I was flying with my nephew, we were flying a Great Planescub with an OS70 four stroke in it,put on glow ignnitor and started engine,engine was running about half throttle.We were not sure why, we had no response when we moved the throttle stick,then noticed we didnt turn on the battery switch. as I was yelling at him for not turning on the switch I put my hand into the prop when I went to turn on the switch,wasnt thinking . Gave me a good whack across three fingers hurt for 2 weeks. Now I keep calm when things arent right and dont yell at anyone.</p>