print PRINT


H3 rocket engine development reaching crucial stage

  • November 25, 2017
  • , Nikkei , p. 6
  • JMH Translation

By Satomi Inomata


The main engine development of Japan’s next-generation launch vehicle, the H3, which is aiming for a first launch in fiscal 2020, is reaching a crucial stage. Combustion tests have been completed to confirm basic functions and will move on to more rigorous testing to determine performance and lifespan. Whether or not Japan can succeed in development could determine the future of the nation’s space industry, as many foreign competitors are developing next-generation rockets.


A massive silo-like building is found atop a hill at the end of a narrow mountain road within Tanegashima Space Center, Kagoshima Prefecture. It is the combustion test site for H3’s main engine, the LE-9, where the engine is secured onto steel scaffolding.


Initial combustion tests have been completed to confirm basic functions. The engine will undergo next phase of testing this winter at full capacity, including durability tests. Based on the test data, efforts to improve the engine will continue until spring of next year. The goal is to complete the launcher’s engine in time to achieve a first launch during fiscal 2020.


“We need affordability more than high-performance in a launcher,” says Teiu Kobayashi, the technical head of the Japan Aerospace Exploration Agency (JAXA) driving the development team. “We hope to set global standards with Japan-made technology.”


JAXA and Mitsubishi Heavy Industries are developing the H3 as a replacement for the current main H2A rocket. It is the first large-scale development since the H2, the prototype to the H2A, which was first launched in 1994. The agency’s goal is halving launch prices that currently cost 10 billion yen and to drive Japanese rocket technology to lead global standards.


Main engines are critical to propelling rockets into space. They are made by assembling more than 100,000 components, requiring a high degree of precision and durability. “The development of H3 cannot move forward without first completing the main engine,” says Masashi Okada, JAXA’s project leader.


It is said among engine developers that their work is cursed by “evil spirits,” as many technical issues often arise during the combustion testing phase. The H2 took two extra years to complete due to a series of unexpected accidents during development. Although durability issues were found among some components during recent combustion tests, there were no significant obstacles. “We are very relieved,” reflects Kobayashi.


The key feature of the LE-9 is its adoption of a novel combustion system that has a much simpler structure than the H2A with 20% fewer number of parts, which improves its reliability in unforeseen circumstances. It also emits more combustion gas, raising its propulsion capacity by 40%. In addition, the development process has been streamlined to prevent technical conflicts in advance through running simulations prior to assembly. This new method eliminates the need to experiment through trial and error, saving development time and costs.


A string of next-generation rockets made by foreign players are slated to debut in and around 2020 when the H3 is scheduled for its first flight. France’s next-generation Ariane 6, which has undergone cost-cutting efforts like the H3, has succeed in shortening the lead time between order placement to launch by a third by innovating its manufacturing processes. Russia has developed common components that can be cross utilized among its Angara models. Russia is leading the global development race with successful flight tests under its belt.


It remains to be seen whether the H3 will win many contracts amidst intensifying global competition for satellite launchers. The future of Japan’s space industry may be determined by the development of the LE-9.


  • Ambassador
  • Ukraine
  • COVID-19
  • Trending Japan