Originally Posted by MentalAvenger

The Beachcraft Starship (designed by Burt Rutan ) used a turboprop engine which had the propeller behind the engine. One of the features of this design is that the air flowing over the engine nacelle is compressed as it approaches the prop. So is the air/exhaust from the turbine engine itself. The prop is biting into higher density air, and therefore should be able to provide more thrust in this configuration.