The PSLV-C62/EOS-N1 mission, launched on 12 January 2026 from the Satish Dhawan Space Centre in Sriharikota, has encountered a significant anomaly towards the end of its PS3 stage, marking another setback for ISRO's workhorse rocket.

The vehicle lifted off at 10:18 a.m. IST following a 22.5-hour countdown, carrying the primary EOS-N1 earth observation satellite and 15 co-passenger payloads developed by start-ups, academia, and international partners.

ISRO Chairman Dr V Narayanan confirmed that performance remained as expected up to the close of the third stage, but unusual disturbances in the vehicle's roll rates led to a deviation in the flight path.

A detailed data analysis is now underway to pinpoint the root cause of this issue. The PSLV, a four-stage rocket comprising two solid propellant stages and two liquid ones, relies on precise sequencing for successful payload injection.

The anomaly disrupted this critical phase, preventing the planned deployment of EOS-N1 and 14 co-passengers into a Sun Synchronous Orbit, as well as the subsequent restart of the PS4 stage for de-boosting the KID Capsule into a re-entry trajectory. Both the PS4 stage and KID Capsule were slated to re-enter Earth's atmosphere, impacting the South Pacific Ocean.

EOS-N1, developed under the commercial auspices of NewSpace India Limited (NSIL), serves strategic earth observation needs, underscoring its importance to India's defence and surveillance ecosystem. The mission's co-passengers reflect growing international collaboration and private sector involvement in Indian space launches.

These include Theos-2, a joint Thailand-UK earth observation satellite from SSTL (UK); multiple payloads from India's Dhruva Space such as CGUSAT, DSUSAT, MOI-1 (with Takeme2Space), LACHIT, and Thybolt-3 (with Don Bosco University); Munal from Nepal's Antharkshya Pratishtan and India's MEA; KID by Orbital Paradigm (Spain) and RIDE! (France); Edusat, Uaisat, Galaxy Explorer, Orbital Temple, and Aldebaran-1 from Brazil's AlltoSpace; Sanskarsat from Laxman Gyanpith; and AyulSat from OrbitAid, both Indian ventures.

This failure comes mere months after the PSLV-C61 mission on 18 May 2025, which also faltered due to a third-stage anomaly during the attempted launch of EOS-09. That incident halted payload deployment, raising immediate questions about recurring vulnerabilities in the PS3 stage, which uses a liquid propellant engine for velocity augmentation. Back-to-back PSLV mishaps represent a rare stumble for ISRO, which has historically achieved a success rate exceeding 95 per cent with over 50 missions since the rocket's debut in 1993.

The implications extend beyond technical troubleshooting, touching on ISRO's commercial credibility and India's burgeoning private space sector. NSIL, as the commercial arm, markets PSLV rides to global customers, and consecutive failures could erode confidence among international payloads like those from Thailand, UK, Brazil, Nepal, Spain, and France. For domestic start-ups such as Dhruva Space and OrbitAid—key players in India's defence innovation ecosystem—these losses disrupt revenue streams and technology validation timelines, potentially delaying indigenous capabilities in satellite constellations and SMALLSAT deployments.

From a strategic defence perspective, EOS-N1's role in earth observation aligns with India's priorities in border surveillance, maritime domain awareness, and disaster management, areas increasingly intertwined with aerospace advancements tracked by professionals in DRDO, HAL, and private firms like Tata Advanced Systems. A prolonged grounding of PSLV variants could strain NSIL's order book, forcing reliance on GSLV or LVM3 for lighter payloads, though these lack PSLV's proven SSO precision. Moreover, with India's push towards industrial-scale launches amid AMCA, Gaganyaan, and hypersonic programmes, such anomalies highlight the need for accelerated failure investigations and redundancy in propulsion systems.

ISRO's response will likely prioritise transparency, as evidenced by Dr Narayanan's prompt update. Historical precedents, like the PSLV-C37 partial failure in 2016 due to heat shield issues, show ISRO's ability to rebound swiftly through rigorous reviews. Yet, two PS3-related failures in under eight months suggest deeper systemic factors—possibly injector dynamics, attitude control glitches, or propellant sloshing—that demand metallurgical or simulation-based scrutiny. The space agency has convened experts, with preliminary findings expected soon, potentially averaging data from telemetry, onboard sensors, and radar tracks.

Broader geopolitical ripples merit attention. As India strengthens defence ties with QUAD partners and Russia for tech transfers, PSLV reliability underpins soft power in space diplomacy. Nepal's Munal and Thailand's Theos-2, backed by Indian aid, exemplify this; their losses could temper enthusiasm for future collaborations.

Meanwhile, China's recent Long March successes and US SpaceX dominance intensify competitive pressures, urging ISRO to integrate AI-driven prognostics and private sector collaboration for efficiency.

In the near term, ISRO faces choices: implement quick PS3 fixes for upcoming manifests, pivot to SSLV for SMALLSATS (despite its own teething issues), or fast-track PSLV-XL upgrades. Success here bolsters India's self-reliance under Atmanirbhar Bharat, vital for UAV swarms, quantum-secured communications, and next-gen reconnaissance.

Agencies