Russia launched another of their Proton-M rockets on Thursday, with the mission tasked with lofting the Ekspress-AM4R telecommunications satellite into orbit. Launch of the Proton-M rocket took place from Launch Pad 39 at the Baikonur Cosmodrome in Kazakhstan at 21:42 GMT. However, an unspecified failure was noted during third stage flight. The rocket and satellite are lost.
The Proton vehicle is a veteran of the Russian space program, with hundreds of launches since 1965.
It is built by Khrunichev Research and State Production Center, with majority owner International Launch Services (ILS) also flying the vehicle on commercial missions.
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 Russians are currently using the Phase III Proton-M launch vehicle, which was flight proven on the Russian Federal dual mission of Express AM-44 and Express MD-1 in February 2009 and performed its first commercial launch in March 2010 with the Echostar XIV satellite.
The phase III configuration is the current standard configuration for ILS Proton, providing 6150 kg of GTO performance, which is an increase of 1150 kg over the original Proton Breeze M, while maintaining the fundamental design configuration.
As a workhorse, the Proton-M has suffered from its fair share of failures, none more dramatic than the July failure, when the rocket rolled from one side to the other, prior to crashing into the cosmodrome.
The Russian government launch was carrying three satellites for the GLONASS navigation system.
The vehicle then enjoyed several successful launches under its belt since the failure. However, Thursday’s mission appears to have added to the list of Proton’s failures.
It is not yet know what went wrong, with only the Russian commentator noting an anomoly and cutting the webcast. The vehicle was on to the third stage segment of flight at this point.
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The mission was set to send the spacecraft to its transfer orbit via the Upper Stage called the Briz-M, which carries out multiple burns to deploy the satellites into their respective orbits.
The core of the Briz-M which contains the engines, propellant tanks, avionics and electronic equipment, is based on the Briz-K.
Mounted around the outside of the core is the Auxiliary Propellant Tank, which contains up to 14.6 tonnes of propellant. Fuel is drained from the APT first, and once empty it is jettisoned to reduce the vehicle’s mass.
A single 14D30 engine powers the Briz-M, with four 11D458 vernier engines and twelve 17D58E thrusters being used to provide attitude control. It can make up to eight burns, and produces 19.6 kilonewtons of thrust.
The Astrium-built Ekspress-AM4R – which now appears to be lost – had a mass at launch of 5,741 kg. It is based on the Eurostar E3000 platform and was expected to enjoy a service life of 15 years.
The spacecraft sported 30 C-band, 28 Ku-band, 2 Ka-band and 3 L-band transponders and was to provide digital television and radio broadcasting services across Russia, mobile presidential and government communications, multimedia services (telephony, video conferencing, data transmission, Internet access) as well as solutions based on VSAT network technologies.
Ekspress-AM4R was launched from Pad 39 of Area 200 at the Baikonur Cosmodrome. The launch was set to take place last month. However, engineers were delayed in repairing Pad 200/39’s ground electrical umbilical unit 8U259, which caused last year’s failed Proton rocket to lift off half-a-second early from Pad 81/24.
One of four Proton launch complexes at Baikonur, Pad 39 has been used for the majority of Proton-M/Briz-M launches, and is overall the most used of the four pads.
The first launch from Pad 39 occurred in February 1980, and since then over 100 launches have been made from it, including the core and three other modules of Mir, three probes to Venus, a probe to Phobos, and the failed Mars-96 mission.