Like, ya know, when that thing that makes you move, it has pistons and things, When your thingamajigy is providing power, you do not hear other peoples thingamajig when they are providing power. HiTech
speaking of spitfire, what type is in this vid? it has 5 props...http://www.youtube.com/watch?v=_vmEiZiuooc&feature=related