The two satellite passengers for Arianespace's next Ariane 5 mission are being fueled at the Spaceport, preparing them for a July 25 liftoff on the company's fifth flight in 2013 from French Guiana with its launcher family.

Utilizing the capacity and flexibility of the Spaceport's large S5 payload preparation facility, the Indian INSAT-3D meteorological platform is receiving its fuel load in the S5B hall, while Europe's Alphasat telecommunications spacecraft is undergoing a "top-off" in the separate S5A hall.

Alphasat is the largest European telecommunications satellite ever built, with a mass exceeding 6.6 metric tons when fueled. It also is the first to use the Alphabus spacecraft bus - the result of a coordinated European response to the increased market demand for larger telecommunication payloads.

Once in orbit, Alphasat will expand the U.K.-based Inmarsat operator's global mobile telecommunication network - delivering new capabilities in terms of performance and resource availability, providing 50 percent more accessible spectrum with double spectral efficiency and nearly 20 percent more channels. The satellite was built by Astrium, and its solar array will span nearly 40 meters once deployed in orbit, generating more than 12 kW of power.

The Alphasat mission was developed in the largest public-private partnership biggest of its kind, involving Inmarsat and the European Space Agency. This will provide the capacity to handle more than 750 channels in L-band, with improved quality - particularly for satellite phone users. When in service, Alphasat will augment Inmarsat's Broadband Global Area Network (BGAN) service, enabling communications across Europe, Asia, Africa and the Middle East with increased capacity.

Alphasat will ride in Ariane 5's upper payload position, while the INSAT-3D co-passenger is to be accommodated in the lower portion of the payload "stack." Developed by the Indian Space Research Organisation (ISRO) - the country's space agency, along with its Space Applications Centre - INSAT-3D is to provide enhanced meteorological observation and the monitoring of land/ocean surfaces with a six-channel imager and 19-channel sounder.

Also integrated on the Indian spacecraft is a data relay transponder, along with a payload to assist in satellite-aided search and rescue operations. INSAT-3D will have a mass at liftoff of approximately 2,100 kg.

Arianespace's July 25 mission is designated Flight VA214 to signify the 214th launch of an Ariane-series vehicle from French Guiana. It follows the company's launcher family missions already performed at the Spaceport in 2013 by two other heavy-lift Ariane 5s, along with one mission each of medium-lift Soyuz and lightweight Vega vehicles. Complementing the activity during the first half of 2013 was a Soyuz flight from Kazakhstan's Baikonur Cosmodrome, performed by the Starsem affiliate of Arianespace.