It might interest all the responders to my original post to know something of the background to my query. I was passed some information from someone who was at Akrotiri around 1957 and thought that had seen evidence of a secret spy plane. He had been told to move away from a well-guarded part of the airfield, saw a wing shape that, years later he noticed on a B2 bomber, and heard an exhaust with a throbbing sound. He had read reports that the Aurora made a throbbing sound and now thought that he had witnessed an Aurora.
I have reported back to my correspondent that, in my view, 1957 was far too early for the hypothesised Aurora to have been flying in development, far less operationally; that the B2 wing shape is optimised for low-observable, subsonic rather than hypersonic flight; and that, if some sort of secret spy plane had been involved, it was more likely to have been a U2. I also tentatively explained the throbbing noise as possibly emanating from a Javelin, which I think were based in Cyprus at that time, as I had heard something like this while serving in the Far East.
Thank you to all those who replied to my query and confirmed that the noise I heard was indeed from a Javelin and made it likely that this was also the same sort of noise reported by my contact. I wonder if the "B2-like" wing shape that he had seen could have been on a Javelin viewed at an angle that superimposed the tail plane on the main wing and gave the appearance of a jagged rear edge.