The primary objective of the M.52 was to explore the transonic, the flights gradually building up to the supersonic. The rather awkward, un-faired shape of the 'plane was dictated by Whittle's design of the augmenter, whose exhaust was untapered throughout its length. The best description of the M.52 project is by Prof Brian Brinkworth (The Aeronautical Journal March 2010, No 1153).
The M.52 was a more ambitious project than the X1: a fact that some American historians find hard to recognise. It was the product of a much smaller team, working in complete secrecy in the middle of a war and it was much more circumscribed than the latter by the need to fit a design to an engine rather than the other way round. The USA also had the advantage of starting their design process early in 1945, when the use of turbojets was becoming commonplace and they had the benefit of discussions with Miles' team on some of the problems they would have to resolve.