Two telecommunications satellites were lofted to geostationary transfer orbit Aug. 29 from the Guiana Space Center in Kourou atop the fourth Ariane 5 heavy-lift rocket to be launched in 2013.

The spacecraft were Eutelsat 25B/Es’hail 1, built by Space Systems/Loral of Palo Alto, Calif., for a joint venture between Qatari-based operator Es’hailSat and Eutelsat of Paris; and New Delhi’s GSAT-7, built by the Indian Space Research Organization (ISRO).

The launch, which took place at 5:30 p.m. local time, was managed by European consortium Arianespace, which over the past 30 years has launched two-thirds of Eutelsat’s fleet. Eutelsat 25B/Es’hail 1 is the 27th Eutelsat spacecraft orbited by the Evry, France-based company, and the first launched for Qatar, which is developing a fleet of commercial communications satellites around its Doha-based anchor tenant, the Al Jazeera TV network.

The 6,000-kg (13,000-lb.) Eutelsat 25B/Es’hail 1 will operate at 25.5 deg. East, serving growing markets in the Middle East, North Africa and Central Asia, and ultimately taking over for Eutelsat 25C. In addition to ensuring Ku-band service continuity for Eutelsat and providing additional Ku-band capacity for Es’hailSat, the satellite will offer the two partners their initial Ka-band capacity.

GSAT-7 is the 17th ISRO satellite to launch on an Ariane rocket, starting with the launch of the Apple experimental satellite on flight L03 in 1981. Designed and built by ISRO in Bengaluru in southern India, the 2,650-kg multi-band GSAT-7 is expected to operate for more than seven years at 74 deg. East, where it will cover the entire Indian subcontinent.

Arianespace, which also operates a European variant of Russia’s Soyuz and Italy’s Vega light launcher, initially planned to launch six Ariane 5 vehicles and four Soyuz rockets from French Guiana in 2013. But the company is managing a crowded and complex launch manifest this year, and has so far struggled to find suitable pairings of large- and mid-sized spacecraft to co-manifest atop its Ariane 5 ECA, which launches roughly half of the world’s telecommunications satellites each year.

In addition, delays in the completion of Europe’s first two fully operational Galileo navigation satellites, which were slated to launch on an Arianespace Soyuz this fall, could reduce the number of planned Soyuz launches to just three in 2013. However, Arianespace is expected to announce an additional 2013 launch customer next month during the annual Euroconsult satellite conference here.