Both of the A-X prototypes, the YA-10 and the Northrop YA-9, were designed to incorporate the weapon, although it was not available during the initial competition; the M61 Vulcan was used as a temporary replacement.
Oba prototypy AX, YA-10 a Northrop YA-9 boli navrhnuté tak, aby mohli použiť zbraň, hoci v priebehu prvej súťaže nebolo použitie možné, a ako dočasná náhrada bol používaný kanón M61 Vulcan.