Aerial photograph airfield symbols

[mimithem]

Hello friends,

recently I purchased some aerial photographs taken by italian a/c after the fall of Greece (May-October 1941) depicting three Greek airfields, formerly used by the RAF and the Hellenic RAF during the operations 1940-1941.

Looking at the photographs I found some very strange symbols shown as to be on the ground of the airfields.

The symbols are just as the following ones:







As you can see yourselves the first symbol is an angle, the second one looks like a comb, while the last is a cycle. The angles appear on every imaginable corner of airfield, while the combs seem to follow the fictious line which connects them to the angles, thus creating the imaginable limits of every airfield. The are just like in the following image:



They seem to be somehow on the ground of the airfield. They did not exist during the days of operations. Could the Italians have put them on the ground itself?

Any idea of what they are and their role? Are they painted signs? They are all the same on all three airfields...