The Sikorsky S-12 was a monoplane first flown in 1913. At least twelve were built, serving in both the Great War and the Russian Civil War. 
|Designer||Igor I. Sikorsky|
|Number built||≥ 12 |
|Engine||80hp Gnome rotary|
For more information, see Wikipedia:Sikorsky S-12.
- Durkota, p.302.