GSAT-18
| Mission type | Communications |
|---|---|
| Operator | INSAT |
| COSPAR ID | 2016-060A |
| SATCAT no. | 41793 |
| Website | GSAT-18 |
| Mission duration | Planned: 15 years Elapsed: 8 years, 8 months, 14 days |
| Spacecraft properties | |
| Bus | I-3K |
| Manufacturer | ISRO Satellite Centre Space Applications Centre |
| Launch mass | 3,404 kg (7,505 lb) |
| Dry mass | 1,480 kg (3,263 lb) |
| Power | 6,474 watts |
| Start of mission | |
| Launch date | 5 October 2016, ≈20:30 UTC |
| Rocket | Ariane 5 ECA, VA-231 |
| Launch site | Guiana Space Centre ELA-3 |
| Contractor | Arianespace |
| Orbital parameters | |
| Reference system | Geocentric |
| Regime | Geostationary |
| Longitude | 74° E |
| Perigee altitude | 35,750 km (22,214 mi) |
| Apogee altitude | 35,822 km (22,259 mi) |
| Inclination | 0.0616° |
| Epoch | 11 June 2017 01:46:00 UTC |
| Transponders | |
| Band | 24 × C band 12 × extended C band 12 × Ku band 2 × Ku beacon |
GSAT-18 is an Indian communications satellite. Built by ISRO and operated by INSAT, it carries 24 C-band, 12 extended C-band, and 12 Ku-band transponders.As of 2025, 6 transponders in the spacecraft are kept in idle, as GSAT-14 covers their spectrum.they are expected to be online in early 2027.
The satellite was launched on 5 October 2016 at approximately 20:30 UTC aboard an Ariane 5 ECA rocket from the Guiana Space Centre in Kourou, French Guiana. The launch vehicle inserted the satellite into a geosynchronous transfer orbit, and once in service it will occupy the orbital slot at 74° East longitude. The total cost of the satellite and launch services was about US$153 million.
GSAT-18 was originally scheduled to launch on 12 July 2016 alongside Japan's Superbird-8 satellite, but a shipping mishap which damaged Superbird-8 forced a delay in the launch schedule. Arianespace later paired GSAT-18 with Australia's Sky Muster II for a 4 October 2016 launch. The launch was delayed 24 hours to 5 October due to excessively high crosswinds at the launch site.