Upon researching the crosshair symbol that Zodiac used as his signature I found the German Luftwaffe symbol which resembles the crosshair symbol.
Luftwaffe is a generic German term for an air force. It is also the official name for two of the four historic German air forces, the Wehrmacht air arm founded in 1935 and disbanded in 1946; and the current Bundeswehr air arm founded in 1956.
Coincidentally the suspect Henning Lagies was born in Germany in 1935 and in 1946 he claims to have seen 5 simultaneous whirlwinds touch down in a field of oats in the locations that create a stellar map of 5 pentegrams. Story at http://www.eclipse-chasers.com/SchindlersShow.php?name=CropCircleSky Henning also immigrated from Germany to Canada, just North of California in 1956. He had family living in San Diego during the Zodiac killings.