Well if the articles I read on the way planes positions are handled, are correct, dodging tracers or listening for gun shots would be impossible. You're getting the info 1/4 to 1/2 second after what the guy saw on his end. So if you see tracers (or hear bullets) and dodge, the guy shooting would have already seen them hitting you - scoring a hit. Just as you couldn't be rammed, only ram (i.e, your front end shows you running into a plane,), you shouldn't be able to dodge a tracer. You're seeing something that happened 1/4 - 1/2 second earlier.