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### Does a 4 bladed prop have almost twice the thrust of a 2 bladed prop?

Does a 4 bladed prop have almost twice the thrust of a 2 bladed prop? As a general rule, I'm told GA planes generate 4 lbs of thrust per horsepower. (Source: Zenith School of Airplane Design, Flying ...
130 views

### Is there any equation on propeller thrust that takes into account the number of blades [duplicate]

I had a look at both What is the equation for calculating static thrust? and Is there any equation to bind velocity, thrust and power? However, it does not mention how much would the thrust be ...
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### Why Consumer Drones don't use multi-blade (more than 2) propellers?

Maybe unusual question but it's related to Aviation world, even if is more directly related to Drones one. Why almost all consumer drones like DJI's and Yuneec's ones (but it's true also for other ...
1k views

### Is there a mathematical formula to find the most efficient propeller? [duplicate]

Is there a mathematical formula to find the most efficient propeller? Is a five-blade better than a four-blade? Does software exist to aid in the calculations there?
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### Why are three-bladed helicopters relatively rare?

I admit that this observation is entirely subjective, but it seems to me that there three-bladed rotors are significantly less popular than two or four. Factors that I'm guessing contribute - ...
8k views

### How to calculate the thrust of a piston or turboprop engine? [duplicate]

This spawns from a related question. Propeller-drive engines (piston/turboprops) seem to always list their output in horsepower or kilowatts, which are units of power. I want to know the engine's ...
13k views

### How does a fan differ from a propeller?

Why is the fan in a turbofan different than a propeller in a small airplane? Why do propellers typically have 2 or 3 blades, but the fan has a lot more? And why is the fan shrouded but the propeller ...
29k views

I have heard that propellers with more than four blades are not as efficient as 4 or less blades because of lower thrust which may result from interfering prop-streams. But I see the ATR-42/72 and ...
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### Why is the Tu-95 so efficient despite having propellers that spin faster than the speed of sound?

I've ready many, many times that propellers are not efficient near the speed of sound because it's so hard to get a tip-speed above Mach 1. Then I came across this: It's the Tu-95 "Bear", a ...