Britain’s F-35: seven roles, not all within reach

The Minister of State for Defence Readiness and Industry, Luke Pollard, has set out the seven core combat missions that the United Kingdom builds its fleet of F-35 stealth fighters around, doing so in a written parliamentary answer published on 12 June in response to the Conservative MP Ben Obese-Jecty, who has questioned ministers about the programme on a number of previous occasions.

The list is drawn from NATO’s air power doctrine and it covers the full range of jobs that a modern fighter is expected to perform, which the minister grouped under seven headings: attacking enemy aircraft and airfields, known as offensive counter-air; defending friendly airspace, or defensive counter-air; knocking out enemy radar and missile systems, referred to as the suppression and destruction of enemy air defences; striking targets behind the front line, which is called air interdiction; supporting troops on the ground, known as close air support; gathering intelligence and conducting electronic warfare; and carrying out attacks on the most strategically important targets, described as strategic attack.

The fleet in question is known as the Lightning Force, it is operated jointly by the Royal Air Force and the Royal Navy from RAF Marham in Norfolk, and it sits at the heart of Britain’s ability to project air power both from land bases and from the deck of the Royal Navy’s aircraft carriers.

What the minister’s answer describes is the doctrine that the force is designed around rather than a statement of what the jets can do at this precise moment, and it is in that gap between intention and current capability that the more revealing picture begins to emerge.

The F-35 is widely regarded as one of the most capable combat aircraft in the world, and the bodies that have scrutinised the British programme most critically have been careful to acknowledge as much. The National Audit Office, which is the government’s spending watchdog, described the jet in its July 2025 report as a technologically cutting-edge multi-role stealth fighter, while the Public Accounts Committee, in a follow-up assessment published at the end of October 2025, praised the programme’s technological achievements before turning to a series of shortfalls.

The point that runs through almost all of those shortfalls is that they concern the weapons and software the aircraft can carry rather than any failing of the airframe itself, and a great deal of that integration work is controlled not by Britain but by the United States-led office that runs the global F-35 programme.

Defending and attacking in the air

When it comes to the two air-to-air roles, both offensive and defensive counter-air, the British F-35s can already engage enemy aircraft using the missiles that are currently in service, namely the medium-range AMRAAM and the short-range ASRAAM, and they can strike airfields and other surface targets with the Paveway IV guided bomb.

The capability that is supposed to transform this part of the fleet’s performance is the European-built Meteor missile, which is designed to destroy enemy aircraft at far greater distances than the weapons the jets carry today, but its integration has been pushed back repeatedly and is no longer expected to be complete until the early 2030s, a delay that the National Audit Office attributed to poor performance by suppliers, to commercial arrangements that failed to prioritise delivery, and to the low priority given to the missile within the wider international programme.

The biggest gap: striking from a distance

The clearest limitation lies in the role of striking ground targets behind enemy lines, and in much of what counts as conventional strategic attack, because the National Audit Office found that the F-35 currently lacks what is known as a stand-off weapon, meaning a missile that can be fired from a safe distance so that the jet does not have to fly close to heavily defended targets.

The watchdog noted that the Paveway IV bomb the aircraft relies on does not have the range to do that job effectively, which leaves crews having to approach the very air defences that a stealth jet is meant to avoid, and the British answer to the problem, a cruise missile called SPEAR 3 that is made by the European manufacturer MBDA, has itself slipped into the early 2030s.

A separate decision taken some years ago not to fit the Storm Shadow missile to the type means that no other long-range strike weapon is currently planned for it, and to bridge the gap in the meantime the Ministry of Defence confirmed in May 2026 that it would buy an American precision-guided weapon, the Small Diameter Bomb II, which is also known as StormBreaker, through a government-to-government sale as a temporary stand-off capability.

No dedicated weapon to take out air defences

Suppressing or destroying an enemy’s radar and surface-to-air missile systems is, in theory, a task that suits a stealthy aircraft packed with sensors, and the F-35 can contribute to it by surviving in dangerous airspace and by finding and identifying targets for others to attack, yet the British fleet does not yet carry a dedicated weapon designed to do that job itself.

The obvious candidate, an American anti-radar missile known as the AGM-88G AARGM-ER, is among the munitions waiting on the delayed software upgrade, which means that a fully credible capability to knock out enemy defences from the air remains some way off for the moment.

Where the jet is already strong

There are two roles in which the British F-35 is already on much firmer ground, and the first of those is close air support, the task of backing up troops on the ground, for which the Paveway IV bomb is well suited and where the aircraft’s ability to fuse together information from its many sensors makes it an excellent platform for finding and striking targets in support of forces below it.

Reconnaissance is a genuine strength for the same reason, because gathering and sharing a detailed picture of the battlefield is one of the things the F-35 was built to do best, although the position on electronic warfare is rather more mixed, since the aircraft carries a capable built-in jamming and self-protection system while the dedicated electronic warfare missile that was meant to enhance it sits within the same delayed family of weapons, and a United States testing review reported that the major software effort underpinning these systems made no progress in adding new combat capability during 2025.

The nuclear question, and a different jet

The seventh and final role, strategic attack, is the one that most clearly goes beyond what the current fleet can do, because in its nuclear dimension it is simply not possible for the F-35B, which is the short take-off and vertical landing version of the jet that Britain currently flies, to carry nuclear weapons at all.

That limitation is the reason behind the government’s decision, which was announced in June 2025, to buy a dozen examples of a different variant, the conventional take-off F-35A, in order to restore Britain’s contribution to NATO’s nuclear-sharing arrangements by carrying the American B61-12 bomb.

A shared problem, and a fair assessment

The thread that connects nearly all of these gaps is the major software upgrade known as Block 4, which is led by the United States and which acts as the gateway through which almost every new weapon must pass before it can be cleared for use, and Britain finds itself fairly low down a long queue for that work, a frustration that it shares to varying degrees with the other countries that operate the aircraft.

On the wider question of readiness the picture is best described as mixed rather than alarming, because the Ministry of Defence aimed to declare what it calls Full Operating Capability by the end of 2025, which is roughly two years later than was first planned, and the National Audit Office noted that it intended to do so even with significant gaps still unresolved, including the missing stand-off weapon, the absence of a sovereign facility to check that the jets retain their stealth qualities, and a shortage of personnel, while it also warned that the milestone would not be sustainable in the short term.

Aircraft availability did improve during the major carrier deployment of 2025 aboard HMS Prince of Wales, when the fleet broadly met its targets for the proportion of jets ready to fly, although the watchdog cautioned that those rates were unlikely to hold once the deployment came to an end, and the same reports drew attention to a forecast shortage of pilots that lasts until around 2029 or 2030, to a recruitment drive for 168 additional engineers, and to corrosion problems that emerged after long periods of operating at sea on the deployment that was known as Operation Highmast. The National Audit Office also put the likely lifetime cost of the programme at close to £71 billion, which is considerably higher than the figure the Ministry of Defence had previously set out.

None of this should be allowed to obscure the broader conclusion, which is that the seven mission sets the minister listed represent the intended design of a mature F-35 force rather than a checklist that the aircraft has somehow failed, and the type has in any case already been used in combat by both Britain and its allies. As things stand today the Lightning Force can credibly carry out close air support, reconnaissance and the fundamentals of air-to-air combat, while it has openly acknowledged, and very largely funded, the work that is needed to close its remaining shortfalls in long-range strike, in the suppression of enemy air defences, in full electronic warfare and in the nuclear strand of strategic attack.

The fairest way to read the minister’s answer, in other words, is not that the doctrine amounts to wishful thinking, but rather that the fleet remains several years, and one badly delayed software upgrade, away from being able to fly all seven of those missions to their full potential.