horry1
I won't say I am an expert or experient modeler, but base on my experience; what you say, can be done.
I use a Paasche 'H' single action airbrush. I manage to paint a three tone color(stripes) camouflage on my 1/35 Tiger tank. It depends on what kind of pattern you want. For a German tank with two tone color or camo in large pattern(e.g. Jagdpatner), a single action airbrush should be OK. You can apply tapes or masking fluid on it.
But if you paint fine pattern camo, such as the 'stripes' on Tiger Tank or Sturmgeschutz, consider the following:
1) A fine nozzle on your single action airbrush. I use my Paasche H3HC3 color adjusting nozzle which can produce a 1/16" stripe.
2) Paint should be thinned in a correct ratio. I mix mine in a 3:1/ 4:1 ratio. You may have to do this right by trial and error.
3) Use a compressor. If you use a can propeller, your spray may get very messy and paint flow will be inconsistent when pressure in the can dies out.
Also, of course, it also takes practice.
I have not tried a double action airbrush before. Nevertheless, I believe double action should be better and can produce finer pattern.