Question: The Advanced Tactical Fighter (ATF) was a demonstration and validation program undertaken by the United States Air Force, including the Soviet Sukhoi Su-27, a twin-engine supermaneuverable fighter aircraft designed by Sukhoi, it was designed to complement which aircraft?
Sentence (from "Advanced Tactical Fighter"): These aircraft were evaluated in 1991 and the Lockheed YF-22 was selected and later developed into the F-22 Raptor.
Relevant evidence: No