NAO: RAF's Advanced Jet a 'Disappointing Return' on £11 Billion

**UK's £71 Billion F-35 Fighter Jet Programme Faces Delays and Shortfalls: NAO Report**

Britain's ambitious £71 billion programme to develop its most advanced warplane, the F-35 Lightning, is facing significant setbacks due to equipment shortages, a lack of trained pilots and engineers, and persistent delays, according to a new report from the National Audit Office (NAO).

The F-35B stealth jets, used by both the Royal Air Force and the Royal Navy, are described by the NAO as “significantly superior” to any previous UK aircraft. However, the report criticizes the Ministry of Defence (MoD) for failing to meet its original goals, stating that the return on the £11 billion invested so far has been disappointing.

Although the F-35 is a largely American-led initiative, the UK manufactures about 15% of each jet by value, generating an estimated £22 billion in contracts for British companies and creating thousands of jobs. Still, as of June 2025, the UK had only 37 F-35B jets in service out of a planned total of 138, with full operational capability not expected for several years.

The report highlights a troubling performance gap. In 2024, the jets' "mission capable rate"—their ability to perform at least one of seven designated missions—was only about half of the MoD’s target. Even more concerning, the "full mission capable rate," which reflects a jet’s readiness to carry out all assigned missions, was just a third of the expected figure. Due to national security concerns, specific figures were withheld

The NAO cited "major personnel shortages" and "serious gaps" in engineering roles, adding that the MoD has struggled to maintain aircraft availability. This has directly impacted pilot training, with flying hours falling below required levels.

Delays in the delivery of the first 48 aircraft, which were initially due by April 2026, were attributed to both financial constraints and global production issues. The MoD’s affordability-driven decisions and global delays in the F-35 programme were also cited as key reasons for missed targets.

Looking ahead, the UK has announced plans to procure 12 F-35A jets, which are capable of carrying nuclear weapons but are not suited for aircraft carrier operations. These will support NATO’s dual-capable aircraft nuclear mission and are expected to bolster the country's deterrence posture.

In response, a Ministry of Defence spokesperson stated:

> “The National Audit Office’s report rightly recognises the world-class capabilities of the F-35 fighter jet and its significant economic impact—supporting £22 billion worth of work for UK firms and around 20,000 jobs. The programme remains within budget, and we’re on track to have two full squadrons of F-35s ready for deployment by the end of the year.”

Despite the challenges, the MoD insists that the programme remains on course and continues to deliver strategic and economic benefits. However, the NAO’s findings raise serious concerns about the long-term sustainability and readiness of the UK’s F-35 force.