The Global Combat Air Programme is Writing Cheques that Defence Can’t Cash

Lofty ambitions: UK Prime Minister Rishi Sunak visits RAF Coningsby in December 2022 following the announcement of the GCAP programme. Image: Reuters / Alamy

The development of a next-generation fighter as part of the Global Combat Air Programme risks being held back by unrealistic cost and investment estimates. Either it must be funded properly, radically downscaled in ambition, or not done at all.

Whether the ambitions of the UK’s Tempest – now the Global Combat Air Programme, or GCAP, following the recent cooperation agreement with Japan – include a new piloted fighter as the core air vehicle or not is the critical question for the RAF and the Ministry of Defence (MoD) in the Defence Command Paper refresh and the next Defence Review. Multiple statements by senior political and military leaders referring to a ‘next-generation fighter’ strongly point to the programme heading in this direction. It is the assumption permeating the collective Defence establishment, and has been heavily implied in presentations by those in the MoD and industry who have been tasked with taking the programme forwards. However, the fighter ambition poses significant challenges for affordability and practicality, especially given that Tempest is now directly competing for funding with the requirement to regenerate frontline RAF combat capability to deter Russia and meet NATO commitments over the coming decade. Put simply, the funding committed or even hinted at publicly so far by participating countries falls well short. The UK Combat Air budget as it exists currently also offers no capacity to fund a credible ‘sixth’ or even fifth generation fighter programme. The public refusal to acknowledge the likely costs of developing a competitive fighter risks becoming another example of the chronic MoD and defence industry habit of using overly optimistic cost estimates to lock in politically binding commitments on major projects. Before committing to any main gate decision, it is important that a realistic cost and military capability estimate for GCAP is undertaken to avoid distorting vital RAF and wider MoD planning at a crucial crossroads.

Looking to previous experience, in 2011 the National Audit Office estimated the total cost to the UK of developing, procuring and upgrading the RAF Typhoon fleet at £22.95 billion in cash terms. When adjusted for inflation using the government’s GDP Deflator toolset with an assumed mid-point spend of financial year (FY) 2005–6, this results in a figure of approximately £34.54 billion in FY 2022–23 terms. Within this figure, development costs alone were £6.7 billion, or £11.11 billion in inflation-adjusted terms today, assuming a mid-point spend for development of FY 2000–1. This was just the cost for the UK, with Germany contributing a similar amount and Italy somewhat less. However, even the smallest partner, Spain, estimated its costs for development and acquisition of the Eurofighter [Typhoon] by April 2015 at €12.84 billion – which, assuming this estimate had been adjusted for 2015 cash terms, would be approximately €15.22 billion today when adjusted for Spanish Eurozone inflation. In other words, the development and procurement of Typhoon cost the four core partner states somewhere in the region of £100 billion in FY 2022/23 terms. This cost estimate excludes weapons development, fleet operating costs, infrastructure and personnel training.

By contrast, for the entire GCAP system-of-systems, the UK has so far committed to spending £2 billion during the initial research and scoping phases, and Italy has only committed to €1.8 billion, with an ambition to ultimately spend another €2 billion by 2034. Recent UK announcements of £250 million and £656 million funding tranches have only covered the contract allocation of the previously committed £2 billion, not new money. Perhaps more worryingly, the most up-to-date public version of the MoD’s Major Projects Portfolio lists the total estimated programme cost up to the forecast retirement date of 2070 at just £10.69 billion. This total would include through-life ownership, mid-life upgrade and operating costs, so a significant portion of it would not be allocated to funding initial development and acquisition.

Digital design, prototyping and testing techniques and a much closer and more collaborative relationship between the MoD and industry are central pillars of the GCAP plan. Policymakers and the public are regularly assured that these genuinely impressive advantages compared to previous generation efforts will allow GCAP to break the historical paradigm and deliver in ‘half the time and at half the cost’. If taken at face value, this would suggest that GCAP might be developed and procured at half the real-terms cost of Typhoon – still around £50 billion among partner states.

However, GCAP needs to be lethal and survivable in the threat environment of 2040–2070. Given the resulting advanced stealth, sensor, software and propulsion requirements, it is hard to see how an operationally credible next-generation fighter aircraft could cost significantly less to develop and procure than Typhoon did, even if one assumes that all the programme’s promises about paradigm-breaking cost reductions compared to previous generations of combat aircraft come true. To put the circa £100 billion development and procurement cost of Typhoon into perspective, in the current Equipment Plan, the entire Air Command portfolio budget to 2032 is £35.1 billion for equipment procurement and support, and the Strategic Programmes budget – most of which covers complex weapons and nuclear programmes – is £23.7 billion. Since GCAP is slated to declare initial operating capability in 2035, all the development costs and a majority of the acquisition cost would have to fall in the coming 15 years to successfully replace Typhoon for the UK and Italy and the F-15J for Japan by 2040.

A reasonable cost estimate for the UK to produce a potentially viable next-generation combat air programme will depend on how much other international partners such as Japan and Italy are able to commit. Japan is likely to be able to at least match the UK, but Italy is very unlikely to do so from a budget standpoint, especially since the Italian Air Force recently renewed its ambition to acquire its full intended fleet of 131 F-35s in light of the projected medium-term threat from Russia. Recent leaks purportedly from people with detailed knowledge of the programme have suggested that the UK and Japan currently expect to each shoulder around 40% of the programme cost, with Italy paying around 20%. If GCAP development and production costs are similar to those of Typhoon, which would be an impressive industrial achievement given the much greater necessary complexity and technological sophistication, this would imply a cost to the UK and Japan of £40 billion each in FY 2022–23 cash terms.

If it cannot seriously fund a competitive fighter programme, the UK should consider reducing the ambition of GCAP to instead develop a smaller and much cheaper fleet of UCAVs

GCAP as a fighter programme is also highly unlikely to produce a directly competitive product to the F-35 for RAF, Italian or Japanese operational requirements, or on the export market. Even if the UK, Japan, Italy and another partner like Saudi Arabia were all to hugely upscale their currently mooted funding and commit to serious development and acquisition budgets of around £25 billion each, the hard reality is that the primary competition Tempest will face is from the F-35. The latter’s development and production phases are costing the US $412 billion as of late 2022, with multiple international partners including the UK also having contributed billions in funding. In addition to the advantage of such enormous programme funding, Lockheed Martin was also able to leverage experience from developing multiple previous generations of successful US stealth combat aircraft like the F-22 Raptor and F-117 Nighthawk – experience that GCAP partners lack.

The development of the F-35 was certainly inefficient; the aircraft is far from mature; and it is hardly perfect as a system or a programme. However, the decades of expertise and the crushing weight of US investment in state-of-the-art sensors, weapons and electronic warfare (EW), as well as stealth and constant upgrade and retrofitting programmes through life have produced undeniable results. It is noteworthy that despite its higher operating costs, every single air force that has been allowed to assess the F-35 directly against its European and US competitors has ultimately opted for the F-35 – the operational capability in contested airspace is simply in a different class. If built, a GCAP fighter would not be competing against what the F-35 is now for orders, but against what the ‘Block 5+’ software and sensor-equipped version will be capable of in the late 2030s. The Block 4 upgrade programme alone will cost $15 billion for capability development, mid-life component upgrades and retrofit work. While this is an unwelcome additional cost for F-35 operators, it is also highly illustrative that this ongoing F-35 capability upgrade programme has significantly more funding behind it than all the GCAP development and acquisition funding announced by partners so far.

The Alternative UCAV Pathway

If it cannot seriously fund a competitive fighter programme, the UK should consider reducing the ambition of GCAP to instead develop a smaller and much cheaper fleet of stealthy unmanned combat aerial vehicles (UCAVs) specialised in the Suppression of Enemy Air Defences (SEAD) and penetrating ISTAR roles. Additional UK capabilities in these two mission sets would not only greatly improve medium- to long-term NATO deterrence credibility, but could also help make the UK an essential framework nation for any air campaign. More importantly, a UCAV fleet offers huge efficiency gains over piloted fast jets.

To operate piloted fast jets sustainably, a country needs to buy three to four airframes for every one that can be sustainably available at operational readiness. This is because fast jet fleets need an operational conversion unit and multiple frontline squadrons. These enable aircrew to train and then crew a squadron form cycle to manage readiness, deployment and rest periods. The fleet size and operating cost demands of training and sustaining aircrew are inescapable, even with ‘optionally piloted’ solutions. However, with a UCAV fleet, almost every airframe built can theoretically be held on the frontline. Furthermore, designs can be iterated more frequently and, hence, built in smaller, cheaper programmes with shorter timeframes, since airframes do not have to be sufficiently similar between ‘batches’ to allow pilots trained on one to fly the next without retraining. Most importantly, most of the actual flight time associated with fast jets is taken up by training sorties to maintain aircrew currencies and competencies, while UCAVs need only be flown a fraction as often to test systems, fly on operations or exercise with other force elements. This also gives them a mystique which makes them more valuable than a known and familiar capability in terms of deterrence of potential rival powers.

UCAVs designed with a low radar and IR signature for employment in contested airspace differ greatly from remotely flown ‘drones’ like the Reaper or Protector. This is because Russia’s modern EW capabilities can detect and deny or override the control links of a remotely piloted system, even if the latter is highly stealthy in terms of airframe. Consequently, UCAVs must be capable of fulfilling their primary (including lethal) tasks without real-time human control in-flight, so that they can operate in environments where the electromagnetic spectrum is highly contested. Of course, they need not be operated in such a way in situations short of war. However, a political decision to openly develop such systems would need to be made and justified to the public on the grounds that we already have many weapons which have automated target selection and engagement capabilities (such as anti-ship missiles, loitering munitions and advanced cruise missiles), and that it would be the commander’s legal responsibility to only use them in a mode appropriate to the situation. As in Ukraine currently, any hostile fire control radar, fighter aircraft or surface-to-air missile locking up a UCAV could be engaged without fear that it might be civilian.

The US has already developed and tested UCAVs with a high degree of in-flight autonomy, including target acquisition and weapons employment as early as 2005 in trials with the X-45 programme, and subsequently trials of the X-47B and others. China already has its Gonji [attack] GJ-11 UCAV in operational service with the People’s Liberation Army Air Force. The question is not whether the future of air combat includes UCAVs, but whether European powers will explicitly choose not to develop them for legal or ethical reasons. The UK’s existing Taranis UCAV demonstrator is highly stealthy, has weapons bays (not trialled), and could be adopted as a starting point for such work. The entire Taranis programme cost only £185 million, including a far more extensive flight test programme than initially intended.

The war in Ukraine shows what fighting without air superiority looks like – massed armies relying on ground-based artillery firepower for their lethality, with hundreds of thousands dead in the first year

A small UCAV force built up over time in small, iteratively improved batches would keep key skills alive at BAE Systems and elsewhere in the supply chain; offer much better value for money compared to a new fighter programme; and give the UK a leading position in shaping the emerging rules and norms in Europe and NATO on a key new technology. It would also provide a potential route for GCAP to merge with the Franco-German-Spanish SCAF/FCAS programme. SCAF/FCAS is likely to produce a fighter, but unlikely to produce much in the way of UCAV capabilities to operate as part of a system of systems, so if the UK, Japan and Italy produced a UCAV, there could potentially be grounds for merging to share cost, design and manufacturing responsibilities. Italian officials have repeatedly suggested that merging the programmes will ultimately be necessary, both from a cost point of view and to avoid mutually destructive competition for exports.

In conjunction with the existing RAF Typhoon fleet and additional F-35Bs beyond the 74 already funded (which could be more easily afforded without a full-scale fighter-development effort within Tempest), a small force of UCAVs with payloads of sensors, EW equipment and/or missiles offers the potential for great improvements in UK SEAD and penetrating ISTAR capabilities – and thus a route to ensuring the RAF remains the airpower partner of choice for the US Air Force and other NATO allies. It would also offer a potentially very attractive export product for various allies to augment their own existing fighter fleets/programmes, including Sweden, France, Germany, Japan and others. Compared to the fighter market, the stealth UCAV market is currently relatively uncontested.

A new fighter is still likely to be needed to replace Typhoon in the Quick Reaction Alert and air policing missions once the latter is retired in 2040, as highly automated UCAVs may still be technically and politically unsuitable for these sensitive tasks. However, if it committed to a UCAV programme as the output for GCAP, the UK could then ultimately choose to buy more upgraded F-35s, which would by then be in the middle of their anticipated lifespan for that purpose; or it could purchase whatever fighter the US has developed in the meantime; or it could buy the joint fighter that may result from a merger with the SCAF/FCAS programme.

The Opportunity Cost for the Coming Decade

The primary non-discretionary threat to the UK is, and is likely to remain, Russia in Europe and the North Atlantic. Because NATO’s warfighting doctrine relies on winning and exploiting air superiority for devastating battlefield effect, the most threatening part of Russia’s conventional military capability is its highly effective ground-based air defence system. NATO remains desperately short of Suppression/Destruction of Enemy Air Defences (SEAD/DEAD) and penetrating ISTAR capacity in the air domain. Both are critically important for joint-force viability, since the British Army – along with most European militaries – is not sized, equipped or doctrinally postured as the sort of massed artillery and armour force that can fight semi-effectively without large-scale air support. The war in Ukraine shows what fighting without air superiority looks like – massed armies relying on ground-based artillery firepower for their lethality, with hundreds of thousands dead in the first year and inconclusive battlefield results – despite Ukrainian heroism and Russian failures. Unless NATO wishes to build a joint force around large armies able to fight like this, then it needs air superiority.

Thus, the RAF needs to be able to play its part as the second largest non-US NATO air force (after France) in conducting the hard SEAD/DEAD mission to establish air superiority over Alliance territory that is contested by Russian forces as part of any future aggression. This requirement is particularly urgent given that US forces will be increasingly tied up by China in the Indo-Pacific, meaning that Europe may have to deal with any future Russian aggression with significantly less direct US military support. However, the current position on the RAF frontline for both Typhoon and F-35 is one where pilots are unable to regularly train in high-intensity tactics and scenarios and have inadequate weapon stocks for SEAD/DEAD in particular, and where availability is bottlenecked by serious shortfalls in spare parts and aircraft engineers. With an initial delivery date optimistically planned for 2035, Tempest offers no solutions to these problems in any meaningful timeframe. In its current form, however, it will still consume billions of pounds that are desperately needed to fund real operational solutions for the coming decades’ defence requirements.

Attempting to fund a new fighter from within the MoD equipment plan will greatly constrain the ability of the RAF to regenerate sufficient frontline capabilities to meet the UK’s NATO commitments and to deter and/or defeat the enduring Russian threat over the coming decade. The inadequate funding currently available also means that there is a great deal of risk being taken against the aim of developing GCAP itself as a competitive next-generation platform. Senior decision-makers need to face up to the real scale of investment required to do ‘a fighter’ properly, and either commit to investing tens of billions of pounds of new money; re-scope the ambition to a smaller and more efficient UCAV that might also be merged with SCAF/FCAS; or cancel the programme entirely.

The views expressed in this Commentary are the author’s, and do not represent those of RUSI or any other institution.

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Professor Justin Bronk

Senior Research Fellow, Airpower & Technology

Military Sciences

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