Exclusive | Safety First, Launch Later: ISRO Chief Explains Axiom-4 Mission Delay And SpaceX Rocket Leak

By Surabhi Gupta

New Delhi: A major snag has forced a delay for India's first private astronaut mission to reach the International Space Station (ISS) via the Axiom-4 mission. A previously scheduled launch date of June 11, 2025, aboard SpaceX's Falcon 9 rocket has been deferred due to a liquid oxygen (LOx) leak discovered during a routine check.

The delay halts the much-anticipated expedition of Indian Air Force Group Captain Shubhanshu Shukla, who was to be India's second astronaut in space (after Rakesh Sharma). Shukla was chosen as part of a four-member international crew in the Axiom-4 mission to the ISS, with the mission planned and executed by Axiom Space, marking a historic partnership between SpaceX, ISRO, and the US-based private space company Axiom Space.

Safety First: Enter ISRO

India's space agency, ISRO, has played a big role in postponing the launch until the LOx leak on the Falcon 9's booster stage is well-carefully addressed. V Narayanan, Secretary of the Department of Space and Chairman of ISRO, confirmed the seriousness of the situation in a detailed statement to ETV Bharat. He indicated that while LOX leakage was a serious issue, it could be managed, provided that all QA and QC protocols were followed.

"The time required for rectification will depend on the type of leakage. If it were LH2, the process would typically take longer as it can cause an explosion," he explained.

Narayanan, a renowned cryogenic propulsion expert, is stationed at the Kennedy Space Centre in Florida, overseeing the technical aspects of India’s participation. He played a pivotal role in developing India’s indigenous cryogenic engine technology and is one of the foremost authorities in handling LOx and LH2 propellants.

Narayanan further elaborated on the challenges posed by hypersonic missiles, stating that their velocities far exceeded the response time of available radars and defence systems, which needed activation through tracking radars. "Even the velocities of intercepting missiles and their tracking system responses fall short of hypersonic missiles," he noted.

"As part of the launch vehicle preparation, a seven-second hot test was conducted on the Falcon 9 booster stage at the launch pad," he said. "It is understood that the LOx leakage was detected in the propulsion bay during the test."

He stated that following discussions between the ISRO team and experts from Axiom and SpaceX, the decision had been made to correct the leak and conduct the necessary validation tests before approving the launch. As a result, the Axiom-4 mission, originally scheduled for June 11, 2025, to send the first Indian Gaganyatri to the ISS, had been postponed.

After multiple high-level deliberations, the agencies jointly agreed that safety must take precedence, especially when human lives are involved. The repair of the LOx leak, followed by rigorous revalidation, has been deemed mandatory before rescheduling the launch.

Indian Concerns Over On-Pad Repairs

ISRO officials, quoted anonymously in Indian media, expressed concern that SpaceX was attempting to repair a LOx leak on a human-rated rocket directly on the launch pad. “In India, we will never allow such a thing to happen, especially when humans are in the loop,” said a senior ISRO scientist. The sentiment underscores India’s conservative and safety-first approach to human spaceflight.

SpaceX, in a statement, said, “The launch has been called off to allow additional time for SpaceX teams to repair the LOx leak identified during post static fire booster inspections. Once complete - and pending Range availability - we will share a new launch date."

Axiom-4: India’s First Ticket to the ISS

The Axiom-4 mission, organised by Houston-based Axiom Space, is a commercial human spaceflight project taking astronauts from multiple nations to the ISS for scientific and educational purposes. India purchased a seat for Group Captain Shubhanshu Shukla at a cost of approximately Rs 550 crore.

The crew includes astronauts from the United States, Hungary, and Poland, with Shukla serving as the mission pilot. The 14-day mission to the ISS is designed to carry out experiments in microgravity, conduct outreach activities, and prepare astronauts for future long-duration flights.

The mission is India’s first human spaceflight partnership with international private companies and marks a significant diplomatic and scientific leap. The country is also independently preparing for its maiden indigenous crewed mission, Gaganyaan, scheduled for launch in 2025-26.

Impact of the Delay

While the delay is a setback, there are several remaining launch windows available. Experts say that until June 30, there are favourable orbital alignments for the Axiom-4 mission. If unresolved by then, another window may open in mid-July. Beyond that, the ISS traffic becomes congested, which may push the mission further down the calendar.

Given the critical nature of human spaceflight and the reputational stakes involved, ISRO and the Indian government are expected to tread carefully. Sources say that India’s insistence on thorough testing and international best practices may delay the mission, but will ultimately safeguard its long-term goals in space exploration.

The immediate next step is to identify and fix the LOx leak in the Falcon 9 rocket. Once repaired, the booster stage must undergo another round of validation tests to ensure it is flight-worthy. Only after full assurance from SpaceX, Axiom, and ISRO will a new launch date be finalised.

For now, the Indian astronaut and his crew remain on standby in Florida, continuing with their mission rehearsals and training.

As the world watches, India is taking no shortcuts. The delay may have pushed back a historic milestone, but it has reaffirmed India's steadfast commitment to safety, international collaboration, and scientific excellence in human spaceflight.