Rare third-stage failure: ISRO aborts mission mid-air as radar satellite fails to reach orbit 

India's trusted workhorse rocket, the Polar Satellite Launch Vehicle (PSLV), suffered a rare failure early Sunday when its 101st mission was aborted mid-flight due to an anomaly in the third-stage propulsion system.

The PSLV-C61 lifted off at 5:59 a.m. IST from the Satish Dhawan Space Centre in Sriharikota, carrying the 1,696 kg EOS-09 radar imaging satellite. However, around 203 seconds into the flight, the third stage — powered by a solid hydroxyl-terminated polybutadiene (HTPB) motor — underperformed, forcing the Indian Space Research Organisation (ISRO) to terminate the mission.

The satellite, meant to enter a 524 km sun-synchronous polar orbit, failed to reach space. EOS-09 was equipped with a C-band Synthetic Aperture Radar (SAR) and was intended to bolster India’s all-weather surveillance capabilities, especially for border security and disaster response.

“This marks only the third full failure for the PSLV in 63 launches, and the first since 2017,” ISRO Chairman V Narayanan confirmed during the live broadcast, noting the deviation occurred during the PS3 phase.

Initial telemetry points to an underperformance in the solid-fueled third stage, though the exact cause — whether linked to nozzle issues, propellant flow, or structural concerns — remains under investigation. ISRO has constituted a failure analysis committee to examine the PS3 stage’s test data and manufacturing records.

With this setback, India’s plans to accelerate deployment of a 52-satellite surveillance constellation face a temporary pause. The mission had been particularly significant as ISRO’s 101st overall launch and a continuation of its 58 successful PSLV missions since 2017.

Following standard safety protocols, both the rocket’s fourth stage and the payload were destroyed after the anomaly was detected. The debris is expected to fall in safe, uninhabited zones.

Despite the failure, ISRO officials remain confident about recovery. The agency has previously bounced back from similar setbacks in under six months and still plans four more PSLV launches this year.