J.Herris German Aircraft of Minor Manufacturers in WW1. Vol II (A Centennial Perspective on Great War Airplanes 50)

This machine was built by the Union-Flugzeugwerke GmbH in Berlin-Teltow (Germany), a really small prewar airplane factory which existed from 1912 to 1916. But there were some famous names in the history of the Union-Flugzeugwerke
   Dr Josef Sablatnig (1868-1945) set with a Pfeil-Doppeldecker (constructed and built by Ing Karl Bomhard) a new world record on September 27, 1912 with three passengers to a height of 1,120 metres. By the end of 1912, the two were joined by Georg Konig and formed the Union-Flugzeugwerke GmbH in Berlin-Teltow (Germany). Up to 1916 it designed aircraft, but lack of orders led to the take-over of the company by the Norddeutsche Flugzeugwerke. The aircraft all had a characteristic wing in the shape of an arrow. This design proved to be insufficient and was later abandoned. In 1915 he constructed his first seaplane and in 1916 he formed the Sablatnig-Flugzeugbau GmbH in Berlin.
   The unique Union Wasserdoppeldecker (biplane seaplane) was designed in 1913. The 3-bay floatplane was powered by a 120 hp Austro-Daimler engine. The machine was bought by the German Marine and got the designation 73 (if the German number painters were secure ). The machine crashed before the start of the war.
   The Union-Flugzeugwerke made a few own designed aeroplanes. Almost unknown is the Union G.I (yes a Grossflugzeug) of 1915 with four (!) engines (115 hp Daimler). Is quoted as one of the first German 4-engined planes. The machine was not accepted by Idflieg, so the designation G.I may be spurious. Have never seen a picture or drawing of the Union G.I. So there are still machines to finds out.

M.Dusing German Aviation Industry in WWI. Volume 2 (A Centennial Perspective on Great War Airplanes 85)

Union Flugzeugwerke, Berlin-Teltow (Mark)

  By the end of 1912 Karl Bomhard and Josef Sablatnig formed the Union-Flugzeugwerke GmbH in Berlin-Teltow. The two were joined by Georg Konig as aircraft designer. Up to 1916 the Union Flugzeugwerke designed and produced aircraft, but lack of orders led to the take-over of the company by the Norddeutsche Flugzeugwerke. The aircraft all had a characteristic wing in the shape of an arrow. This design proved to be insufficient and was later abandoned. In 1915 J. Sablatnig constructed his first seaplane and in 1916 he formed the Sablatnig-Flugzeugbau GmbH in Berlin.
  Josef Sablatnig studied mechanical and electrical engineering in Graz and Brno. In 1909 he trained as a pilot with the company Flugmaschine Wright GmbH in Johannisthal. Sablatnig, who may also be considered the world's first night pilot, set several high-altitude flight records at Johannisthal in September 1913. He then participated in the founding of "Union-Flugzeugwerke GmbH" in Teltow near Berlin, where he was involved in the design of new aircraft types as technical director.


Aircraft Development:

  The unique Union Wasserdoppeldecker (sea-biplane) was designed in 1913. The 3-bay floatplane was powered by a 120 hp Austro-Daimler engine. The machine was bought by the German Marine and got the navy number 73, but crashed before the beginning of the war. This machine was built by the Union-Flugzeugwerke GmbH in Berlin-Teltow (Germany), a really small prewar airplane factory which existed from 1912 to 1916.
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