International Launch Services (ILS) have conducted another launch of the Russian Proton-M launch vehicle, this time carrying the Sirius FM-6 satellite on a multi-hour flight to its transfer orbit. Launch from the from the Baikonur Cosmodrome in Kazakhstan was on time at 18:08 GMT, the second flight of the Proton since its dramatic failure earlier in the year.
The Proton booster launching the Sirius FM-6 satellite 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). Overall height of the three stages of the Proton booster is 42.3 m (138.8 ft).
The Proton vehicle has a heritage of nearly 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 mission utilized a five-burn Breeze M mission design, with the first three stages of the Proton using a standard ascent profile to place the orbital unit (Breeze M upper stage and the Sirius FM-6 satellite) into a sub-orbital trajectory.
From this point in the mission, the Breeze M performed planned mission maneuvers to advance the orbital unit first to a circular parking orbit, then to an intermediate orbit, followed by a transfer orbit, and finally to a geostationary transfer orbit.
Separation of the Sirius FM-6 satellite occurred approximately 9 hours, 11 minutes, and 20 seconds after liftoff.
The Sirius FM-6 spacecraft is a high-power geostationary satellite for SiriusXM.
Sirius FM-6 will help with the delivery of commercial-free music, and premier sports, news, talk, entertainment and Latin programming, traffic and weather to more than 25 million subscribers – and it will also help in the delivery of traffic and other data service information to markets across North America for vehicles with navigational systems.
Built by SSL of Palo Alto, California, on their 1300 platform, the bird sports 20 Kw end-of-life power, SPT-100 plasma thrusters, one X-band uplink transponder and another S-band downlink transponder. From its orbital location at 116.15 degrees west longitude, it is anticipated to enjoy a service life of 15 years.
The launch marks the sixth SiriusXM satellite to be launched on an ILS Proton, the 27th SSL satellite to ride uphill on the Russian workhorse. The mission also marks the sixth ILS Proton launch in 2013, and the 83rd ILS Proton lift-off overall.
The mission was slightly delayed due to issues with the satellite ground station network required for the launch and early orbital operations of the spacecraft.
(Images via ILS).