The UK Carrier Strike capability is nearing a critical milestone. Full Operating Capability (FOC) for the F-35B should be achieved during the forthcoming CSG25 deployment. Here we look at latest progress with the jet and the wider carrier strike capability development.

Lightning FOC

According to the annual Government Major Projects Portfolio report published in January 2025, FOC for F-35 was progressing but was rated ‘amber’, indicating risks in meeting the deadline. The specialised nature of the airframe, which combines complex stealth coatings, vertical lift hardware, and high-voltage electronic systems, places exceptional demands on maintainers. Efforts to boost retention and attract qualified personnel have been launched, but results will take time to materialise.

FOC for the F-35B is defined as the ability to deploy two squadrons simultaneously to separate global theatres. The two existing frontline squadrons, RAF-badged 617 and RN-badged 809 Naval Air Squadron must be fully trained, equipped, and certified to operate from either carrier or land base. An RAF statement published this week implies FOC will be achieved: “Operation Highmast is poised to be a landmark event, with plans to declare full operational capability for both the jets and the Carrier Strike Group within the year”.

The two front-line units are based at RAF Marham together with 207 Squadron operational conversion unit (OCU), while 17 Squadron conducts test and evaluation (TEU) work from Edwards AFB in California. Although with many caveats, the Lightning Force is maturing slowly. 617 Squadron is now commanded by a Royal Marine, Lt Col Mike Carty, the first RM to lead a fighter squadron in the UK. 809 Squadron which recommissioned in December 2023 is commanded by Cdr Mick Smith and will deploy, having declared Initial Operating Capability.

The F-35B’s integration with the Meteor beyond-visual-range air-to-air missile will mark a significant leap in the aircraft’s lethality. Flight tests carried out at NAS Pax River during November 2024 have confirmed the successful carriage and release parameters of Meteor from the F-35s internal weapons bay, paving the way for future full integration. Once fielded on F-35, this combination will offer unmatched reach and kill probability in contested airspace.

The Meteor integration process is closely tied to the F-35 Block 4 upgrade, which includes the Technology Refresh 3 (TR-3) hardware suite. This upgrade is necessary to support Meteor and the SPEAR-3 precision stand-off missile, but delays in the software to accompany the TR-3 development have impacted the overall timeline for these integrations. F-35 must fly without Meteor or SPEAR-3, probably until 2030,  a scandalous situation impacting the power and reach of the whole carrier programme but the MoD has little power to accelerate progress.

At present, the Lighting force has 35 jets and deliveries of the remaining jets that make up the first tranche of 48 are expected to conclude by the end of this year. In parallel, discussions are underway for a second batch of 27 aircraft, subject to the decisions of the now much-delayed SDR. If secured, this would bring the future fleet to 74 aircraft by the early 2030s. A third operational squadron is also planned, though its identity and formation timeline remain undisclosed.

809 NAS and RAF 617 Squadron engineers washing down a jet on HMS Prince of Wales’ aircraft lift, exercise Strike Warrior, October 2024.
Crowsnest debacle

As a cornerstone of Carrier Strike, the F-35B Lightning is expected to operate seamlessly with the QEC aircraft carriers and the CROWSNEST Airborne Surveillance and Control System (ASaC). Any delay in one element risks derailing the coordinated progress required across all three pillars of the capability.

It remains current MoD policy to withdraw the Merlin-based Crowsnest ASaC at the end of 2029 as has been the plan since 2015. The system has not yet even achieved FOC as a result of the disastrous design and procurement process that has been ongoing over a decade. The original price tag was £269M but by December 2023, £425.7 million had been spent with costs still rising. If and when FOC will be achieved remains uncertain, although the system will be deployed as an integral part of the CSG25 deployment, whatever its limitations. Details of the performance shortfalls are classified but are believed to be primarily software related. Integrating the new ASaC system with the existing Merlin Mk2 avionics has also been challenging.

To compound the colossal expense, its is planned the system will only serve for 5 years, although this will depend on a very rapid procurement of a UAS-based alternative which is supposed to be in service by 2030. To procure a novel solution, test, and integrate with the carriers before the end of 2029 appears highly optimistic. Either ASaC capability would be gapped, or more likely, it will be extended in service to allow time for the replacement to mature.

Dispensing with CROWSNEST will, at least, allow the modest fleet of 30 Merlin Mk2 helicopters to concentrate fully on their core ASW role. The Merlins are going be extended in service until 2040 and the airframes will also have to cycle through the factory at Yeovil for substantial refurbishment (possibly including new engines), which will reduce overall availability in the early-mid-2030s.

Demonstrating the intention to dispense with CROWSNEST as soon as possible, the MoD recently published a Request for Information (RFI) inviting industry input on potential replacements. Although not specified in the RFI, the solution is expected to be based on an uncrewed air vehicle. The replacement system is expected to meet the same requirement for persistent 24-hour surveillance with advanced detection capabilities against both surface and airborne threats, including anti-ship missiles. The major difference is that data collected by the sensors will have to be sent back to the carrier or shore station to maintain a human in the loop, even if more of the analysis is automated. Initial entry into service is anticipated between 2030 and 2035 in a project with a very broad cost envelope estimated between £0.5 and £1.5 billion.

The ideal solution would be a long-endurance fixed-wing UAS that could attain higher altitudes than rotary-wing platforms. Aircraft such as the General Atomics MQ1C Mojave or MQ-9B Maritime Protector Remotely Piloted Air System (RPAS) would probably be the optimum type of solution but vehicles of this size would require substantial modifications to the carriers to fit small-medium size catapults and arrestor gear. It is far from certain the RN will be properly funded to fulfil its ambitions for the carriers and a RWUAS platform such as the Leonardo Proteus might be more a more affordable option.

blankCROWSNEST – another fine procurement mess.

FOC for the wider Carrier Enabled Power Projection (CEPP) was due to be declared by March 2026, although official sources have gone very quiet on this. This will certify the ability to deploy a fully integrated Carrier Strike Group, composed of an embarked air wing of 24 F-35Bs, CROWSNEST, supporting warships and auxiliaries, and a command staff able to operate independently for extended periods. The lack of solid support ships, surface escorts and missing integration of Meteor missile and SPEAR-3 stand-off weapons on F-35 means that the original ambition for full CEPP cannot be met next year.

On a more positive note, carrier strike capability is slowly improving, the forthcoming deployment will see HMS Prince of Wales sail with by far the most powerful air group the RN has put to sea since the 1970s, outmatched only by US carriers (and the French carrier, depending on capability metrics).