Another Proton rocket mission ends in success
BY STEPHEN CLARK
Posted: November 24, 2009
Updated @ 7:30 p.m. EST
Just eleven weeks after winning the contract from a troubled competitor, an International Launch Services Proton rocket gave a powerhouse European communications satellite a successful ride to orbit Tuesday.
Liftoff was delayed one day after Kazakh authorities withheld approval for the launch.
Ascending into a cloudy sky on six liquid-fueled engines, the Proton broke the sound barrier and soared into the upper atmosphere within two minutes. After reaching a suborbital trajectory, the Breeze M upper stage lit its engine for the first of five planned burns.
Seven minutes later, the upper stage shut down after reaching a stable parking orbit, according to launch officials. Four more Breeze M firings raised its altitude and reduce its orbital inclination.
The rocket released the 12,405-pound W7 payload at about 2330 GMT (6:30 p.m. EST). The Proton was targeting an orbit with a high point of 22,118 miles, a low point of 3,057 miles and an inclination of 20.9 degrees.
International Launch Services declared the mission a success, marking the 55th commercial Proton mission and the sixth this year.
Tuesday's launch came less than three months after ILS snatched the W7 launch contract from Sea Launch, another commercial rocket firm facing bankruptcy.
"Timely access to space is an essential component of Eutelsat's significant satellite expansion program of nine satellites to launch between 2008 and 2011, and most particularly in the case of W7," said Giuliano Berretta, the company's chairman and CEO, during the Sept. 7 contract announcement.
W7 was originally supposed to launch on the Proton rocket this summer, but the satellite moved to Sea Launch to take the place of the W2A spacecraft, which Eutelsat previously decided to switch from Sea Launch to ILS on the basis of schedule requirements.
After Sea Launch filed for Chapter 11 bankruptcy protection in June, it was clear the company would be unable to launch W7 this year, prompting the swap back to the Proton.
Seven satellites have moved from Sea Launch to ILS in the past year, including the XM 5 radio broadcasting satellite, which will launch on Proton in late 2010, according to Frank McKenna, president of Virginia-based ILS.
"If a satellite is not available on time to be launched, we have, on two occasions this year, been able to convert that into a launch opportunity for distressed customers," McKenna said.
In W7's case, ILS and Khrunichev, the Russian builder of the Proton, were able to put together a mission 11 weeks after the contract's announcement. But much of that work was already complete because W7 had been previously assigned to the Proton.
"It is a short integration schedule on the surface," McKenna said. "However, everything is being done just like we would normally do it. We were fortunate and flexible enough to be able to allow that to happen."
ILS has a backlog of 24 satellites after Tuesday's launch. The launch provider is taking orders for 2011 and 2012 after a busy manifest for next year that includes 7 or 8 commercial missions. One more commercial Proton flight this year is slated for late December with the DirecTV 12 satellite.
"The more general story that allows this to happen...is we have built up with Khrunichev to a steady rate of production and throughput and launch tempo that allows more flexibility in our manifest when there is a change that occurs," McKenna said.
Kjell Karlsen, Sea Launch's president and general manager, said Eutelsat kept the contract with Sea Launch for an unspecified satellite mission in late 2010 or 2011.
"Eutelsat had a need to get the W7 satellite up this year and we were just not in a position to be able to meet that date, so we worked with Eutelsat to come up with a mutually acceptable solution for both parties," Karlsen said.
The satellite is based on the Spacebus 4000 C4 platform from Thales Alenia Space. The craft can be configured to have up to 70 Ku-band transponders during its 15-year mission.
But first W7 will have to maneuver itself into a circular geosynchronous orbit 22,300 miles high. It will be positioned along the equator at 36 degrees east longitude, providing sweeping communications coverage of three continents.
It will be colocated with Eutelsat's W4 satellite at the 36 degrees East positon.
Digital broadcasting and direct-to-home video services will be beamed to customers in Russia and sub-Saharan Africa using W7. The new satellite will replace all the capacity on the SESAT 1 platform, which is being redeployed to another location after nearly 10 years of operations.
W7's communications payload is connected to five downlink beams for Europe, Russia, Africa, the Middle East, and Central Asia.
With the launch of W7, Eutelsat will be able to double the resources available for digital video and telecommunications services in Russia, Ukraine and sub-Saharan Africa.
A new high-powered fixed spot beam will offer new resources for South Africa and a steerable beam will be devoted to direct-to-home programming.
At least two Eutelsat payloads are due for launch next year as the operator continues its campaign to replace aging and obsolete satellites.
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