Although Russia was not as industrially advanced as the other European powers, it would enter the First World War with the world’s first four-engine aircraft, the Sikorsky Ilya Muromets. After achieving success with a number of smaller aircraft, Igor Sikorsky joined the Russo-Baltic Railroad Car Factory (Russko-Baltiisky Vagonny Zaved or R-BVZ) in the spring of 1912 and began designing a massive aircraft, the Bol’shoi Bal’tisky (the Great Baltic), which had a wingspan of 88 ft and a length of 65 ft. Sikorsky had originally intended to use just two 100 hp Argus inline engines. Although he managed to take off on 2 March 1913, the Great Baltic proved to be underpowered. Undeterred, Sikorsky added two additional motors, which were installed in tandem with the first two, thereby providing both a tractor and pusher configuration. Beginning in May 1913, Sikorsky made several test flights in the Great Baltic, after which he reconfigured all of the engines to be on the leading edge of the lower wing for a tractor design. This proved far more successful, as indicated by a 2 August 1913 flight in which he carried eight people aloft for more than 2 hours.
Sikorsky’s next version, which served as the prototype of the wartime versions, was introduced in December 1913. It was similar to the Great Baltic, but it had a much larger fuselage that could accommodate up to sixteen passengers. By the spring of 1914, Sikorsky had developed the S-22B, dubbed the “Ilya Muromets” after a famous medieval Russian nobleman, it successfully completed a 1,600-mile round-trip flight between St. Petersburg and Kiev in June 1914. With the outbreak of the war, the S-22B and a sister aircraft were mobilized for service. An additional five were constructed by December 1914 and organized as the Eskadra Vozdushnykh Korablei (EVK) or Squadron of Flying Ships.
Because the first Ilya Muromets types had been designed primarily to carry passengers, once the war began Sikorsky started work on a slightly smaller version, the V-type, that could be used as a bomber. Introduced in spring 1915, the V-type Ilya Muromets had a wingspan of 97 ft 9 in. and a length of 57 ft 5 in. Because of Russia’s chronic shortage of engines, the R-BVZ was forced to rely upon a variety of engines for the V-type, including at least one that used different sets of engines; two 140 hp Argus and two 125 hp Argus inline engines. Of the thirty-two V-types produced, twenty-two were powered by four 150 hp Sunbeam inline motors, which provided a maximum speed of 68 mph. They had a loaded weight of 10,140 lbs, including a bomb load of approximately 1,100 lbs. Its crew of five to seven members were protected by free-firing machine guns. Three later versions were introduced during the war: the G-type and D-type introduced in 1916, and the E-type introduced in 1917. Of these, the E-type was the largest with a wingspan of 102 ft, a length of 61 ft 8 in., and a loaded weight of 15,500 lbs. Its four 220 hp Renault inline engines could produce a maximum speed of 80 mph. The E-type carried an eight-man crew, including two pilots, five gunners, and one mechanic. At least eight were constructed during 1917. The E-type went on to serve in the Red Air Force until 1924. The Sikorsky Ilya Muromets were sturdy, rugged aircraft. Of the approximate eighty that were built, only one was shot down by the enemy.
Voisin Type 3
In addition to the Ilya Muromets, Russia used a number of British and French light bombers that were either imported or were licensed-built by Russian manufacturers. The most numerous was the Voisin Type 3, of which Russia purchased 800 from France and produced approximately 400 license-built versions. This included a total of ninety-eight produced by the Lebedev factory in the last 2 years of the war. A few remained in service with the Red Air Force as late as 1923.