The Sikorsky Ilya Muromets were a class of Russian pre-World War I large four-engine commercial airliners and military heavy bombers used during World War I by the Russian Empire.The aircraft series was named after Ilya Muromet, a hero from Slavic mythology The series was based on the Russky Vityaz or Le Grand, the world's first four-engine aircraft, designed by Igor Sikorsky. The Ilya Muromet aircraft as it appeared in 1913 was a revolutionary design, intended for commercial service with its spacious fuselage incorporating a passenger saloon and washroom on board. The Ilya Muromets is the world's first multi-engine aircraft in production and at least sixty were built. During World War I, it became the first four-engine bomber to equip a dedicated strategic bombing unit. This heavy bomber was unrivaled in the early stages of the war, as the Central Powers had no aircraft capable enough to rival it until much later.
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