A Proton booster successfully guided an Asian communications satellite into orbit Tuesday, six months after a last-minute rocket switch to meet the customer's schedule demands.

The Proton blasts off with AsiaSat 5. Credit: ILS

AsiaSat 5, a four-ton broadcasting and networking satellite, will spend the next 15 years circling Earth and beaming television programming, voice communications and multimedia services to the world's most populated continent.

The 8,289-pound spacecraft will be operated by Hong Kong-based Asia Satellite Telecommunications Co. Ltd.

AsiaSat moved the payload to the Proton rocket in February after another launch provider, Sea Launch, experienced delays and could not meet the company's schedule requirements.

"In late February, my boss walked into my office and said 'I got a challenge for you,'" said John Palme, AsiaSat 5's program director at International Launch Services, the U.S.-based firm overseeing commercial Proton launches.

The new satellite will replace the AsiaSat 2 platform launched in 1995. The aging spacecraft could run out of fuel by 2011, officials said.

"It gives our customers a lot more confidence to know that we're replacing AsiaSat 2 well before its scheduled retirement date, predominately because (ILS was) able to step in and offer us a very quick turnaround and launch from the day we signed the contract up to now," said Peter Jackson, CEO of AsiaSat.

ILS offered a launch by the middle of August, less than six months after the contract was inked.

"This is the real value that ILS Proton offers our customers and we are proud to have met AsiaSat's demanding business imperative for the replacement strategy of AsiaSat 2," said Frank McKenna, president of ILS.

AsiaSat 5 was bolted atop the Russian launcher for liftoff at 1947 GMT (3:47 p.m. EDT) Tuesday from the Baikonur Cosmodrome in Kazakhstan.

With six engines blazing a fiery trail through the night sky, the 185-foot-tall rocket broke the sound barrier and soared into the upper atmosphere within two minutes, before igniting its second stage main engine and shedding its spent lower stage.

The Proton's second and third stages performed well, depositing the Breeze M upper stage and AsiaSat 5 in a ballistic trajectory just short of orbital velocity.

The Breeze M, fueled by toxic hydrazine propellant, ignited four times to accelerate AsiaSat 5 to higher altitudes and reduce the orbit's inclination.

The upper stage deployed AsiaSat 5 at about 0502 GMT (1:02 a.m. EDT) Wednesday, completing the marathon launch sequence.

ILS declared the launch a success in a statement issued early Wednesday.

Plans called for the payload to be released in an orbit with a high point of 22,236 miles, a low point of 11,154 miles and an inclination of 6 degrees, according to ILS.

AsiaSat 5's own engines will be used to nudge the satellite higher over the next few weeks, eventually settling in a circular geosynchronous orbit 22,300 miles above the equator.

Built by Space Systems/Loral in Palo Alto, Calif., AsiaSat 5's operational station will be at 100.5 degrees east longitude. The satellite's orbital speed will match the rate of Earth's rotation, allowing the craft to hover directly above the island of Sumatra.

AsiaSat 5. Credit: Space Systems/Loral

The spacecraft carries 26 C-band transponders able to reach more than 53 countries spanning from Russia to New Zealand and from Japan to parts of Africa, according to AsiaSat.

AsiaSat 5's 14 Ku-band transponders will be attached to beams covering East Asia and South Asia. A third Ku-band beam can be switched to satisfy market demands.

"The launch of AsiaSat 5 is significant to the company and to its users because it will provide a continuity to the users on AsiaSat 2," said Sabrina Cubbon, AsiaSat's general manager of marketing. "AsiaSat 2 is the region's leading satellite for international broadcasting for news distribution."

The Chinese government is a leading user of AsiaSat 2 capacity for communications services, including weather information and news broadcasts. Those services will now be moved to AsiaSat 5, according to company officials.

The next Proton mission is scheduled for the middle of September, when another ILS-managed flight will launch the Canadian Nimiq 5 communications satellite.

A Russian government launch will follow around Sept. 25 with a trio of Glonass navigation spacecraft.