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Unread 12-03-22, 12:51 PM
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Excellent news!

As I understand it, the most efficient propellor in cruise has ONE blade, as that represents the least drag, but has terrible static thrust (will take a long time to gain speed from standstill or to climb).

There actually have been single blade balanced experimental props.

https://en.wikipedia.org/wiki/Single...e%20powerplant.

Two blades are obviously more nicely balanced, at least aesthetically.

Three blades will give more static thrust. From a standstill, able to move more air per rotation, so are able to accelerate the aircraft (or climb) a wee bit faster as they can produce more pressure. BUT, in theory, 3 blades should be slower in cruise than two, as one now has to drag three blades through the same air (rotationally).

That's why heavy turbprops will go to four blades. They can accelerate / climb the aircraft faster than fewer blades, where speed or absolute efficiency are less a priority.

That all said, I would think 3 blades dynamically balanced would tend to break up engine pulse vibrations and should result in a slightly smoother ride.

However, a good dynamically balanced prop (on the airplane) should get close to the same results.
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