A CHINESE-owned company is making parts for the top secret F-35 fighters flown by the UK and the US, it has emerged.

Printed circuit board maker Exception PCB makes parts that "control many of the F-35's core capabilities" according to publicity material produced by the Ministry of Defence.

6 An RAF F-35 flying over the North Sea accompanied by one from the US Marine Corps Credit: Getty Images - Getty

The fighter's “engines, lighting, fuel and navigation systems” are among the systems controlled by the Gloucestershire-based company’s products.

Britain has committed to buying 138 from US defence giant Lockheed Martin and the first batch arrived in June 2018.

Concerns have been raised about the involvement of a Chinese firm in such a top secret project at a time when suspicions linger about the country’s companies, such as Huawei, being used for espionage.

Clark Ince, a director of Hallmark Electronics, told Sky News it is possible to embed technology such as a chip without a customer's knowledge into a circuit board that could affect the way it functions.

Asked if it was risky allowing a Chinese-owned company to make circuit boards for the F-35 he replied: "Yes I think so, personally I think so."

'BREATHTAKING'

Tory MP and army reservist Bob Seely, who co-authored a paper about concerns about China's Huawei and Britain's 5G mobile network, described the involvement of Exception PCB as “breath-taking”.

"It's not a question of: Is this bad? But it's a question of: How bad is it?" he said, adding that he plans to raise the matter with Defence Secretary Penny Mordaunt.

The US has raised fears about Huawei’s close relationship with the Chinese government and laws which compel it to cooperate with Beijing’s state intelligence agencies.

But last month Theresa May gave the green light for Huawei to build part of Britain’s 5G network subject to a final approval by government.

Exception PCB was bought by Shenzhen Fastprint, a China-based company which is listed on the Shenzhen StockExchange, in 2013.

The MoD said the company's products are universal and used across both the military and civil aviation sectors.

“Exception PCB produces bare circuit boards and as a result there are no risks associated with their product in the F-35 aircraft supply chain,” said a spokesman.

Exeception PCB have been approached for comment.

6 The £100m Lightning II stealth jets will be based at RAF Marham, Norfolk Credit: EPA

6 The 1,200mph fighter plane has the ability to land vertically when needed Credit: PA:Press Association

Meanwhile, it has emerged a leaked Pentagon report said the F-35 fighter jet can only fly at supersonic speeds for short bursts or it may start to "crack".

It's been claimed the £100million Lightning II stealth jets are at risk of structural damage when hitting their top speeds of around 1,200mph.

Defense News claims the problem may make it impossible for the F-35 to conduct supersonic intercepts when in combat adding there was a "risk of structural damage."

The reported deficiencies were first observed in late 2011 following tests where the F-35B and F-35C both flew at speeds of Mach 1.3 and Mach 1.4, it's claimed.

During one post-flight inspection in November 2011, it was discovered one jet had sustained “bubbling (and) blistering” of its stealth coating, according to the documents obtained by Defense News.

Vice Admiral Mat Winter, who leads the F-35 programme for the Pentagon, said his department has taken steps to tackle the problem .

6

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Last November it was announced Britain will double its fleet of F-35 stealth fighter jets by ordering 17 more from the States.

In October the MoD was forced to ground its new fighter jet fleet after a faulty fuel tube caused a crash in the US.

Around 250 aircraft were grounded in the US and about 100 worldwide after a US F-35B stealth jet went down over Beaufort, South Carolina, in September.

6 Tests have shown he combat aircraft may have weaknesses, claims a report Credit: PA:Press Association

6 Britain has committed to buying 138 from US defence giant Lockheed Martin Credit: PA:Press Association

Moment first of Britain's new £150m F-35 Lightning fighter jets takes off from US on way to RAF Marham

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