A Russian Government Proton-M was action on Thursday, lofting the Ekspress AMU1 communications satellite on what was a multi-hour flight to a geostationary orbit via its Briz-M Upper Stage. The Russian workhorse launched from its traditional home at the Baikonur Cosmodrome in Kazakhstan at 21:31 UTC.
The Proton booster tasked with carrying the satellite into space is 4.1 m (13.5 ft) in diameter along its second and third stages, with a first stage diameter of 7.4 m (24.3 ft).
The overall height of the three stages of the Proton booster is 42.3 m (138.8 ft).
While it has suffered its share of failures, the Proton vehicle has a long heritage of over 400 launches since 1965 and is built by Khrunichev Research and State Production Center, one of the pillars of the global space industry and the majority owner of ILS.
The first stage consists of a central tank containing the oxidizer surrounded by six outboard fuel tanks. Each fuel tank also carries one of the six RD-276 engines that provide first stage power.
Total first stage vacuum-rated level thrust is 11.0 MN (2,500,000 lbf).
Of a conventional cylindrical design, the second stage is powered by three RD-0210 engines plus one RD-0211 engine and develops a vacuum thrust of 2.4 MN (540,000 lbf).
Powered by one RD-0213 engine, the third stage develops thrust of 583 kN (131,000 lbf), and a four-nozzle vernier engine that produces thrust of 31 kN (7,000 lbf).
Guidance, navigation, and control of the Proton M during operation of the first three stages is carried out by a triple redundant closed-loop digital avionics system mounted in the Proton’s third stage.
The Briz-M (Breeze-M) upper stage is the Phase III variant, a recent upgrade which utilizes two new high-pressure tanks (80 liters) to replace six smaller tanks, along with the relocation of command instruments towards the centre – in order to mitigate shock loads when the additional propellant tank is being jettisoned.
The launch date had suffered from delays, including a scrub at around T-30 minutes on Wednesday due to high upper level winds.
Airbus Defence and Space built the satellite under contract from the Russian Satellite Communications Company (RSCC).
Express AMU1 – or EUTELSAT 36C as it is also known – will provide follow-on and expansion capacity for the EUTELSAT 36A broadcast satellite operating at 36° East.
The Eurostar E3000 spacecraft is a state-of-the-art high-capacity satellite with up to 70 transponders. It will provide coverage for broadcast services in the European part of the Russian Federation in Ku and Ka bands, and ensure service continuity and growth for broadcast markets developed by Eutelsat in sub-Saharan Africa.
Express AMU1 is the 70th satellite of the Eurostar series.
The multibeam Ka-band antennas feature a highly innovative array fed reflector antenna technology developed by Airbus Defence and Space.
Based on Airbus Defence and Space’s highly reliable Eurostar E3000 platform, Express AMU1/EUTELSAT 36C has a launch mass of 5,700 kg and a spacecraft power in excess of 15 kW. Its design lifetime is 15 years in orbit.
(Images via Roscosmos and Airbus Defence and Space).