Stinger IGLA useless against small bird and warthog

[loneangels2016]

Is there a trick to downing a small bird or a fantan or warthog woth stinger or igla? It never works, the airborne machine always dodges it. What should i use to bring these things down? 

[sosp]

This is what i do, i place down AA and stay close to it and i keep aiming to the (Viper/Bird) until she come to me after that i let the AA hit it down then i shoot it with my stinger, this is what all bf4 players doing now.

And you can't take down a jet with stingers because it will probably go of range and the missile will keep going forward.