The BAE Systems Tempest is a proposed sixth-generation fighter aircraft that is under development in the United Kingdom for the Royal Air Force (RAF).

This was followed by an announcement in December 2022 of the Global Combat Air Programme (GCAP); a collaboration between Italy, Japan and the UK for a sixth-generation fighter aircraft.

[4] The Sunak ministry engaged in productive and positive "initial conversations" with Saudi Arabia about their desire to join the programme.

The key elements of that strategy are:[10][11] The 2018 UK Air Strategy document describes combat air as "An aircraft, manned or unmanned, whose prime function is to conduct air-to-air and/or air-to-surface combat operations in a hostile and/or contested environment, whilst having the ability to concurrently conduct surveillance, reconnaissance, electronic warfare and command and control tasks.

According to the MOD press release, the demonstrator's development is already underway at the BAE Systems facility in Warton near Preston, England and it has already been flown in simulators, with a predicted prototype test flight by 2026-2027.

[25] On 19 July 2019, Sweden and the United Kingdom signed a memorandum of understanding (MoU) to explore ways of jointly developing sixth-generation air combat technologies.

[31] At the virtual Farnborough Airshow in July 2020, Defence Secretary Ben Wallace announced seven new companies were joining the Team Tempest consortium: GEUK, GKN, Collins Aerospace, Martin Baker, QinetiQ, Bombardier in Belfast (now Spirit Aerosystems) and Thales UK, along with UK universities and SMEs.

[33] The involvement of Italy and Sweden was confirmed by the signing of a trilateral MoU with the UK, called Future Combat Air System Cooperation (FCASC), on 21 December 2020, "defining general principles for co-operation on an equal basis between the three countries".

[35] In October 2023 the Italian Ministry of Defence presented new budget for Parliament approval, which increases the investment forecast to €7.7 billion by 2037.

[38][39] Discussions to combine efforts on Tempest with Japan's own Mitsubishi F-X fighter project as a means to cut development costs began as early as 2017.

[14][19] Tempest will feature a virtual cockpit shown on a pilot's helmet-mounted display[43] using a Striker II unit,[18] and an adaptive cycle engine that utilises composite materials and improved manufacturing process to be lightweight and have better thermal management while still keeping costs low.

[44] The aircraft has a slightly raised rear fuselage section, to accommodate “S-shaped” ducting behind its twin-engine inlets, to reduce its frontal radar cross-section.