Ekspress-AM4R

{{Short description|Russian communications satellite}}

{{Use British English|date=March 2021}}

{{Use dmy dates|date=March 2021}}

{{Infobox spaceflight

| name = Ekspress-AM4R

| names_list = Экспресс-АМ4Р
Express-AM4R

| image =

| image_caption =

| image_size = 300px

| mission_type = Communications

| operator = Russian Satellite Communications Company (RSCC)

| COSPAR_ID =

| SATCAT =

| website = https://eng.rscc.ru/

| mission_duration = 15 years (planned)
Failed to orbit

| spacecraft = Ekspress-AM4R

| spacecraft_type = Eurostar

| spacecraft_bus = Eurostar-3000

| manufacturer = EADS Astrium

| launch_mass = {{cvt|5775|kg}}

| dry_mass = {{cvt|1465|kg}}

| dimensions =

| power =

| launch_date = 15 May 2014, 21:42:00 UTC

| launch_rocket = Proton-M / Briz-M

| launch_site = Baikonur, Site 200/39

| launch_contractor = Khrunichev State Research and Production Space Center

| entered_service = Failed to orbit

| disposal_type =

| deactivated =

| last_contact =

| orbit_reference = Geocentric orbit (planned)

| orbit_regime = Geosynchronous orbit

| orbit_longitude = 80° East

| apsis = gee

| trans_band = 63 transponders:
30 C-band
28 Ku-band
2 Ka-band
3 L-band

| trans_frequency =

| trans_bandwidth =

| trans_capacity =

| trans_coverage = Russia

| insignia =

| insignia_caption =

| insignia_size = 200px

| programme = Ekspress constellation

| previous_mission = Ekspress-AT2

| next_mission = Ekspress-AM6

}}

Ekspress-AM4R ({{langx|ru|Экспресс-АМ4Р}} meaning Express-AM4R) {{cite web|url=http://ria.ru/space/20140228/997566018.html|title=Ракета "Протон-М" для запуска "Экспресс-АМ4Р" доставлена на Байконур|agency=RIA Novosti|date=28 February 2014|access-date=25 March 2021}} was a Russian communications satellite intended for operation by the Russian Satellite Communications Company (RSCC). Constructed as a replacement for Ekspress-AM4, which was left unusable after the upper stage of the launch vehicle carrying it malfunctioned, Ekspress-AM4R was also lost due to a launch failure.{{cite web|url=http://www.russianspaceweb.com/ekspress_am4r.html|title=Proton fails again with Ekspress satellite|first=Anatoly|last=Zak|publisher=RussianSpaceWeb.com|access-date=25 March 2021|url-status=dead|archive-url=https://web.archive.org/web/20140527214354/http://www.russianspaceweb.com/ekspress_am4r.html|archive-date=27 May 2014}}

Satellite description

Astrium, which had become part of Airbus Defence and Space by the time of the satellite's launch, constructed Ekspress-AM4R, which was based on the Eurostar-3000 satellite bus.{{cite web|url=http://www.astrium.eads.net/en/programme/express-am4r-and-express-am7.html|title=Express-AM4R and Express-AM7|publisher=Astrium|access-date=25 March 2021|archive-url=https://web.archive.org/web/20130403003242/http://www.astrium.eads.net/en/programme/express-am4r-and-express-am7.html|archive-date=3 April 2013|url-status=dead}} It was identical in design to Ekspress-AM4, with a mass of {{cvt|5775|kg}} and a planned operational lifespan of fifteen years. The satellite carried sixty-three transponders: thirty operating in the C-band of the electromagnetic spectrum, twenty eight in the Ku-band, two in the Ka-band and three in the L-band. It was to have been the largest and most powerful satellite in the Ekspress constellation.{{cite web|last=Krebs|first=Gunter|title=Ekspress-AM4, -AM4R|url=http://space.skyrocket.de/doc_sdat/ekspress-am-4.htm|publisher=Gunter's Space Page|date=11 December 2017|access-date=25 March 2021}}

Launch

Khrunichev State Research and Production Space Center was contracted to launch Ekspress-AM4R, using a Proton-M / Briz-M launch vehicle - the same configuration that had failed to deploy Ekspress-AM4. The launch took place from Site 200/39 at the Baikonur Cosmodrome, at 21:42:00 UTC on 15 May 2014. Shortly after launch the launch vehicle was reported to have encountered a problem during third stage flight, and as a result the satellite failed to reach orbit.{{cite web |url=http://www.nasaspaceflight.com/2014/05/russian-proton-m-launches-with-ekspress-am4r/|title=Russian Proton-M suffers failure during Ekspress-AM4R launch|first1=William|last1=Graham|first2=Chris|last2=Bergin |publisher=NASASpaceFlight.com|date=15 May 2014|access-date=25 March 2021}}

References