Why not instead of making a hollow fusalage to drop weapons, create a new piece that gives the same illusion. It would look something like the retractable landing gear but larger and just the doors with no landing gear. When you go to the settings for this new piece, it will give you a limited inventory that changes size according to how large the fusalage is. Then you can select what weapons you want to be stored inside this piece. The weapons aren't actually inside the plane. When you fire a certain weapon, the piece will spawn the weapon in a way that makes it look as if it came out of the plane. That way players on less powerful devices can achieve the same effect as those more realistic mechanisms made in-game.