What is the best prop location for distributed propulsion - pusher, tractor or mid top wing ( blown flap) for an ultralight, max speed about 60mph, for MINIMUM takeoff distance ( 20-40') and about 15mph stall speed?
I would assume Blown flap, as the wing and prop would see clean air, and the flap sees the highest air speed increase due to exit speed of the prop, assuming 100% coverage.
My assumptions are:
Tractor configuration: entire wings sees prop exit speed but air is turbulent, so less lift, prop is in clean air, so max thrust.
Blown flap (prop on top of wing): wing is in clean air, so max lift, flap sees highest increase in air speed in this configuration, so max lift, prop is in clean air, so max thrust.
Pusher configuration: wing and flap in clean air, so good lift, prop in dirty air, so less thrust
Is this correct?