A paradox...

[iacob alex]

    ...can be the simplicity of the well known two blades propeller.
      This one,is a good performer,in a flowing medium(air,water) ,as a driver (thrusting the fluidic medium),or as a follower (collecting a fluidic mass thrust).
       By the way,a man in Italy,is flying his small airplane,with a one blade(only!) propeller.
       So,why we must imagine a merely follower/gravity power collector,in a so sophisticated manner?
              Sometimes,less is more.
                     All the Bests!  /  Alex

[xpenzif]

I don't know which you are trying to say here. Less is more sophisticated, or Less can give more performance?

[iacob alex]

     Hi Xpenzif!
The answer is "less can give more performance".
A basic design begins with a "fit" prime line.
A successful device,engine,thing has a minimal "fit" number of spare parts.
An one blade propeller ,you can look up to  some falling seeds in the natural world.
It's a long,long time suggestion "in the air".
               All the Bests!  /  Alex

[xpenzif]

I also prefer simple machines over more complex ones, provided they can accomplish the same task. I dont think that less is giving more performance in this design though. On a 1-bladed prop, the counterweight has to be shifted/adjusted to counterbalance the bending movement from the thrust on the blade. It would also have to be shifted to counteract the drag of the blade. The blade will get different ammounts of drag with different rpms, so I think the position of the counterweight would have to be changed according to the rpm. It would be difficult to exactly balance the loads on the single blade, and you can only come close at one specific combination of rpm, airspeed and power, which means you will get vibration.
An equal blade on the other side would make this device so much simpler.

[iacob alex]

    Hi  Xpenzif !
Regarding one-blade propeller,if you type these words on Google,you can find a plenty of data.
   The problem of "less",can be seen as a mini-max knotty point,in  connection with any design,this time with the gravity powered devices.
    My point of view is explained in some topics(let's say "Wheel vs. lever").
       
                 All the Bests!  /  Alex