Some 40 years after the first flight of the EAP demonstrator in August 1986 – a new experimental stealth aircraft is being built in the NW of England to get the UK ‘match fit’ for GCAP. TIM ROBINSON FRAeS was of the first journalists to see it.

The BAe EAP performs a spirited take-off at Farnborough Airshow in 1986. (BAE Systems)
Some four decades ago, on 8 August 1986 a sleek shape blasted into the air at British Aerospace Warton, Lancashire- with the test pilot at the time, Dave Eagles, at the controls – who famously took it to Mach 1.1 on its first-ever flight The one-off fighter jet was the Experimental Aircraft Programme or EAP – a British-designed and developed demonstrator that would test and de-risk key capabilities and technologies that would then feed into the multinational Eurofighter Typhoon programme – now the backbone of European air power. Noted another BAe EAP test pilot Chris Yeo “My overriding memory of the aircraft was the performance. It's got such aggressive performance that you have to be on top of it all the time. You cannot let the aircraft get ahead of you”.
Today, 40 years at BAE Systems Samlesbury Systems Warton, history is being repeated with a new experimental aircraft, the combat air flying demonstrator now in final assembly. Like the EAP before it, this is UK-funded and developed stealth demonstrator that will, this time feed into the tri-national Global Combat Air Programme – which is set to deliver a ‘sixth-generation’ combat platform in the 2040s and beyond.
Media exclusive

View of the ducting inside the centre fuselage section. Hiding the engine fan blades from the front, yet keeping the airflow clean is major challenge. (BAE Systems)
In mid-June, this journalist was one of the first media to see the current progress on the assembly of this demonstrator. Being put together in a corner of the Typhoon facility, the size of the prototype under build is significant - with integrating the serpentine LO intakes and ducting that change cross-section almost across the entire length, one of the key challenges. With the UK not having flown a British-designed and built combat aircraft in 40 years the demonstrator is making sure that BAE and the wider UK combat air sector is “match fit” for GCAP says Tony Godbold, Future Combat Air Systems (FCAS) Delivery Director at BAE Systems. Says Godbold: “We are pushing boundaries, testing new things, trying new things out in engineering and manufacturing to get ready and match fit for the main programme.”
Already this demonstrator effort is paying off with Godbold saying this work, which includes digital design, model-based systems engineering and additive manufacturing, has “saved ourselves a number of years” on GCAP. The next milestones this year will see structural testing of the wing, final assembly of the front, centre and rear fuselage, which will then be moved to Warton to be mated with the giant wings. On this current schedule, the aircraft will be ready for flight by the end of 2027. The exact date of the first flight will be finalised nearer the time to optimise learning and maximum benefit to GCAP.
The top takeaways

Latest rending of the CAFD. (BAE Systems)
- It is a large aircraft – the sheer size of the centre fuselage is staggering – with a capacious weapons bay
- Judging by a human to scale, each wing has a span of approximately 12-14ft – and one of the largest composite parts ever built for a military aircraft in the UK. Three wings are being built – one exclusively for structural testing.
- Fit tolerances of parts– already incredibly precise for Eurofighter manufacturing, will be taken to new levels for a stealth aircraft requiring extreme levels of external smoothness.
- The demonstrator is pioneering new technology – such as advanced additive manufacturing - including hot isostatic pressing (HIP) of structural parts. This not only makes for zero waste but cuts lead time for casting of large titanium parts from four years to one year.
- Auto coding of flight control software – has sped up FBW and handling development with 300+ virtual test flights in the simulator – meaning the aircraft controls are now ahead of where they would be in previous projects. Says Godbold: “that complete loop has allowed us to mature the design flow control system much earlier than we before before, but not only that, develop a digital twin to that system.”
- Integration of the stealthy LO engine ducting so that airflow arrives at the engine face in a clean state as possible after passing down the serpentine ducting that blocks radars from seeing the fan blades – a major focus and and challenge.
- Hints of world-beating UK tech in LO: “We are not sure the physics exist for this yet - that's the level that we are shooting for within this whole programme”
- The demonstrator is also making BAE relearn old skills – with partners in Europe having built the wings for Eurofighter and Tornado, BAE is relearning its wing manufacturing skills from the Hawk and Harrier days.
- Though the aircraft will be larger than Eurofighter, twin R-R EJ200 engines for the demonstrator will still give it crisp performance, with a test pilot speaker at last year’s RAeS FCAS Summit revealing it still has fighter style handling, despite its large size.
- Name for the Combat Air Flying Demonstrator still TBC – with BAE insiders admitting the challenge of finding something suitably and hasn’t been used before. Given the ‘storm’ theme in UK combat aircraft – Hurricane, Whirlwind, Tornado and Lightning it is a far bet that it will continue this trend – although there is general agreement that in RAF service, GCAP will be known as Tempest.
- BAE hint that this national UK demonstrator could have wider applications to feed into the GCAP programme, with Godbold saying “there's other potential experimentation opportunities as we align this with GCAP”
- The demonstrator is saving time, resources and increasing skills and knowledge according to BAE. Notes Godbold: “We have learned things doing this activity that, without it, would have significantly given us a problem down the line. We have probably saved ourselves a number of years of development risk”.
Summary

The demonstrator at Farnborough in 2028? (AI generated)
Having seen the fuselage under assembly at Samlesbury – this is far from a paper or CGI concept. The programme is already making progress in building experience, skills and getting (along with similar efforts with Rolls-Royce and the Leonardo that are developing the powerplants and sensors) the UK combat air sector ‘match fit’ for GCAP. Despite recent headlines over UK defence funding and chaos – this programme is attracting the best and the brightest in the UK, to continue Britain's long-standing heritage of world-beating fighter development that traces back over 100 years through iconic names like the Camel, Spitfire, Harrier and Typhoon.
Says Godbold: “I grew up having textbooks with EAP in it and it was one of the inspirations that drew me to the industry and a career in engineering. So having that complete circle in an area of country that I grew up not too far away is fantastic. It’s one of those moments where you pinch yourself sometimes you're part of the team, part of the organisation that is doing this again and it is a 40 year gap”, adding: “Sometimes the hair stands on the back of your neck, because we've got a real aircraft taking shape here”.
26 June 2026