Another Axiom-4 mission delay: What caused SpaceX Falcon 9’s oxygen leak before Shubhanshu Shukla’s historic spaceflight?

Axiom-4 mission postponed again due to Falcon 9 fuel leak, launch halted after liquid oxygen leak during Falcon 9 test

The launch of the Axiom-4 (Ax-4) mission to the International Space Station (ISS) has been postponed again, after a liquid oxygen (LOX) leak was discovered in the propulsion bay of the Falcon 9 rocket during pre-launch testing. The mission was scheduled to lift off on 11 June 2025 at 5:30 PM IST.

SpaceX shared the update on X, saying, “Standing down from tomorrow’s Falcon 9 launch of Ax-4 to the ISS to allow additional time for SpaceX teams to repair the LOX leak identified during post-static fire booster inspections.”

The team will now carry out repairs and run validation tests before announcing a new launch date.

ISRO confirms delay, repair work underway

ISRO Chairman Dr V Narayanan also confirmed the delay on X, explaining that a seven-second hot test was conducted on the launch pad as part of regular preparations. During this test, engineers identified the leak.

He added that ISRO, Axiom Space, and SpaceX experts jointly decided to correct the issue and validate the system before moving forward with launch approval.

The Ax-4 mission has already faced several delays, having been pushed from May 29 to June 8, then June 10, and most recently to June 11. and then now.

Shukla’s historic spaceflight postponed

The mission is especially important for India, as it will carry Group Captain Shubhanshu Shukla, the first Indian to visit the ISS and the second Indian astronaut in space after Rakesh Sharma in 1984.

Shukla will serve as the pilot of the Ax-4 mission. Peggy Whitson from the United States will command the crew, with Slawosz Uznanski-Wisniewski (Poland) and Tibor Kapu (Hungary) joining as mission specialists.

Science experiments on food, nutrition, and algae in space

Once aboard the ISS, Shukla will conduct experiments on food and nutrition in space, in a collaboration between ISRO, the Department of Biotechnology (DBT), and NASA.

The research will focus on the growth and behaviour of edible microalgae in microgravity and space radiation. The goal is to develop self-sustaining life support systems for long-duration space missions.