Question: The Sikorsky S-1 was the first fixed wing aircraft design by Igor Ivanovich Sikorsky, a Russian-American aviation pioneer in both helicopters and fixed-wing aircraft, first success came with which aircraft?
Sentence (from "Igor Sikorsky"): and in the fall of that year the aircraft won for its young designer, builder and pilot first prize in the military competition at Petrograd.
Relevant evidence: No