A model from 5 years ago
Here is another Arup flying wing, this time the earlier -and smaller- S-2.
There were at least three different configurations and color schemes; here I am reproducing the one without the wheel fairings.
I have a great opinion of Bill Hannan and collaborators, my main source of info came via one article on Skyways magazine of January 1997, but I differ on the interpretation of the colors, and tend to believe, in spite of their explanations, that there were possibly three colors involved, red, black and aluminum. Just a personal interpretation, not more valid by any extent than theirs.