LONDON — Japan could be the next partner nation for the trinational, British-led next-generation fighter program, an official hinted at the DSEI arms trade show in London.

The United Kingdom, Sweden, and Italy are jointly developing cutting-edge technologies to feed into the Future Combat Air System effort. The FCAS is to eventually lead to a core fighter aircraft and a raft of new capabilities alongside it by 2035.

Since 2020, Japan has partnered on elements of the program, but military and industry officials at the biennial DSEI conference in London hinted that the relationship could develop further within the next few years.

The program — also referred to as Tempest, and separate from the Franco-German-Spanish effort also known as FCAS — is working with Japan on the technological initiative, said the U.K. program director, Air Commodore Johnny Moreton.

“We’ve been in negotiation, conversations and some pilot projects — nothing necessarily too complex at the moment,” he said while moderating a Wednesday panel on the program’s advantages through international alliances at the conference.

In July, the Japanese government announced that the two countries had pledged to jointly develop new engine technologies that could inform both the London-led FCAS program, and Tokyo’s F-X effort to build a new sixth-generation fighter jet.

“We’re doing a joint engine viability study with Japan at the moment, and that’s quite exciting,” Moreton said. “They have an F-X program that has a very similar time frame to us, 2035; the threat is very similar to the one that we are anticipating, and in terms of an industrial nation, clearly they sit at the top table, as do we.”

The United Kingdom and Japan might extend the partnership beyond engine technologies, into electronic warfare and radar capabilities, he noted. However, those are “very much at a minor stage at this point,” he added.

Last year, the U.K., Sweden and Italy signed a memorandum of understanding to collaborate on the FCAS project, involving their national industry partners BAE Systems, Saab and Leonardo, respectively.

While Moreton emphasized that the British military’s work with Japan was an “exploratory partnership” during the panel, the static display of a possible FCAS cockpit just feet away from the podium on the DSEI exhibition floor had four national flags hanging distinctly above it.

The close, if still unofficial, partnership between the United Kingdom and Japan on FCAS-related technologies demonstrates that “where we see opportunity across the world, we are prepared to embrace” it, Moreton said.

While the FCAS allies and their industry teams are working together to develop the next-generation technologies, the concept of “freedom of modification” — where each country has the ability to make its own changes to the future aircraft and systems — also remains paramount.

“We want to be able to upgrade, advance [and] develop our capabilities ourselves, and as sovereign countries inside the partnership, each partner has that goal,” Moreton said.

Japan’s participation is a clear example of that dynamic, said Guglielmo Maviglia, senior vice president for Leonardo’s Tempest program.

“Trying to tightly bound all of this [effort] into a single partnership, I think, is a mistake anyway,” he said on the panel. “So leaving the flexibility for other partners to join is really important, and Japan provides us with our first test of that.”

On July 29, the British Defence MInistry announced a £250 million (U.S. $346 million) contract to launch the FCAS concept and assessment phase with its “Team Tempest” partners. The nation plans to spend about £2 billion on the program over the next four years, the government said. The contract was awarded to a U.K. industry team led by BAE Systems, which includes Rolls-Royce and the British arms of Leonardo and MBDA.

The FCAS team will continue this phase over the next several years, with plans to define and begin the design of FCAS, mature system technologies, invest in a skilled workforce, and secure the digital and physical infrastructure needed by 2024.

“The purpose of this phase is to look at the concepts [and] make an assessment of the program,” Moreton said. “And then, in late ‘24, go to our governments — Italy, Sweden, U.K. in this case, and potentially Japan — and say: ‘This is the program. This is what we can deliver. This is the timeline and the capability.’ And we’ll move forward from there.”

Vivienne Machi is a reporter based in Stuttgart, Germany, contributing to Defense News' European coverage. She previously reported for National Defense Magazine, Defense Daily, Via Satellite, Foreign Policy and the Dayton Daily News. She was named the Defence Media Awards' best young defense journalist in 2020.

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