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 "Curtiss P-40 Warhawk"): The Curtiss P-40 Warhawk is an American single-engined, single-seat, all-metal fighter and ground-attack aircraft that first flew in 1938.
Relevant evidence: Yes