11 July 2025, 02:30
An F-35 Lightning stealth jet performing a flypast during the commissioning ceremony for 809 Naval Air Squadron at RAF Marham in King’s Lynn in Norfolk.
Picture:
PA
Britain’s £71 billion programme to deliver its most advanced fighter jet has been hit by significant delays, equipment shortages, and staffing gaps, according to a new report from the National Audit Office (NAO).
The F-35 Lightning stealth aircraft – used by the Royal Air Force and launched from the Royal Navy’s aircraft carriers – is described by the NAO as “significantly superior” to any previous UK jet.
However, the government spending watchdog warns that the current capability falls short of expectations laid out in the Ministry of Defence’s (MoD) 2013 plans.
So far, around £11 billion has been spent on the programme, but the NAO says the return on that investment is “disappointing” compared to MoD’s original objective.
The NAO said: “In our view, the capability achieved for the estimated £11 billion spent to date is a disappointing return so far compared with MoD plans, even if other programme benefits have been significant”.
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A Lockheed Martin F-35 Lightning II fighter jet during a demonstration at Paris Air Show 2025.
Picture:
Getty
Although the F-35 is primarily a US-led project, around 15% of each aircraft is manufactured in the UK, generating £22 billion in contracts for British firms and supporting thousands of jobs.
Despite this economic boost, the report says the programme is underperforming operationally.
As of June 2025, the UK had 37 F-35B jets in service out of an eventual planned total of 138, with the jets expected to remain in service until 2069 at a £71 billion whole-life cost, according to NAO estimates.
.But in 2024, the NAO said the “mission capable rate” – the ability of an aircraft to perform at least one of its seven possible required missions – was approximately half the MoD’s target.
The “full mission capable rate” – an aircraft’s ability to carry out all its required missions – was only around a third of the target.
The MoD has not been able to sustainably deliver its targets for aircraft availability, resulting in flying hours below the requirement for pilots.“The MoD’s short-term affordability decisions and serious global programme delays have hindered the delivery of aircraft and other supporting capability”, the report said.
There are “major personnel shortages” across the F-35 force and “serious gaps” in engineering roles.
The report said delivery of the first phase of 48 aircraft, due by the end of April 2026, was behind schedule partly for financial reasons and partly because of global programme delays.
The UK operates the F-35B variant of the jet which can fly from the two Royal Navy aircraft carriers, but it has set out plans to order 12 F-35As which can carry nuclear weapons but cannot operate from the warships.
An MoD spokesman said: “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.”