Thanks for the links to the historical Nat Geo maps. I looked at the 1915 and 1918 examples. Since the scale of those maps covers all of europe and down in to Africa, it's hard to imagine a pilot using these in particular. Maybe they had more localized maps of the same quality. If the printing of this map is typical then the maps were predominantly black and white with some colored shading along the borders. I'm guessing that the recon photos were also not used by the pilots since their purpose wasn't predominantly straffing or bombing.
If I was going from this limited information I would take a map of similar appearance to the Nat Geo images from 1915/18 and scale it down to 1:32 for placement in the cockpit. The RE8 I'm working on from WNW has a decal that is supposed to represent a map. It's obviously so small you can't make out any detail but the impression it gives me is more of a Google Earth satellite type image map rather than one like the Nat Geo prints (which seem more likely).
All this may seem kind of foolish since it is such a minor detail, but it is these kinds of little details that add interest and wonder imo. Thinking of a pilot in an open cockpit trying to figure out if the bend in the road below him matches the foldout map he is trying to hang onto so it doesn't blow away is a wonder.
