The H3 rocket is tracking for a maiden flight toward the end of 2020. MHI conducted hot-firing tests of the rocket's LE-9 first-stage engines early this year. Credit: JAXA

WASHINGTON — Mitsubishi Heavy Industries still expects to conduct the maiden flight of Japan’s H3 rocket this year, notwithstanding the coronavirus pandemic. 

The next-generation rocket, which started development in 2014, will launch as MHI’s last mission of the year, following three H2A missions carrying satellites and one H2B mission to resupply the International Space Station. 

“[The] coronavirus situation is quite unclear and may get worse globally,” Ko Ogasawara, MHI’s vice president and general manager for space systems, said by email March 23. “This might affect our plan in the end. But again, today, we will do our best to attain our schedule.”

As of March 25, Japan had reported 1,300 confirmed cases of COVID-19, with 45 recorded deaths, according to disease trackers at Johns Hopkins University. The country’s numbers have stayed low despite being one of the first countries outside China with a confirmed case of the disease. Nonetheless, the International Olympic Committee agreed March 24 to postpone the 2020 Tokyo Olympic Games to 2021.

Ogasawara, in an interview at the Satellite 2020 conference in Washington earlier this month, said MHI has remained productive on H3 despite many employees required to telework amid school closures and other social distancing measures taken to slow the spread of the novel coronavirus. 

MHI completed first-stage hot-fire tests with the H3’s LE-9 liquid-oxygen and liquid-hydrogen engines early this year, he said. A hot-fire test of the rocket’s second stage, which uses a single LE-5B engine, is scheduled for May or June, he said. 

Integrated testing of the full rocket will follow, leading up to a final first-stage static-firing at Japan’s Tanegashima Island spaceport just prior to launch, he said. 

“At the end of this year we are now planning to launch H3,” he said. The launch will carry JAXA’s Advanced Land Observation Satellite, ALOS-3, he said. 

Funded by the Japan Aerospace Exploration Agency, H3 is MHI’s answer to SpaceX’s Falcon 9, Arianespace’s Ariane 6, and other launch vehicles that can launch upward of 6,500 kilograms to geostationary transfer orbit. H3 will replace the current H2A and H2B launch systems MHI fields. 

MHI halved the number of engine components in the LE-9 engine compared to the H2A’s LE-7A, Ogasawara said. That process involved 3D printed parts, robotic manufacturing assistants and a switch from hydraulic to electrically driven engine valves, he said. 

MHI focused on shedding cost from the LE-9 in order to make the H3 rocket compete more effectively on price with other launch systems. Ogasawara said MHI introduced robotic manufacturing assistants to support other elements of rocket production, such as tanks. 

MHI has completed one launch this year, orbiting an Information Gathering Satellite for the Japanese military using an H2A rocket in February. JAXA announced MHI will conduct an H2B launch May 22 to deliver the Kounotori-9 cargo shuttle to the International Space Station.

The company plans two other H2A missions before H3’s debut — the UAE’s Emirates Mars Mission and Inmarsat’s I-6 F1 communications satellite. Ogasawara declined to say when each launch would occur. 

Ogasawara said the Kounotori-9 mission is the ninth and final launch of the H2B, a high-power variant of the H2A that has two LE-7A first-stage engines instead of one. 

Once the Kounotori-9 launch is complete, MHI will modify the H2B launchpad at Tanegashima to enable H3 missions, he said. The launchpad modifications will support different attach points between the H3 rocket and launch tower, and changes to rocket exhaust pathways to reduce acoustic vibration during liftoff, he said. 

While H3 is designed to complete all the missions the H2A and H2B handle, Ogasawara said MHI will keep flying H2A rockets until 2023, providing a transition window for conservative customers like the Japanese military. Once all H2A missions are completed, MHI will modify the H2A launchpad at Tanegashima for H3 as well, enabling a higher launch cadence. 

With both launchpads, MHI hopes to launch up to 10 H3 rockets a year, with up to six of those being for commercial customers, Ogasawara said. MHI has announced one commercial H3 mission for British satellite operator Inmarsat, scheduled for 2022. 

Ogasawara said most H3 launches will use a version of the rocket equipped with two LE-9 engines and up to four-strap on solid-rocket boosters. A heavier configuration with three LE-9 engines will be reserved mainly for Japanese military missions, he said. 

A much larger “triple core” variant of the H3 designed to support NASA’s lunar Gateway is still under consideration, he said.

Caleb Henry is a former SpaceNews staff writer covering satellites, telecom and launch. He previously worked for Via Satellite and NewSpace Global.He earned a bachelor’s degree in political science along with a minor in astronomy from...