JAXA releases preliminary results of investigation into December 2025 H3 rocket launch failure
JAXA yesterday released the preliminary results of its investigation into upper stage failure during the December 2025 launch of its H3 rocket.
Previously the agency had indicated it believed the cause was linked to the separation of the rocket’s payload fairings. This new report changes that conclusion:
After liftoff, the No. 8 H3 rocket sustained damage to the section where the Michibiki No. 5 positioning satellite was mounted, when the satellite cover, called fairing, was separated.
In addition, the fuel tubing of the rocket’s second-stage engine was damaged, presumably causing combustion to stop earlier than planned, JAXA said in a progress report on its investigation into the failure at a meeting of a subgroup of a science ministry panel.
As the section was damaged, the satellite was no longer attached to the second stage of the rocket. The satellite fell off when the first stage separated.
In other words, as the fairings released, the satellite apparently deployed, damaging the fuel feed to the upper stage engine. It is as yet unclear whether the deployment system worked as intended, but did so prematurely, or if it failed entirely, allowing the satellite to fall away once the fairings separated.
At the moment Japan has no launch capability. Both of JAXA’s rockets, the H3 and the Epsilon-S are grounded due to launch failures. Meanwhile, the country has only recently begun to develop private launch companies, none of which are ready to launch.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon or from any other book seller. If you want an autographed copy the price is $60 for the hardback and $45 for the paperback, plus $8 shipping for each. Go here for purchasing details. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
JAXA yesterday released the preliminary results of its investigation into upper stage failure during the December 2025 launch of its H3 rocket.
Previously the agency had indicated it believed the cause was linked to the separation of the rocket’s payload fairings. This new report changes that conclusion:
After liftoff, the No. 8 H3 rocket sustained damage to the section where the Michibiki No. 5 positioning satellite was mounted, when the satellite cover, called fairing, was separated.
In addition, the fuel tubing of the rocket’s second-stage engine was damaged, presumably causing combustion to stop earlier than planned, JAXA said in a progress report on its investigation into the failure at a meeting of a subgroup of a science ministry panel.
As the section was damaged, the satellite was no longer attached to the second stage of the rocket. The satellite fell off when the first stage separated.
In other words, as the fairings released, the satellite apparently deployed, damaging the fuel feed to the upper stage engine. It is as yet unclear whether the deployment system worked as intended, but did so prematurely, or if it failed entirely, allowing the satellite to fall away once the fairings separated.
At the moment Japan has no launch capability. Both of JAXA’s rockets, the H3 and the Epsilon-S are grounded due to launch failures. Meanwhile, the country has only recently begun to develop private launch companies, none of which are ready to launch.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon or from any other book seller. If you want an autographed copy the price is $60 for the hardback and $45 for the paperback, plus $8 shipping for each. Go here for purchasing details. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News