Hellas Sat 3 & GSAT-17

Hellas Sat 3-Inmarsat S EAN – a two-payload “condosat” produced by Thales Alenia Space for Hellas Sat and Inmarsat – was set to ride on a Falcon Heavy. However, it was switched to riding on an Ariane 5 after Inmarsat noted it was struggling against regulatory issues in Europe. Once in orbit, the Hellas Sat 3 component will deliver direct-to-home and telecom services to maintain and expand Hellas Sat’s business reach; while the Inmarsat S EAN component provides the satellite portion of Inmarsat’s new European Aviation Network. It will use a multi-beam mission in S-band and Ka-band for Inmarsat as well as a powerful Ku/Ka-Band mission of 44 Ku and 1 Ka transponders for Hellas-Sat.

GSAT-17 is an Indian communications satellite. Built by ISRO and operated by INSAT, it carries 24 C-band, 2 lower C-band, 12 upper C-band, 2 CxS (C-band up/S-band down), and 1 SxC (S-band up/C-band down) transponders. It additionally carries a dedicated transponder for data relay (DRT) and search-and-rescue (SAR) services. At the time of launch, GSAT-17 was the heaviest satellite built by ISRO.