The Japanese government is making final adjustments with the United Kingdom on its participation in the F-X program for a next-generation fighter. It is seeking to close a deal by March 2022.
The Japanese Acquisition, Technology and Logistics Agency (ATLA) selected Rolls-Royce to assist them in the development of the powerplant for their future sixth-generation fighter. Japan already had an advanced prototype engine for the new fighter, the XF9, and Rolls-Royce’s assistance will likely focus on improving it to meet the required specifications.
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According to Yomiuri local media, the United Kingdom will also be involved in the development of the air intakes and the rear fuselage. From the Japanese Ministry of Defense, they consider that involving British companies in the design aspects of the fuselage that are related to the performance of the engines, is the most rational action. These parts are also important because they are closely related to the aircraft’s stealth performance and overall shape.
Tokyo expects to have a cooperation framework in place by next March. A prototype will be built from 2026 and flight testing is expected to start from 2030.
The UK, together with its partners (Italy and Sweden) is working on its own sixth-generation fighter project, the Tempest. And given that its engineers will be involved in key aspects of the design of the future Japanese F-X, it is likely that the two aircraft will end up partly resembling each other.
In fact, it is no secret that London is actively seeking to entice Japan to join «team Tempest» (there are even calls to merge this program with FCAS) which is why they were very open about sharing sensitive technical information with their Japanese counterparts.
But Tokyo is still determined that the Mitsubishi F-3 (the designation the aircraft is likely to receive), which is intended to be the replacement for the Mitsubishi F-2, will be a project developed by and for Japan.
However, understanding that its defense strategy is intrinsically linked to that of the U.S., it is also seeking U.S. technical assistance (such as Lockheed Martin) to help design other parts of the aircraft so that the product of the F-X program will be a weapon system that is highly interoperable with those of the U.S.
