The Allies would have crushed Nazi Germany 'within three years' if the RAF had not rejected plans by a British inventor to build the world's first jet-powered fighter planes, according to new research.

Inventor Sir Frank Whittle was told his designs for a 500mph jet were 'totally unrealistic' and RAF chiefs refused to invest a penny in their development.

It meant the RAF engineer was forced to circulate his patent internationally in the hope of finding a private investor.

But the document fell into enemy hands and was used as the blueprint for Germany's own jet development programme....

Until now, it was widely believed that the race to design a jet-powered aircraft was fought independently between Whittle and German engineer Hans von Ohain.

But author John Golley, who researched the topic for more than 20 years, said von Ohain's efforts were made 'significantly easier' thanks to Whittle's patent.

'Whittle was allowed to file his patent without secrecy and within a few months it reached Berlin, where it was distributed to numerous aeronautical establishments,' Golley said....

'But Britain could have won the war by 1942 using the same technology, if the RAF had not rejected Whittle's designs at the outset.'...