ISRO Launches GSLV-F18 to Boost NavIC Satellite Network

UPDATE - follow-up to ISRO set to launch GSLV-F18 carrying navigation satellite NVS-03 | LIVE: ISRO has launched its third space mission of 2026 using the GSLV-F18 rocket to carry the 2,250-kg NVS-03 satellite into orbit.

Mission Details

Around 18 minutes and 40 seconds after lifting off from the Second Launch Pad at Sriharikota, the GSLV-F18 rocket is set to deploy the satellite into an initial Geosynchronous Transfer Orbit. ISRO will use onboard thrusters to raise it to its final orbit. NVS-03 carries both an indigenous atomic clock and procured atomic clocks, along with L1, L5, and S-band signals to improve regional navigation services. The launch follows previous gaps, including a 19-month gap between NVS-01 in May 2023 and NVS-02 in January 2025, and a nearly 20-month gap before NVS-03.

Network Status

Out of 11 total satellites in the NavIC constellation, only three remain capable of primary functions. These are first-generation satellites IRNSS-1B and IRNSS-1I, and second-generation satellite NVS-01. IRNSS-1B has crossed its 10-year lifespan, IRNSS-1I functions until about 2028, and NVS-01 has roughly a decade left. Meanwhile, NVS-02 suffered engine failure preventing orbit raising. Restoring core services requires at least four operational satellites, meaning ISRO needs to launch NVS-04 and NVS-05 next, while a stable system requires six to seven satellites.

Context

NavIC is India's home-grown regional satellite navigation system designed to provide independent positioning services similar to systems operated by the United States, Russia, and China. Maintaining a reliable orbital network requires regular launches and backup satellites to offset aging spacecraft and occasional mission setbacks.