M.Dusing German Aviation Industry in WWI. Volume 1 (A Centennial Perspective on Great War Airplanes 84)

Hans-Grade-Werke, Bork i. Mark

Aircraft Development:

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  The competition was huge at the time. Grade felt this during many competitions and display flights in which he participated. The speeds that could be achieved with the “Schwalbe” (swallow) were no longer sufficient, so Grade decided to develop a racing monoplane. Two new models were developed. Type D was a single-seater with a 30 or 45 hp four-cylinder engine. For the first time, this type had a partially aluminum-clad fuselage made of tubular steel, in which the pilot was accommodated. However, the attainable maximum speed increased only to 110-115 Km/h.
  Although further types were also built at the Grade works in 1913 and 1914, the expected success failed to materialize, not least because of the collapse of civilian sport aviation. In particular, the measures taken under the National Flight Donation led to a steady decline in sales.
  After the outbreak of the World War, the capacities of Grade Flieger-Werke were used to repair front-line aircraft. Therefor an independent aeronautical development in Bork did not existed after the beginning of WWI. Grade’s influence within his company was so weakened by the directive rights of the military construction supervisors that he decided to sell his factory in 1916. The date of the establishment of the above company is January 1, 1917, the date of the takeover of Hans-Grade Flieger-Werke by Aviatik. The company manufactured about 550 Albatros B.II aircraft under license and repaired 250 Aviatik C I, C II and C III and DFW C V aircraft in 1917.