▁ 7 . 6 2   mm ▁min ig uns ▁could ▁select ively ▁fire ▁either ▁ 5 0 ▁or ▁ 1 0 0 ▁r ounds ▁per ▁second . ▁Cru ising ▁in ▁an ▁overhead ▁left - hand ▁orbit ▁at ▁ 1 2 0 ▁kn ots ▁air ▁speed ▁at ▁an ▁alt itude ▁of ▁, ▁the ▁gun ship ▁could ▁put ▁a ▁bullet ▁or ▁g low ing ▁red ▁trac er ▁( every ▁fifth ▁round ) ▁into ▁every ▁square ▁yard ▁of ▁a ▁football ▁field - s ized ▁target ▁in ▁potentially ▁less ▁than ▁ 1 0 ▁seconds . ▁And , ▁as ▁long ▁as ▁its ▁ 4 5 - f lare ▁and ▁ 2 4 , 0 0 0 - round ▁basic ▁load ▁of ▁am mun ition ▁held ▁out , ▁it ▁could ▁do ▁this ▁inter mitt ently ▁while ▁lo iter ing ▁over ▁the ▁target ▁for ▁hours . ▁ ▁The ▁less er ▁known ▁Fair child ▁AC - 1 1 9 G ▁Sh adow ▁were ▁tw in - engine ▁p ist on - power ed ▁gun ships ▁developed ▁by ▁the ▁United ▁States ▁during ▁the ▁Vietnam ▁War . ▁Ar med ▁with ▁four ▁ 7 . 6 2   mm ▁G AU - 2 / A ▁Min ig uns ▁and ▁two ▁ 2 0   mm ▁( 0 . 7 8 7   in ) ▁M 6 1 ▁V ul can ▁six - bar rel ▁rot ary ▁can n ons , ▁they ▁replaced ▁the ▁Douglas ▁AC - 4 7 ▁Spo ok y ▁and ▁operated ▁alongside ▁the ▁early ▁versions ▁of ▁the ▁AC - 1 3