Japan is studying a reusable rocket, but it won’t fly before 2030

Japan debuted the new flagship H3 rocket in March, capping a decade-long, nearly $1.5 billion development effort to replace a launch vehicle that has been in service for more than 20 years. The H3's upper stage failed to ignite a few minutes after liftoff, causing the rocket and its Earth observation payload to crash into the Pacific Ocean. Officials in the Japanese government are already plotting the replacement for the H3 rocket, which had a goal of cutting in half the cost per launch of the H-2A launcher, a workhorse for Japan's space program. But the H3 is based on a single-use expendable design, like nearly all legacy rockets. The H3 design aims to achieve these cost savings through modernized manufacturing techniques and commonality in hardware with Japan's smaller Epsilon rocket family. The Japanese government updated its basic plan on space policy in June with language endorsing the development of a reusable rocket to follow the H3. Now, the Japan Aerospace Exploration Agency (JAXA) has tapped Mitsubishi Heavy Industries for joint studies on the next-generation launcher, which would have a recoverable and reusable first-stage booster, Space News reported this week. There's no design yet for this still-unnamed rocket. A JAXA spokesperson told Space News that engineers haven't settled on a fuel. It could be cryogenic methane, the fuel favored by most companies developing new reusable launch rockets, or Japan could stick with liquid hydrogen, the super-cold fuel used on the H-2A and H3 rockets. The space policy document released by Japan's Cabinet Office in June outlined several key technologies necessary for the country's next-generation rocket. Those included rocket reuse tech, innovative materials, methane-fueled propulsion, and modernized production capabilities. Japanese policymakers wrote that the new rocket, replacing the H3, would start flying in the 2030s. "By reusing parts ... we will improve launch frequency and transportation capacity, and reduce launch costs," Japanese government officials wrote in the policy plan. SpaceX's demonstration of the benefits of reusable rockets has inspired others to pursue similar capabilities. Rocket Lab, the US-New Zealand company that operates the light-class Electron launcher for small satellites, has successfully recovered boosters and recently reused an engine from a previous flight. In the coming months, Rocket Lab plans to reuse an entire set of nine booster engines on a launch. The company is developing a new rocket named Neutron with a booster stage designed from the start to be entirely reusable. Blue Origin and several other companies also may be a few years away from reusing boosters on their orbital-class rockets. United Launch Alliance's new Vulcan rocket is powered by Blue Origin-built BE-4 engines. ULA plans to eventually recover the engines and reuse them but doesn't plan to retrieve the entire first stage of the Vulcan rocket. Other rocket builders, like Europe's ArianeGroup, went all-in with a new expendable rocket, similar to Japan's approach with the H3. Europe's expendable Ariane 6 rocket won't fly until next year, at the earliest. The European Space Agency and European industrial partners are in the early stages of designing a reusable methane-fueled engine that could lead, in the longer term, to a reusable replacement for the Ariane 6. But like Japan's new reusable rocket study, a follow-on to the Ariane 6 would likely not fly until 2030 or later.

Taking the pulse of Japan’s rocket programs

Like many countries, Japan views independent access to space as a strategic imperative. Like other large spacefaring nations, Japan prefers to launch its spy satellites and scientific probes on homemade rockets. From the government's perspective, attracting international or commercial customers is a bonus for any institutional-led rocket program. But a higher volume of launches should drive down the marginal cost of each flight, feeding a virtuous cycle that would, theoretically, apply downward pressure on prices and lead to higher reliability. The H3 rocket was largely funded by the Japanese government through JAXA. Japan seems to be taking the same approach for the new reusable rocket study now underway. Mitsubishi Heavy Industries, which is joining JAXA on the study, is the prime contractor for the H-2A and H3 rockets. MHI operates the H-2A on a commercial basis after JAXA relinquished control of the program following the rocket's initial test flights. By any measure, Japan's core rocket family has been a technical success. The H-2A rocket, along with the related H-2B launch vehicle, has flown 56 times since 2001 with a success rate greater than 98 percent, putting those rockets in elite company on the global stage. There are three H-2A rockets left in Japan's inventory, and the H-2B is now retired. But MHI did not secure much commercial business for the H-2A and H-2B rockets. Only three of its 56 launches to date were procured by customers on a competitive basis. The others were missions for the Japanese government. Japanese officials hoped the less costly H3 would lure more commercial business to the Japanese launch industry, but only one commercial customer has signed up for an H3 launch. In an environment where SpaceX and other emerging rocket companies with reusable vehicles offer bargain prices, the Japanese launch industry has a lot of work to do to remain relevant in the international market. The H3 rocket comes in several configurations, the most powerful of which features strap-on solid rocket boosters to give the launcher a payload capacity of up to 6.5 metric tons to geostationary transfer orbit, a destination for many large communications satellites. SpaceX's Falcon 9 rocket has a similar lift capability to the same orbit. Japan's space agency hasn't set a target date for the next H3 test launch after the rocket's first failure in March. There are other Japanese rockets besides the H-2A and H3. The Japanese company IHI, working in partnership with JAXA, has developed a small solid-fueled rocket called Epsilon to carry a little more than a ton of payload into low-Earth orbit. Japanese startups built on an entrepreneurial model similar to SpaceX and Rocket Lab are also vying to carve out a place for themselves in the launch market. One of those companies, Interstellar Technologies, unveiled a design for a large reusable rocket named Deca earlier this year. Interstellar has successfully launched a suborbital rocket into space and is working on a small orbital-class rocket as an intermediate step before the much heavier Deca vehicle.