Gottinger Monograph N: German Research and Development on Rotating Wing Aircraft 1939-1945 (Library of Flight)

After World War II the British Ministry of Supply ordered the German aeronautical research establishments in Gottingen (AVA) and Braunschweig (DFL) to summarize research results obtained from 1939 to 1945. Gottinger Monograph N deals with all German helicopter and autogyro development during this period, including the contributions of Focke, Flettner, von Doblhoff, and others who brought rotorcraft into series production maturity.