How ISRO's Watchful Eye Saved the Axiom-4 Mission from a Critical Failure

In what could have turned into a costly and dangerous failure, India’s space agency ISRO played a pivotal role in detecting and averting a major technical anomaly during the preparations for the Axiom-4 mission, the latest private astronaut launch to the International Space Station. The mission, operated by Axiom Space using SpaceX’s Falcon 9 rocket, included onboard India’s own Group Captain Shubhanshu Shukla, making it a matter of both national and international significance.

The incident unfolded in early June 2025, when a routine pre-launch static fire test of the Falcon 9 rocket was conducted at NASA’s Kennedy Space Center. While the test appeared successful to the untrained eye, it was Indian scientists from ISRO — present as part of the mission support team — who first flagged something unusual: a minor leak in the LOX (Liquid Oxygen) feed system of the rocket's first-stage booster.

At first, the anomaly was dismissed by some engineers on the U.S. side as within tolerance. SpaceX teams proposed using a purge system workaround, aiming to move forward with the launch timeline. But ISRO, led by its highly respected Chairman V. Narayanan, didn’t let it slide. Drawing on deep experience in cryogenic propulsion and engine diagnostics, Narayanan and his team insisted the leak could pose a serious risk during actual launch — especially given the cryogenic temperatures and high-pressure dynamics of the Falcon 9's systems during ascent.

ISRO’s concerns weren’t limited to the leak. During the same static test session, another issue emerged: a thrust vector control (TVC) actuator malfunction on one of the Falcon 9's engines. While SpaceX teams worked to troubleshoot it, it was again the Indian engineers who pushed for a full low-temperature verification and complete actuator replacement, rather than temporary patches.

It was a bold stand, especially on foreign soil and in the high-pressure context of a commercial launch window. But ISRO held its ground. Narayanan’s insistence on absolute crew safety and full structural integrity checks forced a delay in the launch — a decision that, in hindsight, may have saved the mission.

Eventually, SpaceX complied. The problematic TVC actuator was replaced, and the liquid oxygen leak was re-evaluated using ISRO’s recommended methods. The team also conducted cold-weather testing of the engine plumbing, which validated the seriousness of the issue. Repairs were made onsite, avoiding the need to roll back the rocket to the Vehicle Assembly Building, a move that would have meant weeks of delay.

Once these safety-critical issues were addressed, launch preparations resumed — until another unrelated delay struck: a pressurization anomaly in the ISS Zvezda service module, temporarily preventing any new spacecraft from docking. With that resolved, the Axiom-4 mission finally lifted off on June 25, 2025, carrying a four-person crew including Shubhanshu Shukla, who became the first Indian private astronaut in space.

But without ISRO’s intervention, things might have played out very differently. Had the Falcon 9 launched with the unresolved leak or faulty actuator, it could have led to a catastrophic engine failure mid-flight, endangering the crew and jeopardizing international partnerships.

This episode also reflects a deeper reality in India’s evolving space diplomacy. Once seen only as a launch provider or budget satellite builder, ISRO is now asserting itself as a global-level technical authority — one capable of making life-saving calls on missions it does not even directly manage.

Chairman V. Narayanan, long known for his work in cryogenic engine development, has now earned further recognition for leadership under pressure and technical foresight, with international experts privately praising ISRO’s role in the rescue.

For SpaceX and Axiom, ISRO’s pushback was a sobering reminder: partnerships with spacefaring nations like India come not just with ambition, but with expertise, precision, and an uncompromising commitment to safety.

As India eyes its own crewed mission, Gaganyaan, and expands its collaborations in space tourism and science, ISRO’s actions during the Axiom-4 mission will be remembered not just for saving a rocket, but for setting a global standard of vigilance in human spaceflight.