Launch of Axiom-4 mission carrying India’s Shubhanshu Shukla delayed again after rocket leak setback

The much-anticipated launch of the Axiom-4 (Ax-4) space mission, carrying Indian Air Force pilot Shubhanshu Shukla to the International Space Station (ISS), has been postponed for a fourth time — this time due to a technical snag in the Falcon 9 rocket being used by SpaceX.

Originally scheduled to lift off from NASA’s Kennedy Space Center in Florida at 5:30 PM IST on June 11, the mission was delayed after a liquid oxygen (LOx) leak was detected in the propulsion system of the rocket's first-stage booster during post-static fire inspections.

“Standing down from tomorrow’s Falcon 9 launch of Ax-4 to the space station to allow additional time for SpaceX teams to repair the LOx leak... Once complete — and pending range availability — we will share a new launch date,” SpaceX said in a post on X.

The mission was initially slated for Tuesday but had been pushed to June 11 due to unfavorable weather. Now, with the recurring leak and ongoing repairs, SpaceX has yet to confirm when the launch will proceed.

India's ISRO weighs in

ISRO’s chairman V. Narayanan confirmed the cause of the delay, saying the issue surfaced during a seven-second hot test of the Falcon 9’s booster stage. “LOx leakage was detected in the propulsion bay during the test. Based on discussions with Axiom and SpaceX experts, it has been decided to correct the leak and conduct validation tests before proceeding,” he stated.

The Falcon 9 rocket being used is a reused booster — its second flight after a Starlink mission earlier this year — raising additional concerns about refurbishment and reliability.

More technical troubles surface

William Gerstenmaier, SpaceX’s vice-president for build and flight reliability, revealed that the LOx leak had appeared during the rocket’s previous mission but wasn't fully addressed during refurbishment.

“We are also installing a purge system to mitigate any remaining leakage, if detected again during launch,” he said. He also noted a thrust vector control issue with Engine 5, which has now been resolved.

Next available launch window unclear

Although another launch opportunity exists on June 12, officials remain uncertain whether repairs will be completed in time. NASA’s Dana Weigel, ISS program manager, assured that the Ax-4 mission has multiple backup windows through June 30 and into mid-July.

“This is the reality of human spaceflight. Dry runs and checks are critical — you learn something new every time,” Gerstenmaier added, emphasizing the complexity of space operations.

If successful, the Ax-4 will mark a historic first: Shubhanshu Shukla will become the first Indian astronaut to visit the ISS under a commercial mission.