At 06:16 AM 2/13/2015, you wrote: >Two props = nearly twice the thrust? +++++++++++++++++++++++++++++
There is no free lunch. Each prop would have to be pitched to half the load of a single prop for the engine to turn the same rpm and produce equal power. The additional belt drive setup would rob additional horse power so you end up actually losing power over a single prop. Also, a single larger prop would be more efficient than two smaller props. Your tail / rudder would have to be enlarged to handle adverse yaw in case of one side failure. Still wonder why it's never been done? Larry Flesner
