Mary Beth, since noone wants to tell you a gun run is when the gunships, that's the C model Huey's cover the H models, the troop carriers. Gun runs are usually carried out by two C models flying along the route the H models are taking and laying down suppressive fire with rockets and mini-guns. Just as one ship finishes the run the other is beginning so there is constant coverage. Gun runs can also be used to punish those who fail to attend unit reunions! Your brother Tom