Wellington 1941=43
 

I seem to remember posting the above a few years ago, but I have forgotten the replies I received.
Sometime between the above dates a Wellington circled near our house for five or six minutes at roughly 4000ft both piston engines running at a low speed.
In the tail turret position a jet engine was running quite slowly, of course at the time I had no idea what it was.
Are there any books or articles where this aircraft & its flights are mentioned. Our house at that time was in Dunstable, Bedfordshire.

Whittle W2/700 was mounted on a Wellington in the position you describe. See Flight December 27 1945, page 672 for a photo.
Work on a thrust spoiler/reverser was amongst the tasks done with that FTB in 1944.
I can't think why it would have appeared near Dunstable as it's not near the base of Power Jets/Rover/R-R.

One of the jet test-bed Wellingtons was based at Bruntingthorpe with Power Jets from September 1944, later moving to Bitteswell until it was withdrawn from use in 1948. The Wimpy you saw was probably one of these I suspect.

However, if the 1941-43 date range is correct, the only aircraft it could have been is one of three Wellingtons used by Rolls-Royce at Hucknall from September 1942 onwards.