▁the ▁ground ▁attack ▁role , ▁can non ▁fire ▁may ▁be ▁emphas ized . ▁However , ▁modern ▁f ighter ▁aircraft ▁use ▁gy ro scop es ▁and ▁in ert ial ▁sens ors ▁couple d ▁with ▁rad ar ▁and ▁optical ▁computing ▁guns ights ▁that ▁make ▁the ▁use ▁of ▁trac ers ▁in ▁can non ▁am mun ition ▁unnecessary . ▁As ▁long ▁as ▁the ▁pilot ▁can ▁put ▁the ▁" pi pper " ▁( a im ing ▁point ) ▁in ▁the ▁head - up ▁display ▁( H UD ) ▁onto ▁the ▁target , ▁he ▁can ▁be ▁assured ▁that ▁the ▁burst ▁will ▁be ▁on ▁target , ▁since ▁the ▁computers ▁automatically ▁compute ▁range , ▁closing ▁rate , ▁def lection , ▁later al ▁acceler ations , ▁and ▁even ▁weather ▁conditions ▁to ▁calculate ▁target ▁lead ▁and ▁aim point . ▁Thus ▁one ▁of ▁the ▁primary ▁reasons ▁for ▁using ▁trac ers ▁on ▁aircraft ▁in ▁the ▁first ▁place , ▁uncertainty ▁over ▁where ▁the ▁bul lets ▁will ▁end ▁up ▁in ▁relation ▁to ▁the ▁target , ▁is ▁removed . ▁Another ▁use ▁for ▁the ▁trac er ▁is ▁in ▁tank ▁h ull ▁mach in eg uns , ▁of ▁mostly ▁out - dated ▁t anks , ▁where ▁the ▁mach in eg un ▁operator ▁cannot ▁sight ▁directly ▁along ▁the ▁bar rel , ▁thus ▁he ▁has ▁to ▁rely ▁on ▁trac er ▁bul lets ▁to ▁guide ▁his ▁aim . ▁Modern ▁main ▁battle ▁t anks ▁and ▁arm ored ▁fighting ▁vehicles , ▁however , ▁employ ▁advanced ▁fire ▁control ▁systems ▁that ▁can ▁accur ately ▁aim ▁secondary ▁weapons ▁along ▁with ▁the ▁main ▁arm ament ; ▁although ▁the ▁continued