Japan’s Next-Generation H3 Rocket has Engine Troubles

JAXA has delayed maiden H3 flight to 2020.
Credit: MHI/JAXA

Japan has announced that the maiden flight of the country’s next-generation launch vehicle has been delayed after a “technical problem” plaguing the rocket’s first-stage engine was discovered.

In a brief September 11 press release, the Japan Aerospace Exploration Agency (JAXA) revealed that a technical problem had been discovered with the LE-9 rocket engine that will power the first stage of the country’s H3 launch vehicle. According to JAXA, the problem will push the maiden launch of the vehicle from 2020 to 2021 and the vehicle’s second flight from 2021 to 2022.

The H3 launch vehicle is set to take over from the country’s H-2A and H-2B rockets, which have been Japan’s primary path to space for nearly two decades.

Designed to be an extremely flexible launch vehicle, the H3 will offer two types of fairings, two or three first-stage engines, and four, two, or no solid rocket boosters. This will enable the vehicle to launch a wide range of payload sizes to an impressive array of orbits.

The LE-9 is a liquid-fueled engine powered by liquid hydrogen and liquid oxygen. According to a December 2017 Mitsubishi Heavy Industries (MHI), the prime contractor for the H3, report, the engine is unique in that it’s the world’s only first stage engine that does not feature an auxiliary combustion chamber. This reduces cost and complexity. With a less complicated engine that costs less, you can produce a launch vehicle that is affordable and reliable.

As recently as March this year, MHI completed a series of LE-9 hot first tests and gave no indication that any issues had been discovered. With the announcement earlier this month, JAXA did not reveal what issues arose between March and September to prompt the delay in development.

Andrew Parsonson is a space enthusiast and the founder of Rocket Rundown. He has worked as a journalist and blogger for various industries for over 5 years and has a passion for both fictional and real-life space travel. Currently, Andrew is the primary writer for Rocket Rundown as we look to expand our reach and credibility.