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Ekspress-AM7 communications satellite The Ekspress-AM7 satellite was developed by the European consortium Airbus Defense and Space (formerly EADS Astrium) for the Russian Satellite Communications Company, GPKS. The spacecraft was designed to provide all major forms of civilian communications from the geostationary orbit 36,000 kilometers above the Equator, following its launch on the Proton-M/Briz-M rocket on March 19, 2015.
Ground track of the Proton-M/Briz-M mission to deliver Ekspress-AM7 satellite on March 19, 2015.
Launch profile The liftoff of the Proton-M rocket with Ekspress-AM7 satellite took place as scheduled on March 19, 2015, at 01:05:00 Moscow Time (22:05 GMT, 6:05 p.m. EDT on March 18) from Pad No. 39 at Site 200 in Baikonur. Following five maneuvers of the Briz-M stage, the Ekspress-A7 satellite was released into its planned orbit nine hours 13 minutes after the launch. According to GKNPTs Khrunichev, the first, the second and the third stages of the Proton-M rocket were programmed to propel the payload section, including Briz-M stage and the satellite along a standard eastward ascent trajectory from Baikonur matching an orbital inclination of 51.5 degrees toward the Equator. The payload section should separate from the third stage on a suborbital trajectory, after which, Briz-M was to fire its engine for the first time to reach an initial parking orbit. The second Briz-M maneuver should push the stack to an intermediate orbit, followed by the third and fourth firings to reach a transfer orbit. As usual, the empty external tank of the Briz-M was scheduled to separate between third and fourth maneuvers. Once the payload section reaches an apogee of the transfer orbit, the Briz-M was programmed to conduct the fifth and final engine firing to enter the geostationary transfer orbit. The stage should then orient the spacecraft in correct attitude and spin it before separation nine hours 13 minutes after the liftoff from Baikonur. Following the satellite release and an orbit-measurement session, Briz-M will make two additional maneuvers to increase its distance from the satellite and to enable safe opening of its onboard valves to empty pressurized compartments. The procedure is designed to prevent possible explosion and resulting proliferation of space junk. Ekspress-AM7 satellite
The prime manufacturer of the Ekspress-AM7 satellite, the European consortium Airbus Defense and Space based the spacecraft on its Eurostar-E3000 standard platform. Two of the satellite's predecessors, Ekspress-AM4 and Ekspress-AM4R, also based on the E3000 platform, were lost in botched Proton launches in 2011 and in 2014. Ekspress-AM7 is expected to replace Ekspress-AM1 in the orbital position of 40 degrees East longitude over the Equator. According to Airbus, Ekspress-AM7 was to have a communications payload of 62 active transponders (24 in C-band, 36 in Ku-band, two in L-band). The company said that the spacecraft would provide high-performance coverage over the Russian Federation, as well as across former Soviet republics and adjacent areas with the help of steerable antennas onboard the satellite, reaching as far as the Middle East, Central Asia, India and Africa. Known specifications of the Ekspress-AM7 satellite:
Mission history The Russian Satellite Communications Company, GPKS, ordered the AM7 satellite for its Ekspress family of Russian communications satellites from the European consortium EADS Astrium (later renamed Airbus Defense and Space) in March 2012. Simultaenously, a contract was signed to build the ill-fated Ekspress-AM4R. The launch of the Ekspress-AM7 satellite was originally planned at the beginning of 2014, but it was later postponed to the fall of that year. By August 2013, the launch was set for early March 2015. In the wake of the Russian annexation of Crimea, the conflict in Ukraine and resulting European sanctions in 2014, there were reports in the Russian press, that the all-but-ready Ekspress-AM7 could be impounded in Europe. However an Airbus representative in Moscow explained ComNews.ru web site that the delays with the delivery of the satellite were caused by the May 2014 accident with the Proton rocket and resulting shift of the vehicle's launch manifest from 2014 to 2015. By the end of 2014, the launch of Ekspress-AM7 was re-scheduled for early March 2015, however at the beginning of the year it was pushed back slightly to March 17 and then to March 19. The satellite arrived at Baikonur on February 19, 2015, traditionally one month before its expected launch. After a smooth launch processing, the rocket with the spacecraft left the assembly building for the fueling station on March 13, followed by a transfer to the launch pad No. 39 at Site 200 two days later.
Proton-M with Ekspress-AM7 shortly after its rollout to the launch pad on March 15, 2015.
Read much more about the history of the Russian space program in a richly illustrated, large-format glossy edition:
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