Information on period pilot maps

[Igo kyu]

I remember old Ordnance Survey maps being paper backed with some sort of quite wide woven cloth, I don't know whether they were pre or post WW2. It should be possible to get hold of some I'd have thought, they seemed to be quite hard wearing. That was the point of the cloth, holding the shape when the paper fell apart at the fold lines (I think paper now has plastic in it or something, back then it was much less durable).