ILS Proton-M successfully launches Inmarsat-5 F1

by Chris Bergin

International Launch Services (ILS) have successfully launched another Russian Proton-M launch vehicle, tasked with lofting the Inmarsat-5 F1 satellite on a flight to its transfer orbit that took over 15 hours to complete. Launch from the from the Baikonur Cosmodrome in Kazakhstan was on time at 12:12 GMT on Sunday.


The Proton booster that launched the Inmarsat-5 F1 satellite was 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 was 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.

Z4The 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 involved a five-burn Breeze M mission design, utilizing the Supersynchronous Transfer Orbit mission design.

The first three stages of the Proton used the standard ascent profile to place the orbital unit (Breeze M upper stage and the Inmarsat-5 F1 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 supersynchronous transfer orbit.

Separation of the Inmarsat-5 F1 satellite occurred approximately 15 hours, 31 minutes after liftoff.

The target orbit at separation is aiming for a perigee of 4,341km and an apogee: 65,000 km with an inclination of 26.75 degrees.

“We are honored to share this momentous occasion with Inmarsat, true innovators in the satellite communications industry, with the first ILS Proton launch of three in the Global Xpress constellation,” noted ILS President Phil Slack.

“Today’s ILS Proton launch builds on a strong relationship between Inmarsat and ILS dating back to 2008 with the launch of an Inmarsat-4 satellite. We thank the teams who worked tirelessly on the successful launch of I-5 F1 and look forward to our upcoming missions with Inmarsat.”

Z7This Inmarsat satellite is one of three Ka-band Inmarsat-5 satellites that were ordered from Boeing by the London based company, at a cost of about $1 billion under a fixed-price contract, with options.

The three 6,100kg BSS-702HP platform commercial spacecraft that will operate in geosynchronous orbit with flexible global coverage.

Each Inmarsat-5 satellite will carry 89 Ka-band beams that will operate in geosynchronous orbit with flexible global coverage. The satellites are designed to generate approximately 15 kilowatts of power at the start of service and approximately 13.8 kilowatts at the end of their 15-year design life.

“We remain focused on continuing to complete crucial milestones to successfully deliver this series of satellites,” noted Craig Cooning, vice president and general manager of Boeing Space & Intelligence Systems. “The Inmarsat-5 series is built on our 702HP model of satellites, which is flight-proven with over 20 spacecraft in orbit.”

Z46The spacecraft has two solar wings with five panels, each of ultra triple-junction gallium arsenide solar cells. The BSS-702HP carries the xenon ion propulsion system (XIPS) for all on-orbit attitude control.

When operational, the Inmarsat-5 satellites will provide Inmarsat with a comprehensive range of global mobile satellite services, including mobile broadband communications for deep-sea vessels, in-flight connectivity for airline passengers and streaming high-resolution video, voice and data.

“Global Xpress is the result of three years of planning and, together with a fourth Inmarsat-5 satellite we ordered recently from Boeing, represents an investment of US$1.6 billion in our next generation of high bandwidth, high capacity, mobile broadband communications satellites,” added Rupert Pearce, CEO, Inmarsat.

“I wish to thank the teams at Inmarsat and Boeing for their hard work and ingenuity in bringing this highly innovative programme to fruition. We also thank our experienced partners at ILS and Khrunichev for their dedication and assurance in ensuring this mission was successful. We look forward to our future ILS Proton launches next year.”

The Boeing satellites will provide Inmarsat with the ability to adapt to shifting subscriber usage patterns of high data rates, specialized applications and evolving demographics.

Also, in a separate arrangement, Boeing also entered into a distribution partnership with Inmarsat to provide L- and Ka-band capacity to key users within the U.S. government.

The launch marks the seventh ILS Proton launch in 2013, the 84th ILS Proton launch overall, the third Inmarsat satellite to be launched on Proton and the 16th Boeing satellite launched on an ILS Proton.

(Images via ILS and Boeing).

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