The Zenit-3SL carrier vehicle delivered the 5,511 kg (12,150 lbs) telecoms satellite, which will expand DISH network's capacity to its U.S. customers, into geosynchronous transfer orbit at 05:21 GMT.
"Congratulations to DISH Network, and to Space Systems/Loral for tonight's outstanding success," said Kjell Karlsen, president and general manager of Sea Launch. "We're proud of our role in DISH Network's continued success."
The Sea Launch consortium, established in 1995, is owned by Boeing, Norway's Kvaerner ASA, Ukraine's Yuzhnoye design bureau and Yuzhmash production association, as well as Russia's RSC-Energia. It is the only company that launches its vehicles from the Equator, which allows rockets to carry heavier payloads than from other latitudes.
Sea Launch has performed a total of 28 commercial launches for a range of companies, including EchoStar, DirecTV, XM Satellite Radio and PanAmSat.
The Zenit-3SLB is a modernized version of the Zenit-3SL, which was the rocket previously used at Sea Launch's floating platform on the Equator.