Arianespace and the Indian Space Research Organisation (ISRO) are testing and tweeking their respective vehicles in anticipation of the June 28 launch from the Spaceport in French Guiana. Arianespace’s responsibility involves their heavy-lift Ariane 5 which will carry a dual payload: ISRO's GSAT-17 communications satellite and the Hellas Sat 3 – Inmarsat S EAN multi-mission relay satellite for Inmarsat and Hellas-Sat.
The tests that the ISRO's GSAT-17 has been undergoing include ground-based checkout activity, such as the deployment of its solar panels and antenna reflectors in the Spaceport’s S5 payload preparation facility’s S5C large clean room hall.
This deployment testing is a routine procedure with Indian satellites prior to launch. For the solar panels’ extension, an overhead latticework helped support the solar panels as they opened to their full length, simulating the zero gravity conditions in space. Upon validating the proper operation, Indian technicians stowed the panels against the satellite in their final liftoff configuration. Afterwards, the satellite’s two antenna reflectors were similarly deployed and restowed during activity in the clean room.
Launching aboard the upcoming Ariane 5 mission, designated Flight VA238 in Arianespace’s launcher family numbering system, GSAT-17 will be deployed second in the flight sequence, following Ariane 5’s release of Hellas Sat 3, Inmarsat S EAN. The payload designed for Inmarsat will deliver an S-band service across all 28 member states of the European Union, plus Norway and Switzerland, while the FSS/BSS Hellas Sat payload will cover Europe, Middle East and Southern Africa.
GSAT-17 is based on the I-3K extended spacecraft bus, with a liftoff mass set at 3,425 kg. The satellite’s relay payload is composed of Ku-band, Normal C-band and Extended C-band transponders. The satellite also carries CxS and SxC transponders as well as DRT and SAR transponders.
Arianespace is targeting a total of 12 missions in 2017 utilizing its family of the heavy-lift Ariane 5, medium-lift Soyuz and light-lift Vega. So far this year, the launch services company has performed six flights from the Spaceport, composed of three with Ariane 5, two utilizing Soyuz and one with Vega.