PSLV Third Stage Test: Key Facts for UPSC

PSLV third stage passed a ground static test on 12 November 2026, following anomalies in two missions. The test adds a new development to India’s space technology coverage.

Quick answer: The Indian Space Research Organisation (ISRO) successfully tested the PSLV third stage at Sriharikota on 12 November 2026. It revised the solid motor after anomalies in two Polar Satellite Launch Vehicle (PSLV) missions. The changes cover the nozzle, mechanical interfaces, seals and quality procedures; further tests are planned.

What happened in the PSLV third stage test?

ISRO successfully conducted a ground static test of the revised third-stage motor at the Static Test Facility. The facility is at the Satish Dhawan Space Centre in Sriharikota, Andhra Pradesh.

In a static test, engineers fire a motor while it remains secured on the ground. Thus, they can examine its performance without launching a vehicle.

Why did ISRO revise the stage?

ISRO reviewed the configuration after third-stage anomalies in PSLV-C61/EOS-09 and PSLV-C62/EOS-N1. The review covered design margins, raw material acceptance, assembly procedures and quality checks.

A design margin provides allowance beyond expected operating requirements. Therefore, improving it can help a component withstand demands during operation.

What changes did ISRO make?

ISRO strengthened the motor configuration and updated its inspection and assembly procedures.

• Nozzle configuration: ISRO introduced improvements to increase design margins.
• Interfaces and seals: It strengthened mechanical interfaces and added redundancy to sealing systems.
• Checks and procedures: It updated raw material acceptance, assembly procedures and quality checks.
• Non-destructive tests: It updated tests during integration and transportation; such tests assess materials or components without damaging them.

ISRO also verified the adequacy of the design margins. However, it plans further tests following detailed analysis and review of the test data.

Why does the test matter for space missions?

The test checks a revised motor intended for a launch vehicle that ISRO seeks to bring back on track. However, a successful ground test is not itself a flight demonstration.

For Prelims, distinguish a launch vehicle, which carries a payload into space, from the satellite it carries. PSLV has four stages; its first and third use solid propulsion, while its second and fourth use liquid propulsion. For comparison, see CBL’s coverage of the GSLV-F18 and the NavIC mission and the GISAT-1A Earth observation satellite.

Source: The Hindu Sci-Tech, 13 November 2026

Asked in UPSC: Previous Year Questions

Prelims Practice Corner

Mains Practice Questions

Frequently Asked Questions