Just about daily I receive emails about people building single motor jets and have installed a Grayson ParkJet motor and ask “Do I need a pusher prop?” The answer NO. Reverse Props also called Pusher Props or Counter Rotating, are never necessary in single motor applications. The beauty of brushless motors is that they can spin clockwise or counter clockwise. i.e. either direction. So that means you can use pusher and or regular props since the motor can spin either way. You will need to be sure you have the motor spinning the correct diction.
That is done by the ESC / speed controller and or swapping any 2 of the 3 wires from the ESC to the Motor. If that is confusing, all our Brushless Speed Controller Manuals explain that a bit better.
Remember, the prop lettering ALWAYS faces the direction of flight. Even of the motor is in the very rear of the airplane, the letter faces the direction of flight. If the ParkJet motor is in the middle, the letter faces the direction of flight.
The GraysonHobby ParkJets are very powerful and will fly most airplanes with the prop on backwards. So if you parkjeft feels sluggish, try reversing the direction of the prop, I bet that fixes it.