Gentlemen,
With all the research done and being done on very high tech military and commercial propeller driven aircraft, it is the overwhelming predominance that the choice by a huge majority is the "TRACTOR" propeller configuration. This alone says something about "EFFICIENCY" of the tractor configuration since military and commercial aircraft are always focusing on efficiency for speed and range. It is must be the "clean" air encountered by the tractor prop versus the "dirty" air (airframe induced turbulence) encountered by the pusher prop. The prop is a very high speed airfoil and it thrives on clean air hitting the prop blades for maximum efficiency. The monstrous B-36 bomber and the UAV Predator are the notable pusher military designs that went into full production for the military. Everything else are tractor props including the fastest propeller driven WWII fighter which is the XP-47J with a top speed of 505 mph. Tractor props dominate in both military and commercial designs due to inherent efficiency and ease of airframe accomodating the forward mounted engine.
Thanks
larry<br type="_moz"/>