title_body: Do I need CW or CCW props for my plane? So I'm making an airplane with a motor at the front, do I use CW or CCW props?
  Pretty sure this is what counts as a puller plane (is that the right term?).
upvoted_answer: The decision between CW (clockwise) and CCW (counterclockwise) propellers has to do with the direction your motor/engine will spin, not really in regard to where you're putting the engine on the plane. CW props will create thrust behind them when spun in a clockwise direction, and CCW props will create thrust behind them when spun in a counterclockwise direction. It's that simple. :)
  For an electric motor driven plane, it probably doesn't matter which kind you get because it's highly likely that you can reverse the motor direction in the ESC (electric speed controller), but I'm not aware of any ability to do this with model plane gas engines. If you're using a gas engine, inquire to figure out either what kind of propeller the specs say to use (if this is listed) or what direction the engine spins and get the appropriate CW/CCW propellers.
  If the model airplane plans/kit you have calls for a specific kind of propeller, like for example if the plane was designed to fly better with one propeller rotation direction, I'd recommend abiding by their recommendations. There are quite interesting aerodynamic and physical phenomena like P-factor which the designer may have taken into account in the aircraft layout, resulting in the design requiring a specific kind of propeller.