This is most often caused by the heli leaving the map. The way Rust works is that when the heli "leaves" the map the game just destroys it. At least as far as the game knows. So this fools our damage plugin into showing that the heli was destroyed and listing out the top damage dealers. Just for reference the heli hull has 10k health. So if you see that you were the top damage dealer and you only did a few thousand damage or less, most likely the heli just left the map.