NAO review of the F-35 Lightning programme
The public spending watchdog has published its findings into our most sophsiticated aircraft, and the results are damning and worrying
The F-35 Lightning: the future of the RAF
Even though I’ve been immersed in defence for 20 years and more, in one way or another, some things still have the capacity to stagger me, and a reliable one is the cost of defence procurement, or, more specifically, the extent to which programmes exceed their initial predicted budgets. Equipment can end up costing many multiples of the original expected amounts, there is outrage, handwringing, excuses, promises to do better, then we all move of, and the same thing happens again. And no-one, but no-one, is ever held personally accountable, much less responsible.
So, here we have the Lockheed Martin F-35 Lightning. (As far as the manufacturers are concerned, it is the “Lightning II”, to recognise the Second World War-era Lockheed P-38 Lightning and the Cold War English Electric Lightning, and it “also draws parallels with a formidable force of nature”. Perhaps simply to be awkward, in Royal Air Force and Fleet Air Arm service, it is simply the “Lightning”.) It was the product of the Joint Strike Fighter (JSF) project which the UK joined at an early stage, signing a memorandum of understanding on November 1995 to become a formal partner, for which we agreed to pay $200 million, or 10 per cent of the concept demonstration phase. Additionally, in January 2001, the Royal Navy selected the JSF to fulfil its Future Carrier Borne Aircraft requirement, replacing the BAe Sea Harrier FA2 and Harrier GR7.
Lockheed Martin was awarded the contract for System Development and Demonstration for its X-35 in October 2001. The programme would be funded by the United States, by the UK as a Tier 1 partner, and by Italy, the Netherlands, Canada, Turkey, Australia, Norway and Denmark. There were major cost overruns and delays, with the cost per aircraft for an F-35A rising from $50 million in 2002 to $69 million in 2007 and $74 million in 2010. In 2012, Canada reviewed its commitment to buy the F-35 due to the increasing cost and in 2015 launched a new competition for the multi-role strike aircraft requirement.
The first F-35A flew in December 2006. The aircraft was designed to come in three variants: the standard F-35A, the lightest and cheapest type; the F-35B, capable of short take-off and vertical landing and capable of being deployed on aircraft carriers; and the full-spec carrier-capable F-35C, designed for catapult-assisted take-off and barrier-arrested recovery. There were myriad problems: the airframe of the F-35B was prone to premature cracking, the F-35C arrestor hook design was unreliable, fuel tanks were vulnerable to lightning strikes (ironically) and the sophisticated helmet display had problems. It had been anticipated that there would be a 70 per cent commonality of parts between the three variants, but it ended up as between 20 and 25 per cent.
The UK makes a troubled programme worse
Everything seemed to go wrong with the F-35, and by 2023 it was judged to be 80 per cent over budget and 10 years late. The UK initially planned to purchase 150 aircraft, then scaled that back to 138, ordering three test aircraft in 2009. In 2012, the Defence Secretary, Philip Hammond, re-committed to buying 48 F-35Bs for use on the Queen Elizabeth-class aircraft carrier. However, this was only after the requirement had been changed to fully carrier-capable F-35Cs as a result of the 2010 Strategic Defence and Security Review, then changed back under pressure from the chiefs of staff in May 2012. The government would not commit to a final overall figure until after the 2015 Strategic Defence and Security Review.
The order for 138 aircraft was confirmed in late 2015. The F-35B was to be used not only for the Royal Navy’s aircraft carriers, but by the Royal Air Force as a strike aircraft to replace the Panavia Tornado. The full complement of aircraft would be in service by the 2030s, with one permanent squadron being stood up in 2018 and another one or two in the 2020s. However, the Defence Command Paper of March 2021, Defence in a Competitive Age, did not repeat the commitment to acquiring 138 aircraft, saying only that more than the first tranche of 48 would be procured. The then-First Sea Lord, Admiral Sir Tony Radakin, indicated that the final number would likely be between 60 and 80.
The RAF received its first F-35B, intended for trials work, in July 2012. The aircraft entered service with 617 Squadron in April 2018, and the unit was declared combat ready in January 2019. The F-35B carried out its first operational mission in British hands in June 2019 when two aircraft patrolled over Syria as part of Operation Shader, and the first carrier-based operations were again by 617 Squadron from HMS Queen Elizabeth in June 2021, part of Operation Shader and Operation Inherent Resolve. One aircraft was lost during a routine deployment in the Mediterranean in November 2021, but the pilot ejected safely.
There are currently 37 F-35Bs in service with the Royal Air Force and the Fleet Air Arm (the two organisations operate the aircraft jointly), with another four under 17 Test and Evaluation Squadron based at Edwards Air Force Base in California as the Operational Evaluation Unit for the aircraft. In addition to 617 Squadron, they are operated by the Operational Conversion Unit, 207 Squadron, and by 807 Naval Air Squadron, though that unit is not yet deemed “deployable”. 47 more F-35Bs are expected next year, with another 15 by 2033. The RAF will also procure 12 F-35As, principally to be used for day-to-day training but also equipped to carry tactical nuclear weapons.
The National Audit Office: the news is not good
All is well, then? Alas no. Last week the National Audit Office (NAO) produced a report on The UK’s F-35 capability. It is absolutely damning of almost every aspect of the programme. So far the UK has spent £11 billion on acquiring the capability of the F-35 (an unkind and simplistic soul point out that that could be interpreted as £250 million per aircraft so far). Only a third of the aircraft are actually available to perform the tasks expected and required of them by the MoD’s commitments. Assuming we eventually acquire 138 aircraft and retain them in service until 2069, the MoD estimates the whole-life cost of the programme will be £57 billion, although its previous public forecast, which was based in 48 aircraft in service until 2048, was £18.76 billion. The NAO estimates it will cots £71 billion.
The F-35B is fundamentally an extremely advanced aircraft. The NAO states:
The capability provided by the F-35 across its multiple roles is significantly superior to any previous UK aircraft. It is a particular improvement in stealth capabilities, fusion of information from different sensors and electronic warfare capabilities. These combine to produce an aircraft many times more likely to survive and deliver operational effects in contested environments… it performs several roles, including suppression of enemy air defences, control of the air, electronic warfare, intelligence gathering and quick reaction alert responding to threats.
It acknowledges that F-35 pilots regard the aircraft as “absolutely cutting-edge”. However, it currently lacks some capabilities. Most obviously, it is not equipped to deliver any kind of stand-off weapon to strike ground targets at a safe distance. MBDA UK is developing the Spear 3 (Selective Precision Effects at Range), an air-launched cruise missile with a range of more than 90 miles which will be compatible with the F-35 as well as the Eurofighter Typhoon, the RAF’s other fast jet; this project was supposed to be completed in 2025, but the Minister of State for Defence Procurement and Industry, Maria Eagle, recently admitted in a Written Answer that Spear 3 would not be available operationally until the early 2030s.
Delivery of the aircraft has been appallingly slow. In both 2019 and 2024, only one additional aircraft was joined the fleet. In terms of actual deliveries compared to public commitments to acquire, the UK is performing abysmally set against other operators, with 38 of 138. Norway has all 52 of its aircraft, Australia has received 72 of its order of 100, the Netherlands has 40 of 58 and Denmark has 17 aircraft of a total of 27. Only Italy, with 33 aircraft of an intended 115, and Canada, which effectively cancelled and restarted its programme and has yet to receive any aircraft, are as far behind as the UK.
Slow delivery of aircraft is compounded by a shortage of qualified engineers and available pilots. The target date to achieve Full Operating Capability has already been deferred twice, and there will be further negative consequences from the Ministry of Defence’s decision to deploy two squadrons, 617 Squadron and 809 Naval Air Squadron, on HMS Prince of Wales as part of the carrier strike group exercise, Operation Highmast. As the NAO points out:
Because the second frontline squadron is not fully operational, having two full squadrons on the deployment requires borrowing aircraft and engineers from the 207 Squadron designated for training new pilots. This risks a reduction in training capability. There are likely to be fewer available aircraft following the deployment as aircraft need significant maintenance following deployment in the more corrosive maritime environment. Engineer availability will also reduce as staff take leave. The impact on operational readiness and force growth may last several months. Even if the MoD meets its FOC criteria, it will not yet have a force that can deploy sustainably.
All of these factors mean that, even with fewer than 40 aircraft delivered and in service so far—from a programme, remember, which the UK joined in 1995—there is currently very poor availability of aircraft, and therefore an inability by the RAF and FAA to meet the capability targets set by the MoD.
In 2024 the UK F-35 fleet achieved approximately half of the MoD’s target for mission capable rate—meaning the amount of time aircraft could fly and perform at least one of the seven F-35 mission sets. It did not come close to the target in any individual month. The UK F-35 fleet achieved approximately one third of the MoD’s target for full mission capable rate—the time that aircraft could fly and perform all required missions. This was despite the UK setting a target for its fleet significantly below the JPO target for the global F-35B fleet.
The RAF also had far lower availability than other F-35 operators, especially the United States Marine Corps, the F-35B variant’s most prolific user. There was one particularly shocking detail:
Between October 2024 and January 2025, the UK F-35 fleet had aircraft unavailable to perform any missions because it was undergoing maintenance (non-mission capable due to maintenance) at more than twice the target rate set by the JPO… This was primarily caused by a shortage of UK F-35 engineers. Over the same period, the UK F-35 fleet had aircraft unavailable to perform any missions because of a lack of spare parts (non-mission capable due to supply) at a rate which was over two-thirds higher than the JPO’s target rate.
In some cases, therefore, a number of our 38 in-service aircraft were effectively not in service.
Next steps: the first stage of recovery is accepting you have a problem
What the NAO’s report reveals is that we have too few aircraft, at too little availability, lacking some capabilities, with too few pilots and engineers, delivered late and far over budget. The F-35 is undoubtedly an extremely capable aircraft, significantly in advance of anything the RAF has previously operated, but as Gareth Davies, the Comptroller and Auditor General, who is head of the NAO, remarked with understatement, “The MoD now needs to decide where to prioritise its resources to improve capability in a way that maximises the full benefits of the F-35 programme to the UK”.
It is hard to know quite what to do at this stage. It is one thing to say that the delays, cost overruns and shortages are catastrophic and unacceptable—they are, and I do—but that does not get aircraft back into operational service. It is also regrettable but true that anyone familiar with MoD procurement over the past 20 or 30 years will find the NAO’s conclusions disappointing and disheartening, but not surprising. There have been egregious examples of mismanagement, such as the decision to switch to the fully carrier-capable F-35C then the reversal of that decision two years later.
The MoD has, as it often does, delayed certain parts of the programme in the hope of saving money, but actually ended up making it more expensive: it delayed construction of the Aircraft Signature Assessment Facility in 2021 and calculated it would save £82 million, while the NAO calculates it will have added an extra £16 million to the overall budget by the end of the decade. It has been secretive, evasive and mendacious about costs, but, even more worryingly, it seems to have deceived itself and accepted its own flimsy reassurances.
The Chair of the House of Commons Public Accounts Committee, Sir Geoffrey Clifton Brown, has fulminated about the findings of the NAO report, as is a tacit part of his job description.
There are serious shortcomings in the UK fleet today and slow progress has been
made towards the MoD’s commitment to acquiring 138 aircraft. The MoD must now remove barriers to increasing capability and take the necessary steps to ensure the F-35 programme delivers the value this country needs it to.
All of that is undoubtedly true. In terms of concrete action, however, it doesn’t really mean much: “remove barriers” and “take the necessary steps”. Those are actions any sensible person would take, but what are they, and how should the MoD go about it?
(The Public Accounts Committee will now conduct an inquiry into the issue.)
The Ministry of Defence’s response has been characteristic: to miss the point, underline the positive aspects of the report and refer windily to the government’s wider policies.
The National Audit Office’s report rightly recognises the world-class capabilities of the F-35 fighter jet, as well as its significant economic benefits—including £22 billion of work for UK companies, creating thousands of jobs. The programme continues to operate within its approved budget and the UK will have two full squadrons of F-35 fighter jets ready for deployment by the end of this year. We also recently announced we will purchase 12 F-35As, supporting 20,000 jobs in the UK, and join Nato’s dual capable aircraft nuclear mission.
Anyone who thinks that is an adequate response to the NAO’s criticisms should not be in a serious job, in the Ministry of Defence or anywhere else. There is no mention of personnel shortages, of huge delays, of gaps in capability or in delays to weapons systems. It fixates on one positive aspect, the F-35’s advanced nature, makes three references to the F-35 programme’s contribution to the economy and moves on to the future procurement of F-35As, saying nothing of the severe problems with the current F-35B fleet. It is to be hoped that the Defence Secretary, John Healey, will make a statement to the House of Commons next week, or, if he does not, that the Shadow Defence Secretary James Cartlidge tables an Urgent Question on the matter.
Essentially there are three questions the Ministry of Defence has to answer:
How many of the deficiencies identified by the NAO, such as shortage of pilots and engineers, maintenance requirements and lack of stand-off weapons, can be mitigated by spending more money?
Is the Ministry of Defence likely to receive more money to address these problems?
What can be done to speed up delivery of the rest of the F-35B fleet and bring forward the type’s full in-service date?
There are other, deeper questions for the future: why does this keep happening to defence procurement projects; why is no-one ever held accountable; what changes will be put in place to avoid these kinds of grotesque inflations of budgets and schedules; and what difference, and specifically how, will the new National Armaments Director make to the procurement system when he or she is appointed?
The NAO’s findings on the F-35 programme are cause for enormous concern in their own right: this is equipment which is likely to end up costing the taxpayer something like £70 billion over its lifetime (and no-one would be surprised if that figure rose substantially), and it is not currently fulfilling the capabilities for which it was designed and acquired. That in turn means the armed forces are unable to carry out tasks which the Ministry of Defence has said they can and will carry out.
But it is also symbolic, an avatar for the long-standing, thoroughgoing, vastly expensive catastrophe which is the MoD’s procurement régime. The Defence Secretary has talked a great deal about addressing this problem, partly through his Defence Reform project and the creation of a powerful National Armaments Directorate Group, underpinned by the forthcoming Defence Industrial Strategy. But cynics have heard this sort of promise before. The government will need to go a lot further to show that it has found a solution to endemic problems which have beset defence procurement for decades.