Sikorsky Ilya Muromets

Ilya Muromets
Role	Heavy bomber
National origin	Russian Empire
Manufacturer	Russo-Baltic Wagon Company
Designer	Igor Sikorsky
First flight	11 December 1913
Introduction	1913
Retired	1922
Primary user	Imperial Russian Air Service
Produced	1913 to 1917
Number built	85+
Developed from	Sikorsky Russky Vityaz

The Sikorsky Ilya Muromets (Russian: Сикорский Илья Муромец) (Sikorsky S-22, S-23, S-24, S-25, S-26 and S-27) are a class of Russian pre-World War I large four-engine commercial airliners and heavy military bombers used during World War I by the Russian Empire. The aircraft series was named after Ilya Muromets, a hero from Slavic mythology. The series was based on the Russky Vityaz or Le Grand, the world's first four-engined aircraft, designed by Igor Sikorsky. The Ilya Muromets 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. 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, with the 1916-17 origin Zeppelin-Staaken R.VI, the only example of any of the Imperial German Riesenflugzeug airframe designs to be produced in any quantity during World War I.

The Ilya Muromets (Sikorsky S-22) was designed and constructed by Igor Sikorsky at the Russo-Baltic Carriage Factory (RBVZ) in Riga in 1913. It was based on his earlier S-21 Russky Vityaz, which started out as the twin-engined Le Grand, then as the twin tandem-engined Bolshoi Baltisky before placing all four of the Baltisky's engines in a tractor configuration along the lower wing's leading edge to create the Russky Vityaz — which had played an important role in the development of Russian aviation and the multi-engine aircraft industries of the world.

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