The McDonnell Douglas F-15 Eagle is widely regarded as the best fighter in the world, despite its large size and high operating cost. It was originally designed to counter the threat of the Soviet MiG-25 Foxbat, which was thought at the time to be a high-performance fighter capable of fantastic speeds and maneuverability. Thus the F-15 was designed for top performance in all aspects of aerial combat. With its vast wing area and pair of extremely powerful engines, the F-15 delivered the ultimate in dogfighting technology when it first few in 1972. It pioneered the HOTAS (hands on throttle and stick) concept to ease the pilot's task in combat. The Eagle also affords its pilot superb all-around view from the cockpit, carries the powerful Hughes APG-63 pulse-Doppler radar, and has a large missile-carrying capacity. It can accelerate while flying straight up! Replaced by later models in US Air Force units, the 'A' model now serves in the Air National Guard.