I find that on some aircraft builds I need to airbrush all sides in one sitting. Usually there is a place on the aircraft I can insert a rod or clamp or something to securely handle the model during painting without touching the actual model.
On some builds I an unable to find a good way to create a temporary handle. For these I place the entire model into a clamp. Using a clamp with rubber ends I can secure the model with just enough pressure that the model will hold with friction.
I have clamped it end to end or wing tip to wing tip, whichever works and secures the model for handling. As I airbrush I gingerly move or tip the clamped model around to get to all sides. I have even placed it on a lazy Susan.
Hope this helps next time you run into this.