The most efficient prop is a single-bladed prop. The problem is that they're impossible to balance. So two blades are the minimum. Any more than that and efficiency goes down with each additional blade. Two blades are faster than 3, and they make shorter takeoffs. The advantage of 3 blades is greater ground clearance, ...a consideration on rough, gravel strips. They are not quieter. They are more expensive to overhaul.
Oops. Poor sentence structure makes a misrepresentation,.... The 3 blade prop will make a slightly shorter takeoff than a 2 bladed prop, but ...2 blades are faster in cruise. 3 blades are not quieter, but give greater ground clearance. 3 blades cost more to overhaul than 2 blades.
3 blades perform better less vibration and they are quieter (smaller dia. means,less tip speed)more mass less vib. if you want efficiency stay with 2blades, but if you performace 3 be the way to go
Actually, Ron, 3 blades weigh more than typical 2 blade props. They are not quieter, they only change the frequency of the sound to a higher Hz. They actually make more noise in decibels due to the fact that you now have 3 noisemakers instead of 2.
