GSAT-7/INSAT-4F

Image: Indian Space Research Organization
Image: Indian Space Research Organization

The GSAT-7 Satellite, also known as INSAT-4F, is a multi-Band communications satellite that will be used to provide communication services to the Indian navy. GSAT-7 was manufactured by the Indian Space Research Organization for operation by Insat.

The 2,550-Kilogram satellite is based on ISRO’s I-2000 Satellite bus – a modular design for satellites in the 2,000-Kilogram weight-class. Two solar panels with two panels provide about 2,500 Watts of electrical power. The communications payload consumes about 2,000 Watts of power. GAST-7 is equipped with a multi-band payload including UHF, S-Band, C-Band and Ku-Band transponders to provide connectivity to a variety of communications services.

The satellite is equipped with a Liquid Apogee Motor. It provides a thrust of 440 Newtons and uses Mixed Oxides of Nitrogen as fuel and Unsymmetrical Dimethylhydrazine as oxidizer.

The engine operates and an mixture ratio (O/F) of 1.65 and has a nozzle ratio of 160. The engine’s injector is a co-axial swirl element made of titanium while the thrust chamber is constructed of Columbium alloy that is radiatively cooled. The engine is certified for long firings of up to 3,000 seconds. The Propellants are stored in spherical tanks that are pressurized with Helium.

GSAT-7 will operate for at least 9 years from 74 degrees East in Geostationary Orbit, covering India and surrounding regions.