscow Time on June 24). After a ten-minute powered flight, the Proton's third stage delivered the satellite and its Block DM upper stage into the initial parking orbit. In the next six-and-half hours, the upper stage fired its engines two times inserting the Express comsat into its final orbit 36,000 kilometers over the Equator. The satellite was positioned 11 degrees West latitude, where it took over the duties of the old Gorizont 26 spacecraft. The Express As are equipped with 17 communications transponders built by Alcatel Espace of France. The Russian Satellite Communications Company, RSCC, owns the Express-series spacecraft, while Moscow-based Intersputnik is their primary user. The launch of the Express 3-A came in the midst of the biggest backlog in Proton schedule in years. In addition to the June 6, 2000, launch, two Proton missions were competing for a launch window at the end of June 2000. Express-A1R 2002 June 10: The Proton rocket successfully launched Russian communications satellite. The four-stage booster blasted off at 05:14 Moscow Time from Baikonur Cosmodrome, carrying Express-A1R satellite, which belongs to Russia's State Company for Space Communications, GPKS. The spacecraft was built as a replacement for the first Express-A satellite lost in the Proton rocket failure in October 1999. The Express-A1R is equipped with 12 transponders, transmitting signals in C-band, 5 in Ku-band and one in L-band and it was expected to have a life span of seven years. The satellite, positioned in the equatorial orbit over the point 40 degrees Eastern longitude, will provide TV, radio and Internet services across the former Soviet Union. The spacecraft became the fourth and the last in the Express-A series developed by NPO PM enterprise based in Zheleznogorsk, Russia. The French company Alcatel Space Industries supplied communications payload for the spacecraft. Express-AM22 2003 Dec. 29: The Russian Proton rocket successfully delivered a spacecraft for the nation’s satellite communications company, RSCC. The Proton K vehicle with Block DM upper stage blasted off from Site 200 at Baikonur Cosmodrome at 04:00 local time on December 29, 2003 (2300 GMT on Dec. 28), carrying Express-AM22 spacecraft for Russian Satellite Communications Company, RSCC. The third stage of the Proton rocket inserted Block DM/Express-AM22 combination into an initial low Earth orbit, and the upper stage conducted two firings to raise the apogee and circularize the orbit at the altitude of 36,000 kilometers over the Equator. The Express-AM22, built by NPO PM development center in Zheleznogorsk, Russia in cooperation with Alcatel Space, has a projected life span of 12 years. The spacecraft carries 24 transponders and is expected to operate in the orbital position 53 degrees Eastern longitude over the Equator. The spacecraft was declared operational on March 9, 2004. Express-AM11 2004 April 27: In its third mission in six weeks, the Proton rocket successfully delivered a payload into geostationary orbit. The Proton K vehicle equipped with Block DM upper stage blasted off from Pad 39 at Site 200 of Baikonur Cosmodrome at 00:37 Moscow Time on April 27, 2004, carrying the Russian communications satellite Express-AM11. According to RKK Energia, the Block D manufacturer, the spacecraft and the upper stage separated at 07:10 Moscow Time on April 27. The satellite successfully reached the geostationary orbit. The spacecraft was declared operational on July 1, 2004. It was placed at the operation position 96.5 degrees East over the Equator. On March 29, 2006, Russian Satellite Communications Company, RSCC, the satellite operator, announced that at 03:41 Moscow Time Express AM-11 suddenly failed. According to the preliminary analysis by NPO PM, the satellite manufacturer, the failure took place as a result of a sudden external impact, which led to immediate release of fluid from the thermal control system. In its turn, venting liquid led to the loss of the attitude control by the spacecraft, rendering it useless. RSCC made effort to transfer the satellite's communications functions to other spacecraft, while by March 30, 2006, ground controllers managed to restore the attitude control onboard Express AM-11. However, they also found that the temperature onboard the satellite was approaching critical, threatening a complete loss of control over the vehicle. To avoid leaving the dead satellite in the operational orbit, at 14:00 Moscow Time, a sequence was initiated to direct the satellite into the "burial" orbit. On April 28, 2006, RSCC said that the satellite was parked in its final orbit 290 kilometers higher than geostationary orbit and all its systems were intentionally turned off. Express-AM1 2004 Oct. 30: The Russian Proton rocket successfully delivered a spacecraft for the nation’s satellite communications company, RSCC. The Proton K rocket with Block DM-01 upper stage blasted from Pad 39 at Site 200 at Baikonur Cosmodrome at 02:11 Moscow Time, on October 30, 2004, carrying the Express-AM1 satellite. After two firings of the upper stage, the payload successfully reached its final geostationary orbit at 08:45 Moscow Time on the same day. The satellite is to be positioned at 40 degrees East over the Equator. This was the third out five satellites in the series slated for launch before the end of 2005. The spacecraft was developed by NPO PM of Zheleznogorsk in cooperation with NEC NTS Space of Japan, Sodern of France and European consortium Astrium. Its payload, including nine C-band, 18 Ku-band and one L-band transponders, is designed to provide digital TV broadcasts, telephone communications and broad-band Internet access. The spacecraft has a projected life span of 12 years. The launch of the Express-AM1 was delayed from August 2004 and Oct. 28, 2004. At the time of the launch, the spacecraft was expected to enter service at the beginning of 2005. Express-AM2 2005 March 30: In its second mission since the beginning of the year, the Proton rocket successfully launched a Russian communications satellite. The Proton-K, equipped with Block DM upper stage, blasted off from Baikonur Cosmodrome on March 30, 2005 at 01:31 Moscow Time, carrying Express-AM2 spacecraft for Russian Satellite Communications Organization, RSCS. According to Russian officials, the satellite separated from the upper stage of the launch vehicle at 08:05 Moscow Time on the day of the launch. The spacecraft, built by NPO PM in Zheleznogorsk with the participation of Alcatel Space of France, is expected to operate in a geostationary orbit of 80 degrees West longitude over the Equator for the next 12 years. The launch of the Express-AM2 spacecraft had been earlier planned for December 2004, however it was reportedly delayed by the lack of funding for the manufacturing of the launch vehicle. Express-AM3 2005 June 24: The modernization of Russia's satellite communications network received a new bird in June 2005. A Proton-K (No. 410-07) equipped with Block D (11S861 No. 103L) upper stage and carrying the Express-AM3 comsat for the Russian Satellite Communications Organization, RSCS, blasted off from Baikonur Cosmodrome's Pad 39 at Site 200 on June 24, 2005 at 23:41 Moscow Time. The launch of the Express-AM3 spacecraft completed the modernization of the country's communications network. It was the fifth and last satellite of this type launch in the past two years. The spacecraft has a lifespan of 12 years. The mission was originally scheduled for June 23, 2005. The next generation of spacecraft was expected to reach launch pad in 2007. Express-AM33 2008 Jan. 28: Russia launched an Express-series communications satellite in the pre-dawn hours of Monday. The Proton-M rocket equipped with Briz-M upper stage lifted off on Jan. 28, 2008, at 3:18:00 Moscow Time from Site 200 in Baikonur Cosmodrome. It carried the Express-AM33 spacecraft toward the geostationary orbit, developed by NPO PM of Zheleznogorsk for Russia's Satellite Communications Company, RSCC. Russian space agency, Roskosmos, reported that the Briz-M upper stage and its payload successfully separated from the rocket and continued its path toward its final orbit. The 2,600-kilogram Express-AM33 satellite was to be placed at 96.5 degrees East longitude above the Equator, where it was expected to function for 12 years. The launch of Express-AM33 was previously expected in September 2007. APPENDIX Technical comparison of the Express and the proposed Express-M satellite:
A complete list of Express missions:
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Artist rendering of the Express spacecraft circa 1993. Credit: NPO PM
Coverage area of the Express system. Credit: NPO PM
Artist rendering of the Express M spacecraft circa 1993. Credit: NPO PM
Coverage area of the Express M system. Credit: NPO PM
Artist rendering of the Express A spacecraft circa 2000. Credit: RSCC
Scale model of the Express AM-1 spacecraft presented at the Le Bourget Air and Space Show in 2001. (Note enlarged solar arrays first proposed for Express M, as well as "squashed" rather then cylindrical body.) Copyright © 2001 Claude Mourier
The Express-A1R during pre-launch processing in 2002. Credit: NPO PM
The Express AM-22 during pre-launch processing in 2003. Credit: NPO PM
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