Let me give you an example -
drop ["cl_fire", "", "Billboard", 1, 1, [0,0,0], [0,-3,1], 0, 1, 1, 0.001, [1,5], [1,1,1,1],[1,1,1,0],
, 0.1, 0.2, "", "",
_heli]
Let's say the above is what I'm using. You know that _heli makes, say, the Z/up and down velocity relative to the vehicle, so if the particle is set to move upwards, the particle will fall downwards. Now, in my case, this would make the dust particles appear in positions that are relative to the vehicle... do you understand now?