MUMBAI: The launch of Inmarsat's second I-4 satellite took place on board a Sea Launch Zenit rocket from the Pacific Ocean yesterday.

The size of a London double-decker bus and weighing nearly six tons, once in operation, the Inmarsat-4 (I-4) spacecraft will deliver simultaneous voice and 3G-compatible broadband data services to mobile users across North, Central and South America. The satellite will now begin deployment and testing, with a number of key milestones ahead before being fully-deployed in geostationary orbit, 35,786 kilometres (22,237 miles) above the Equator, over northern Brazil.

The first Inmarsat-4 was launched in March 2005 and is already in commercial service above the Indian Ocean at 64ºE. Together, the two I-4 satellites will be able to deliver Inmarsat's new Broadband Global Area Network (Bgan) service to 85 per cent of the world's landmass.

Bgan is an IP and circuit-switched service that will offer voice telephony and a sophisticated range of high-bandwidth services, including internet access, videoconferencing, LAN and other data services, at speeds up to half a megabit per second.

Inmarsat CEO and chairman Andrew Sukawaty says, "The successful launch of the second I-4 satellite means that Inmarsat now has the world's most sophisticated commercial network for mobile voice and data services. It will support an unprecedented evolution of our services - more than doubling the bandwidth available to our mobile users. It marks the beginning of a new era for Inmarsat, in which we expect to roll out a new range of global mobile services to government, aid, and enterprise users."

Inmarsat's I-4 satellites are built by EADS Astrium and are part of an eight-year, $1.5 billion development of Inmarsat's next-generation satellite network. They are 60 times more powerful and have 20 times more capacity than their predecessors, the Inmarsat-3 satellites.