Question: When was the American single-engined, single-seat, all-metal fighter and ground-attack aircraft first flew in which design Donovan Reese Berlin was associated?
Sentence (from "Polikarpov I-5"): The Polikarpov I-5 was a single-seat biplane which became the primary Soviet fighter between its introduction in 1931 through 1936, after which it became the standard advanced trainer.
Relevant evidence: No