Sikorsky S-12

The S-12 was built at the suggestion of George Yankovsky as a lighter, single-seat version of the S-11 with an 80hp Gnome. He looped it in September 1913, the first time a Russian aircraft had performed this manoeuvre, and set a Russian height record of 3680m shortly afterwards. Most of the dozen or so S-11s that were built survived the war, and served in the earliest Soviet Air Force units during the Revolution. Several were still operational in 1922, mostly with an 80hp Le Rhone engine.