PARIS — Europe’s Ariane 5 ECA rocket on May 20 successfully placed telecommunications satellites for India and a Singapore/Taiwan joint venture into geostationary transfer orbit in the third of a planned six launches this year. Both satellites’ owners reported their spacecraft were healthy in orbit.

It was the 44th consecutive launch success for Ariane 5.

The ST-2 satellite will replace the ST-1 spacecraft launched in 1998 at 88 degrees east for a joint venture of Singapore Telecommunications Ltd. (SingTel) and Chunghwa Telecom of Taiwan. The satellite will offer substantially more capacity than ST-1, although the exact number of C- and Ku-band transponders was not announced.

ST-2 was built by Mitsubishi Electric of Japan (Melco) and was the first commercial telecommunications satellite order won by Melco for a non-Japanese customer. ST-2 weighed 5,090 kilograms at launch and is based on Melco’s DS2000 satellite frame, which is also used on Japan’s MTSat-2 satellite and SkyPerfect JSat’s Superbird C2 spacecraft. ST-2 is designed to provide 11.8 kilowatts of power to its payload at the end of its planned 15-year service life.

Also riding on the Ariane 5 was the Gsat-8 built and owned by the Indian Space Research Organisation, India’s space agency, which also controls that nation’s satellite telecommunications market. Gsat-8 is an I-3K platform equipped with 24 Ku-band transponders. It will be operated at 55 degrees east and is designed to operate for 12 years.

Gsat-8 also carries a small communications payload to be used as part of India’s Gagan regional system to verify and improve positioning, navigation and timing services provided by the U.S. GPS constellation of medium Earth orbiting satellites. Similar regional systems operate in North America and Europe, and are being developed by Japan, China and Russia.