I am not convinced that it's a corkscrew, I had a look at close the other day and it certainly looks like corkscrew type of layout but I don't think it actually is I think it's just over banked turns. I have some photos that are not allowed to post them yet. Will do as soon as I can
Okay, just had another look and there is certainly something in there which looks a little bit like a corkscrew but isn't.
If I don't get permission to post the photos in the next couple of days I will attempt to draw my own chart of what type of inversion it is, or even if it is an inversion.
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