Ilya Muromets
The first aircraft to ever have incorporated a tail gunner position was the Sikorsky "Ilya Muromets" bomber, which became active during the First World War and the last years of the Russian Empire. The "Ilya Muromets" prototype flew for the first time in 1913, with no guns on board and no rear position for the crew. When the war broke out, in 1914, only a few "Ilya Muromets" aircraft had been built, but increasing numbers were required because of the war effort. After having entered the mass-production phase and having seen combat all along the first year of war against the fighter planes of the German Empire, a rear-defending position appeared to the Imperial Russian Air Service to be increasingly vital to protect both the plane and its crewmen. Such an arrangement, during March 1916, saw light of day on the model S-25 (variant Geh-2) of the Sikorsky "Ilya Muromets" bomber plane. This aircraft was the first in history to include on its ending tail area a gunner position. Mass-production of "Ilya Muromets" bomber commenced, with the final example being completed in 1918, by which time in excess of 80 aircraft had been reportedly completed. Those "Ilya Muromets" that served after the Russian Revolution were inducted into the Soviet Air Forces.