Rotor Thrust

Screw

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Alright!  I'm pulling my pants down.  <br><br>I understand the advancing blade, retreating blade, and hinging such that we get equal lift.<br><br>I don't understand how a non powered rotor produces rotor thrust.  Or how the rotor spinning is producing thrust?  Am I missing the relationship between lift and thrust?  What is Rotor Thrust?<br>
 

ToddP

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Re: Rotor Thrust

John,<br><br>for these kinds of questions we need people like Chuck Beatty and Doug Riley.  I haven't seen them here yet.  Quick, somebody go get them!!  ;D
 

Aussie_Paul

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Re: Rotor Thrust

John, untill we get the big guns here, rotor lift and rotor thrust for all intents and purposes are the same.<br><br>Aussie Paul.
 

mceagle

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Re: Rotor Thrust

John,<br>You are right in your asumption that a non-powered rotor cannot produce thrust. However in our case the rotor is powered by inflow of air, from below the blades (autorotation). <br>Being powered, the rotors are just as capable of producing thrust as a propeller.<br><br>Regards Tim McClure
 

DougKspokane

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Re: Rotor Thrust

(Just a reminder, I'm a newbie and a little simple, but I've doing a lot of reading on the sites so...)  I thought that the gyrocopter rotor produced LIFT not Thrust ???.  Thrust comes from the engine/propeller, yes?  no?  This is not a helicopter which has to do both with the rotor, right?
 

Udi

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Re: Rotor Thrust

Don't confuse Lift with Thrust.  Thrust is a force produced by a propeller (or by jet for that matter).  Both your engine propeller and your rotor are producing thrust.  The engine thrust is pushing you forward, and the rotor thrust is pulling you up and a little backwards.<br><br>Lift is the vector of the rotor thrust, which is opposite to gravity.  The rotor thrust line, which is tilted a little backwards in a gyroplane, can be divided into two "imaginary" vectors: Lift and Drag.  <br><br>The rotor achieves rotation by the air flowing through it.  The rotation itself is producing thrust, just like any other propeller.<br><br>Udi<br>
 

Screw

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Re: Rotor Thrust

Thanks All,<br><br>The whole world makes sence again ;D<br>
 

Thumpernator

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Re: Rotor Thrust

Udi has it "nailed."<br><br>Also, remember that the rotor thrust line (vector) is always perpendicular to the rotor tip plane.<br><br>So, when you read a post by Chuck B. or Doug R., etc, and they mention the relationship of the rotor thrust line to the CG, you'll know what they are talking about.<br><br>Also, please don't pull your pants down.  [glow=red,2,300]"Homey don't play that."[/glow]
 

rehler

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Gyro Rotor Thrust?

Gyro Rotor Thrust?

Can't see how it works?

An easy way to visualize how a "driven" gyro rotor produces "thrust" is to see the air moving up through the center portion of the rotor (inner 2/3rds of the blades) causing the blades to turn like a windmill. Then the outer portion (outer 1/3rd), that is going much faster, is being turned by this inner area to produce thrust just like a helicopter by pushing the air down.

Center portion being driven by the air (no thrust). Outer portion being driven by the inner portion producing thrust.

The 1/3rd point is not an abrupt change. It is just that the outer few inches are really turning fast and producing a lot of thrust and it becomes less and less as the point moves inward towards the center until at about the 1/3rd point it stops producing thrust and from that point in it starts to act more and more as a windmill to turn the rotor blades.
 

Harry_S.

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Re:Rotor Thrust

ROTOR THRUST!!

Next time your out flying, pick out a grassy area that had been mowed 2-3 days before or a nice dry dirt (dusty) spot & make a zero roll landing.

You won't like all the dead grass clippings and/or dust getting all over you and your pretty gyro. Where did all that downwash come from?
 
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