H2A Rocket: Pass Advanced Technology on to Next Generation

Editorial

15:59 JST, July 1, 2025

Japan’s mainstay large H2A rocket was successfully launched for the model’s final flight, concluding its operations. The rocket, which was highly reliable, made a significant achievement as it played an important role that will go down in history as part of Japan’s space development.

The H2A was jointly developed by the Japan Aerospace Exploration Agency and Mitsubishi Heavy Industries Ltd. The first rocket was launched in 2001, and the 50th rocket was used in the latest launch. During this time, the only failure was the sixth launch in 2003, giving the H2A a success rate of 98%. It can be said that this figure is one of the highest for rocket launches.

There were only a few major delays in launches, which was another selling point of the H2A, since it was easy for the companies that asked for launches to work out their schedules.

Throughout a quarter of a century in operation, the H2A has carried many satellites into space, including the Hayabusa2 probe, which brought back sand samples collected from the surface of an asteroid; the SLIM lander, which was Japan’s first successful lunar lander; and government information-gathering satellites.

Launching satellites is related to national security. It is becoming increasingly important for Japan to maintain its own rockets for launching satellites, rather than relying on other countries to launch them. It is significant that Japan has maintained its own launch capability with the H2A.

On the other hand, the H2A cost about ¥10 billion per launch. Due to its inability to compete on the global market, there have been few contracts with overseas firms.

In recent years, the global market for space development has been changing drastically. More companies in the private sector are entering the space business, and there is a growing need to win orders for satellite launches at low prices.

The U.S. company SpaceX, which has cratered prices in the rocket launch market, has set the trend. The company’s success in developing reusable rockets has led to launches at lower costs and at shorter intervals.

The role of the H2A will be taken over by the H3 rocket, which was successfully launched last year. With the H3, the aim is to keep the cost of launches down to ¥5 billion through various measures, including using automobile parts. The frequency of launches will also increase from the H2A’s average of about twice a year.

Through these improvements, it is hoped that a system will be put in place to receive orders from customers worldwide.

It is also essential to map out a strategy that looks beyond the H3. The development of a new engine for the H3 faced difficulties. This is probably because the technology has not been sufficiently passed down to the next generation as a result of the lack of opportunities to develop rockets since the H2A was designed.

The development of a successor rocket to the H3 should begin as soon as possible in order to ensure that the technology is passed on to the next generation. Startup companies overseas are pursuing bold development without the fear of failure. Japan, too, must foster a mindset that allows for a certain degree of failure and seeks to increase the speed of development.

(From The Yomiuri Shimbun, July 1, 2025)