ISRO to resume launches with GISAT-1A in September, ending seven-month hiatus as NavIC limps on three satellites

After a seven-month operational hiatus, ISRO is set to resume launches in the first week of September 2026 with GISAT-1A (EOS-05) aboard a GSLV Mk II rocket. GISAT-1A is a replacement for GISAT-1, lost in the August 2021 GSLV failure caused by a cryogenic upper-stage valve leak, and carries a 10-year mission life for disaster monitoring, agriculture and forestry imaging. NavIC satellite NVS-03, fuelled and ready at Sriharikota, is expected around October-November. The hiatus followed three failed missions in 2025-26: PSLV-C61 (May 2025) and PSLV-C62 (January 2026), both suffering third-stage anomalies, and GSLV-F15, which deployed NVS-02 but failed to complete orbit-raising manoeuvres.

ISRO enters this launch with a damaged reliability record — three of six missions in 2025-26 failed — and with its navigation constellation operationally impaired at precisely the moment dual-use PNT resilience matters most. GISAT-1A flies on the same GSLV Mk II architecture whose cryogenic stage failed in 2021. A successful September launch restarts ISRO's cadence and clears the path for NVS-03 to restore standalone NavIC positioning; a failure would compound both the cadence and credibility problems simultaneously.

NavIC's current three-satellite state forces India's armed forces to blend GPS, Galileo and GLONASS with degraded domestic positioning — precisely the dependency that sovereign PNT is meant to eliminate. The September launch is the hinge on which the entire FY2027 launch plan turns.

The launch outcome in the first week of September reshapes the FY2027 schedule. Whether the failure-analysis reports remain withheld affects both public accountability and industry confidence in ISRO's supply chain. The NVS-03 launch and the timeline for NavIC's return to four-satellite standalone operation are the immediate follow-on milestones.