Japan Aerospace Exploration Agency (JAXA)
Reusable Rocket Tests Do Not End with Breaking Things
The competitiveness of reusable rockets will be determined not by flashy launches, but by how quickly signs of failure found during testing can be fed back into the next design. In September 2026, Japan Aerospace Exploration Agency (JAXA) and Future Space Transportation System began work to improve the accuracy of analysis models using test data on landing mechanisms and engines. If vehicles can be safely recovered and refurbished, then flown frequently, university satellite plans could also be rearranged to match the results of the next experiment.
A reusable rocket cannot simply be used again as soon as the vehicle that flew has been recovered. Engineers must determine whether the first stage, which has endured the loads and heat of launch before returning and landing, can withstand another flight. In Japan, space transportation services using reusable rockets have not yet become a reality. There is also no operational foundation for flying frequently and cheaply.
The Difficulty of Connecting Test Data to Design
To check whether landing equipment and engines have any abnormalities, engineers need to test actual vehicles. But if they have to rebuild them substantially after every test, the process takes time. This is where digital models come in. They recreate the condition of a vehicle through calculations and predict where the next loads will be placed.
However, models cannot replace physical tests. They can be used to make design decisions only after being compared with data from actual tests, having their discrepancies corrected, and being validated. Reusable rockets also require an operating process in which the vehicle is inspected and refurbished after landing, then flown again at short intervals.
Feeding the Results of Breaking Things to Verify Them into the Next Design
Japan Aerospace Exploration Agency (JAXA) and Future Space Transportation System Co., Ltd. (ISC) began a co-creation activity in September 2026 concerning a space transportation service business using reusable rockets. Under the J-SPARC framework, ISC will provide an overview and design models of the ASCA series of vehicles that it aims to develop for reference.
ISC will test the landing mechanism and engines, and give JAXA data on deformation and strain, as well as the flow rates and pressure in piping. JAXA will use the data to improve the accuracy of analysis models that recreate and predict the condition of the vehicle. The aim is to develop general-purpose modeling technology that can be used not only for ASCA, but also by universities and space ventures.
Through RV-X and CALLISTO, JAXA has accumulated knowledge of modeling technology useful for landing-leg design and detecting abnormalities during inspections. The challenge this time is to improve accuracy by comparing the models with test data and develop them into models that do not depend on a specific vehicle. If this effort advances, the speed at which signs of failure can be fed back into the next design will become a competitive advantage for reusable rockets.
Where the Time Spent Waiting for a Launch Will Change
If the models are sufficiently validated and become usable in the design and operation of actual vehicles, it will be possible to reduce the number of tests that break things to verify them, as well as design rework. In university laboratories, plans to put observation equipment assembled by students on satellites could be rearranged to match the results of the next experiment, rather than being tied to launch opportunities that come only once every few years.
There is, however, a condition for that scene to become reality. It will be necessary not only to improve the accuracy of the models, but also to actually recover, inspect, refurbish, and fly the vehicles again at short intervals. This activity is intended as a step toward realizing that operation, preparing a way to put things broken during testing to use in the next design.