I take it you're wanting it to look "depot" applied rather than local unit-painted using brushes & rollers, eh?
I wouldn't think it'd be an issue, although I'd get the pre-mixed tempera rather than the powdered tempera for airbrushing... One thing though, you'll have tto thin hell outta the stuff and add a wetting agent to it, like dish soap.. The stuffs dries way to fast for alcohol to be used as a thinner, I'd reckon... I'd also think you'll want as big a tip as you can screw on your airbrush... Aso, no matter how well you mix it, you're gonna have some clumps of paint in there, so get some paint strainers and run you mix through one into the paint-cup...