<hi style=afpcap>The Lockheed F-22 is the Air Force's choice as its ATF (Advanced Tactical Fighter) and replacement for the F-15 Eagle. The F-22 meets a requirement for long-range cruise at supersonic speeds without afterburning and makes use of low-observables (LO), or stealth, to defeat advanced radar defense systems. The F-22 also uses thrust vectoring to maneuver at high angles of attack (AOA) in air-to-air combat. Two-dimensional engine nozzles can be vectored 20 per cent up or down at any power setting. Coupled with large leading-edge wing flaps and overall low wing loading, the nozzles permit maneuver at low speeds and high flight angles.</hi>