Know thy enemy - Tractor Drivers
Thought this might be useful info. Second dual lesson with student on Cessna 150. Engine start normal except that he had throttle slightly too far open and RPM hovering around 1300. I Suggested that he reduce power to 1000 RPM. Without warning he shoved the throttle wide open to full power before I could blink an eye. Seneca parked 14 metres ahead. Instructor (self) managed to apply hard brakes and got hand over his fist and got throttle back asap.
Aircraft had leapt forward three feet before I stopped it. Student had applied park brake prior start, but as you know there is no definate method of knowing in the C150 if the park brake is set or not, as knob is always flush with panel. In this case park brake had not been set properly.
Student, who is a farmer type, went white and apologized with sickly smile. He explained that he was used to driving tractors where to reduce power you PUSH THE THROTTLE FORWARD! Later we were cleared for immediate take off and this time whacked the throttle back to idle (which he thought was full power)instead of pushing it forward.
Moral of this story. Good idea to quiz student on his occupation before teaching him to fly. If tractor driver, treat him with extreme caution when taxying.