It’s a Moynet Jupiter. Flown in December 1963 with all sorts of hopes for series production, but in the end only two were built.

http://en.wikipedia.org/wiki/File:Moynet_Jupiter_F-BLKY_TNF_040671-1-.jpg

It’s all hedged with phrases like ‘suggests that’ and ‘could have’ and ‘it’s possible that’. Mr Decre may be a serious researcher in the archives, but ultimately he’s using the familiar device of setting up a scenario and then inviting people to prove him wrong.
It’s usually virtually impossible to prove a negative (which is why an accused in court is innocent until proved guilty in all properly-run countries), and the end result is often that fairly outrageous claims become at least partly-accepted. Where I am in Liverpool, you’ve only got to look at the assertions that Hitler visited the city or that Jack the Ripper was a Liverpool businessman to get the general idea. And dare I mention Douglas Bader at the Stork Hotel?

X-configuration? Just don’t mention the Vulture:diablo:
It’s a bit unfair to say the Eagle would have beaten the Merlin to death. It was a 3,500hp engine of the late war period, a different beast completely – think of a Sabre on steroids – and was never fully debugged before Rolls Royce gave up to concentrate on turbines. With hindsight, a creature out of its time from the very beginning.

I have seen the trailer on YouTube, and it did cross my mind that perhaps it was an over the top sales pitch for a book that could be quite an illuminating read.
On the other hand, looking at the author’s own website http://www.rupertmatthews.com, although he has written other aviation stuff, he is nothing if not versatile. His list of published titles is formidably long, covering everything from true-life (his words!) stories of aliens and UFOs to dictionaries of dinosaurs and anthologies of bomber command heroes. At a very quick guess from his site I’d reckon he’s written about 300 books.
Good luck to him and anyone else toiling away as a writer, but I doubt if he’s done much original research on the He100/He113 (delete as appropriate).

Anyone remember Cone of Silence, from 1960, with the Avro Ashton WB493 doubling up as the Atlas Phoenix?

Much the same idea was around a few years later with Bristol’s Coupled Proteus. That too was hardly a great success.
http://www.flightglobal.com/pdfarchive/view/1951/1951%20-%200153.html

Surprised nobody’s mentioned the Boscombe Down Mi-8s yet.

I remember Liverpool’s first Caravelle using one in November 1964. Liverpool’s first jet, actually.