Japan’s New H3 Rocket Fails

Japan’s launch of its new H3 rocket with an earth observing satellite onboard failed tonight when the second stage apparently failed to ignite. The first stage seemed to perform perfectly and separated from the second stage, but it is not clear what happened after that. Ground controllers sent a destruct command to the second stage when it became evident a failure of some sort had occurred.

Expectations were high for this evening’s launch at 8:37:55 pm Eastern Standard Time (March 7, 10:37:55 am in Japan) after a scrub last month at literally the last moment. In that case, the main engines ignited as planned at T-6.3 seconds, but the automated control system detected an anomaly and halted the launch before the Solid Rocket Boosters fired, which should have happened at T-0.4 seconds. The Japan Aerospace Exploration Agency, JAXA, said tonight the problem was not with the rocket, but an electrical cable connection to the launch pad.

Today’s countdown proceeded smoothly and liftoff was on-time.

Everything seemed to go well during the flight of the first stage. The Solid Rocket Boosters separated as planned and the first stage completed its work and separated from the second stage.

Confirmation of second stage ignition did not follow, however, and the velocity of the rocket, shown on JAXA’s live broadcast, clearly was diminishing not accelerating as the clock passed T+9 minutes. The webcast posted a message to stand by.

Minutes later, mission control reported “Destruct command has been sent because no possibility of achieving the mission.”

It is surely a disappointment to JAXA, its industry partners, and the earth observing and disaster management communities that were awaiting data from the Advanced Land Observing Satellite-3 (ALOS-3) also known as Daichi-3.

Japan has expansive plans for the H3, not just replacing the H-II series with a rocket that is more competitive on the world market, but can be used to take payloads as far as the Moon in support of the NASA-led Artemis program. In the nearer term, it will launch the upgraded HTV-X cargo spacecraft to the International Space Station. HTV, or Kounotori, is the largest of the ISS cargo resupply vehicles. The last of the original HTV series, HTV-9, was launched in 2020.

The H3 program began in 2014 and this first launch was supposed to take place in 2020, but Mitsubishi Heavy Industries experienced challenges developing the LE-9 main engine — an expander bleed cycle engine. The cause of today’s failure is not yet known, but initial indications are the LE-9s performed well, whatever happened after that.