Get ready for the seven-bladed prop from MT-Propeller of Germany. Already being tested on a Piper Cheyenne.
Apparently, more blades allows lower rpm gearboxes reducing blade tip drag. The number of blades, diameter, twist, chord, and thickness distribution all determine propeller efficiency which is driven by the lift distribution along the blade radius and the airfoils. Most modern designs have been designed with reduced lift at the tip reducing the vortex.
An interesting statement in the article I am reading about the 7-bladed prop is a quote in the article by a spokesman...."Everybody told us it's not possible"......."They said it was dangerous;that fuel control units will go into resonance and King Air's will crash ".
Anybody have more details about FCU resonance and number of prop blades?