The Indian Space Research Organisation (ISRO) on Thursday, November 12, successfully completed a ground static test of a revised third-stage (PS3) solid motor of the Polar Satellite Launch Vehicle (PSLV) at the Static Test Facility of the Satish Dhawan Space Centre in Sriharikota, the agency said in its announcement.

Source: ISRO (via World of Now)

The test is an important step towards restoring the reliability of the PSLV, India's workhorse launcher, after two consecutive missions were hit by third-stage anomalies, the Times of India reported from Bengaluru.

Source: Times of India (via AllTotalNews)

The first setback came on May 18, 2025, when PSLV-C61, carrying the EOS-09 Earth-observation satellite, could not complete its mission after an observation in the third stage. A second anomaly followed on January 12, 2026, during PSLV-C62, which was carrying the EOS-N1 satellite and 15 additional payloads; the vehicle deviated from its flight path near the end of the PS3 stage, ISRO said.

What ISRO changed in the PS3

ISRO said the PS3 configuration was revisited comprehensively — covering design margins, raw-material acceptance criteria, assembly procedures and quality checks. Essential improvements were made to the nozzle configuration to improve design margins, the adequacy of design margins for the mechanical interfaces was verified, and redundancy was added to the sealing systems, the agency said.

The agency also referred to updated non-destructive testing during different phases of integration and transportation of the stage, as part of the strengthened checks.

The PSLV is a four-stage launch vehicle that has been one of India's principal routes to orbit for Earth-observation, scientific and commercial satellites. A successful static firing is a necessary qualification step, but it does not by itself reproduce the full conditions of an operational launch, and ISRO has not announced the number or dates of the further tests, or the mission that will use the revised stage.