F-47 vs GCAP: America’s Sixth-Generation Fighter and the Tempest Programme

The F-47 and the Global Combat Air Programme (GCAP) are the two Western sixth-generation fighters with funded development contracts and firm dates. One is an American national programme run by the US Air Force and Boeing. The other is a partnership of the United Kingdom, Italy and Japan, built by a joint company called Edgewing and often still known by its British name, Tempest.

They are aimed at similar threats and share a taste for size and range. This comparison sets out what each side has disclosed, where they differ, and why the F-47 is unlikely to be sold to the countries building GCAP.

The short answer

The F-47 is further ahead and better funded. Boeing has been building the first aircraft since 2025, the Air Force plans a first flight in 2028, and development money is running at about $5 billion a year. GCAP will fly a technology demonstrator by the end of 2027, but the fighter itself is not due in service until 2035.

GCAP has something the F-47 lacks: partners who share the cost and control the design. For Britain, Italy and Japan that independence is the point of the programme.

F-47 and GCAP side by side

For more on each, see what the F-47 is and our explainer on the Global Combat Air Programme.

Where GCAP stands

GCAP was created in December 2022 by merging Britain’s Tempest project with Japan’s F-X, with Italy as the third partner. A treaty followed in 2023, and a government body, the GCAP International Government Organisation, now runs the programme from Reading in England. Industry is organised through Edgewing, owned in equal thirds by BAE Systems, Leonardo and Japan Aircraft Industrial Enhancement Co.

The programme moved into full development in 2026. A first contract worth £686 million was awarded in April, and on 1 July the three governments signed a £4.6 billion contract running to the end of 2027. Britain’s Defence Investment Plan sets aside £8.6 billion for the programme to 2029-30. BAE Systems’ flying demonstrator, powered by two Typhoon engines, was about three-quarters built in mid-2026 and is due to fly by the end of 2027.

How the aircraft compare

Both are large. The F-47’s stated combat radius of more than 1,000 nautical miles is matched by British claims that the GCAP fighter will be able to cross the Atlantic on internal fuel, with an internal weapons load about twice that of an F-35A. Both programmes have concluded that range and payload matter more than agility.

Their priorities differ in emphasis. The F-47 is described first as an air-superiority fighter, as we explain in F-47 vs F-22. GCAP is presented as a multirole aircraft with a heavy strike load, reflecting the needs of three air forces that have no bomber fleet. Both are designed to work with uncrewed aircraft, though the United States is further along with its Collaborative Combat Aircraft.

Neither side has released detailed performance data. The F-47’s shape is concealed. GCAP’s models show a large delta wing with twin tails, but the final design is not fixed.

Sovereignty is the dividing line

The countries behind GCAP are all F-35 operators, and their experience of depending on American software and support is one reason they are paying for their own aircraft. They want to be able to modify it, arm it with their own weapons and export it without asking Washington.

That is why the F-47 is not a realistic alternative for them. Trump said in 2025 that allies were calling to buy the aircraft and suggested a toned-down export version, and Japan was reported to have been offered it. No sale has followed. GCAP has also gained from the collapse of the rival Franco-German FCAS fighter in June 2026, which leaves it as Europe’s only funded sixth-generation programme.

Which will be better?

It is too early to say. The F-47 should arrive about five years sooner and has the larger budget, but it also carries the risk of flying before its engine is ready, as described in F-47 engine. GCAP has more time to mature its technology and three treasuries to satisfy. The two are more likely to fly alongside each other than against each other.

Frequently asked questions

What is GCAP?

The Global Combat Air Programme is a joint project of the United Kingdom, Italy and Japan to build a sixth-generation fighter for service from 2035. It is often called Tempest in Britain.

Is the F-47 better than GCAP’s fighter?

Neither has flown, so it cannot be judged. The F-47 is further ahead in schedule and funding; GCAP offers its partners control over the design.

Which will fly first, the F-47 or GCAP?

A British GCAP demonstrator is due to fly by the end of 2027, and the F-47 in 2028. The demonstrator is a test aircraft, not the final fighter.

Will Britain or Japan buy the F-47?

There is no sign of it. Both are committed to GCAP, and the United States has not formally offered the F-47 for export.

When will GCAP enter service?

The partners describe 2035 as a fixed date.

Who builds GCAP?

Edgewing, a joint venture owned equally by BAE Systems, Leonardo and Japan Aircraft Industrial Enhancement Co.