BOELCKE OSWALD: (1891-1916) German flying Ace of the World War One. Credited with 40 victories. Boelcke is widely considered the ''Father of the German combat air Pilots'', an influential figure also known as the ''Father of Air Fighting Tactics''. His innovative turn of mind codified his combat experiences into the first ever manual of fighter tactics distributed to an air force, the Dicta Boelcke. Boelcke was killed in an air crash collision. Rare and excellent signed 3.5 x 5.5 postcard photograph by Boelcke, the image showing the air fighter standing outdoors, in uniform, alongside Crown Prince Wilhelm (1882-1951) and two more Verdun decorated officers, Oberlieutenant von Brandis, the hero of Douaumont, and Kurt Rackow, the hero of the capture of Fort Vaux, all in uniform. The photograph bears the printed heading ''The army Commander in chief in Verdun, with three officers decorated with the ''Pour le Merite'' medal''. Signed in bold black ink `O. Boelcke´ across the image. VG