I hope i do not drift to far off course of this thread, but I hope somebody can point me in the right direction?
Photo below is from a book of 1931 "In de schroefwind" of KLM pilot A. Viruly.
It is a photo of two gasholders in Leeuwarden (now the Bleekhof in Leeuwarden)
The arrows point roughly North while the Leeuwarden air base is approximately 4 km in NW direction.
Did they have already have a flight pattern in place?
