Will it work or will it just bead up into little droplets on the surface? I've only ever airbrushed fondant but have a couple that want a buttercream cake. Do I need to use a crusting buttercream for successful airbrushing? Anyone have any tips for airbrushing on meringue buttercreams?

Yes, you can airbrush IMBC/SMBC. It shouldn't be any different than airbrushing any other BC.

i'd like to know too .
i read somewhere that since the meringue buttercreams do not crust, the airbrushing will not dry and it has had me wondering since then.
diane