Northrop YA-9A
In 1972, the Air Force conducted a fly-off competition between Northrop’s YA-9A and Fairchild Republic’s YA-10A prototypes. The winner would become the service’s new close air support platform, replacing the aging propeller-driven A-1 Skyraider. While the YA-9 had several advantages over its competitor, the A-10’s engines offered greater survivability and the double tail did a better job of hiding the engine exhaust’s infrared signature.
