The first Sikorsky S-24 Type G-1 Il'ya Muromets four-engine bomber flew in December 1915. Four Sikorsky S-24 Type G-1s were completed in 1915-1916 with quad mountings various engines: 150hp Sunbeam, 125hp Argus, 140hp Argus, and 160hp Sunbeams respectively. 
|Sikorsky S-24 Type G-1|
|Designer||Igor I. Sikorsky|
|First flight||Dec 1915 |
|Number built||4 |
|Developed from||Sikorsky S-22|
For more information, see Wikipedia:Sikorsky Ilya Muromets.