The Lockheed YF-22 is a prototype stealth fighter aircraft developed by Lockheed Martin for the United States Air Force. It was designed to demonstrate advanced technologies for air superiority and features a unique shape that reduces radar visibility. The YF-22 is part of the Advanced Tactical Fighter program and was intended to replace the aging fleet of F-15 and F-16 fighters. First flown in 1990, the YF-22 showcased its capabilities through various flight tests, leading to its selection as the basis for the operational F-22 Raptor. The aircraft is known for its high speed, agility, and advanced avionics, making it a significant advancement in military aviation technology.