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C. Beaty

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Eddie, the rpm of a rotor depends upon the load that it’s supporting. I’m sure you’ve observed that with 2 people in your RAF, the rotor spins a bit faster than it does solo. The rotor has to speed up to carry your passenger; if it didn’t, it wouldn’t.

As you shoot a landing, you initially follow an angled, generally straight line path toward the ground; as you get closer to the ground, you begin pulling the stick back to slow your descent; the landing flare. During the flare, the load on the rotor increases and if it’s a properly designed rotor, neither tail heavy or nose heavy, the rotor rpm increases to handle the increased load. If it didn’t,. you’d fall through.

There you have it; a high inertia rotor that doesn’t have some built in collective via tail heaviness will fall through unless you use a longer flare and give the rotor enough time to accelerate. Or, as I’ve mentioned earlier about flying with high inertia Hughes OH-6 blades, you roll out of a tight turn close to the ground and use the excess rpm to float for a bit.

Rotors don’t slow down unless the load is reduced. Normally, that happens after the wheels touch the ground.
 

fara

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C. Beaty;n1131139 said:
More technobabble and double talk. Center of pressure and aerodynamic center are one and the same on zero pitching moment airfoils, regardless of airspeed, in the subsonic range.

This discussion was about the effect of moment of inertia on the landing behavior of gyroplanes with fixed pitch rotors. High inertia rotors fall through unless they have pseudo collective pitch via tail heaviness.

There is no other way a rotor can produce an increase of lift to cushion a landing except by increasing its rpm or by collective pitch.

During the landing flare, a tail heavy rotor blade twists noseup, a form of pseudo collective pitch.

JC’s measurements of rotor rpm in a 55 degree coordinated turn indicate a considerable amount of dynamic twist in Averso rotors.
Regardless of airspeed? Airspeed and angle of attack are very different things. I specifically talked about angle of attack just to be clear.
https://en.wikipedia.org/wiki/Pitching_moment

I would think your next favorite gyroplane airfoil should be symmetrical so its AC and CP are indeed exactly on each other regardless of AoA. Let me know how stable it behaves on a gyroplane. I really don't know but I have a suspicion it would require a good amount of reflex or some other trick effecting its efficiency

I really do not know how much exactly rotor RPM on an Averso changes at 55 degree coordinated bank turn. According to JC it went from 340 to 390 RRPM when he wanted to see it go to 450 RRPM. What is happening to the blade element at the tip in terms of airspeed?
And if it doesn't and it exhibits collective pitch as you call it. Well good. Its pretty freaking nice and it works and so far I am lost at finding any Averso rotors falling out of the sky or even cracking. You should try it sometime. Your equating Averso to McCutchen was a bad joke and evidence that you have never flown them much at all. Reasonable high inertia rotors are nice, smooth and have good hang time. Averso is slightly tail heavy you say giving them collective pitch. Ok. Magni nose heavy you say. Ok. Beyond heavy stick what does the nose heaviness give them? Not collective pitch the same way as tail heaviness I hope. Both have way better hang time than low inertia Dragon wings. Easy experiment to do. Fly a Magni. Fly an AR-1 with Averso. Fly a Dominator 2 seater at same load and day with Dragon wings. Then let me know.
You say Magni nose heaviness in rotors is the main key to its heavy control forces and Averso being tail heavy should be light pressure. Averso stick pressure is not light. Its reasonable. Its response is immediate but there is definite center and it requires pressure to move it. I suspect that this very defined and definite center has been responsible for a bunch of accidents in older gyroplanes possibly leading to PIOs at high speeds and causing buntovers while many old schoolers celebrated "sporty" feel of touchy undefined neutral gyroplane sticks.
 
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C. Beaty

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The junior high school arithmetic is simple; a coordinated turn at a 55 degree bank angle imposes a load of 1.75 Gs. Rotor rpm varies as the square root of load which should result in a rotor speed of 450 rpm if the 1G rpm is 340. No mystery.
 

fara

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C. Beaty;n1131153 said:
The junior high school arithmetic is simple; a coordinated turn at a 55 degree bank angle imposes a load of 1.75 Gs. Rotor rpm varies as the square root of load which should result in a rotor speed of 450 rpm if the 1G rpm is 340. No mystery.
Assuming we accept that it really goes to 390 RRPM and JC really had a coordinated 55 degree bank turn without losing airspeed and any altitude at all. The only way to know is to take a G meter, a rotor RPM meter and a video camera and record both values and see if at 1.75 G what the RRPM was exactly at the same time stamp. You know how many people told me that they had done a 3 G 70 degree bank turn in a trike till you look at the EFIS log of the flight. Nether the AoB was 70 nor was the peak load factor 3. Most people took slightly less than 60 degrees and less than 2 G to be 70 and 3. Just saying. After doing 5 different aircraft, I never trust a video camera from inside for angle of bank and never my body feel for measurement of G. Better to use a G meter along with a rotor RPM gauge in the same focus view and create G load of 1.75 and see what RRPM say at the same time.
If it was say 45 degree sustained bank instead of 55 or a little tiny altitude was being lost during a turn, you have 1.4 G and sq. rt of 1.4 is 1.18 x 390 (RRPM at 1 G) = 402 RRPM (pretty close within error margin of cheap RPM gauges we all use)

Ok aside from all that, assuming JC and you are even right; what is bad about reduced RPM with positive pitch change then; assuming it happens to the extent claimed. Certainly nothing divergent or you'd have some evidence of it elsewhere like you clearly do in McCutchens.
 
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All_In

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Well I'm learning more from the experts but not at there level. Have 100 questions but it would just slow down their discussion. It's sure making me do a lot of research and math. Thank god I found a formula online calculator that seems to work. Now I'm going back to the begging and reread all of their comments in hopes I can learn more now that I know a little more than when I read it the first time.
 

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My posts may seem like arguing.

But I'm one of those people who posts in public what I believe to be the truth. If I'm right fine, no joy there. But if I'm wrong and learn the truth WOW that is GREAT and exactly what I'm hoping for just to learn.
Say a word I do not know and I will ask what it means and do not care if it makes me look stupid or foolish because now I know/understand.

Vance is one of my hero's he spends the most valuable thing there is TIME answering questions which makes the world a better place and for all he's done in life and then overcoming disability that completely stopped others from having much of a life.

But he's the only person who drives me crazy with is WRITTEN answers to ME.

I've learned a lot from him when he posts to others but when it to me his written answers NEVER have let me understand and be able to tell others why either. There is no new opinion it always so vague like "It's the some of the parts." Now how do explain how anything works to others when it such a vague anwser.

Yet I love the guy and we talk on the phone many times. I've sent him many students and I found out today he sent me a chapter member who may buy the Pitbul converted to a tricycle gear which I now call a TriBul. So PRA 31 has gone tribal.

This morning he called me to help me understand my post on this thread.

Wow what a difference talking to him makes instead of reading "the some of the parts" and no real answers to on the phone and explaining specific real simple answers.

OK so now please correct this for me...

Here is what I learned today about landing flares:
After talking to Vance on the phone and then doing some math = it's the LIMITED TIME FRAME in both flares and zero G events.

His simple anwser was it the short time frame = just do the math.

Of course the physics is correct as is the opinion.
But the time frame is so small. A few seconds that their isn't that much time to spin up faster, but lighter blades do of course, or that much time to spin down either heaver last longer just as physic proves.
That's why there are no more accidents in either type of blades the time frame is too small unless the pilot flared way too high adding enough time to really hit hard and do any real damage.
This I would have learned with more experience and less theory.

As to why the helicopter engine is not the same as the wind. It is of course to drive the blades. But Gyro planes self regulate depending on the density altitude and the load it is carrying.
I understood this fact and applied it to a zero G event. Of course Low inertia blades spins up faster but for a very short time frame until they are up to speed again = if you cut power and enter a vertical decent.
Likewise if both low and high inertia blades enter a zero G event for a SMALL duration of time the high inertia blades will not have slowed down as much when they reach the top and the low inertia blades will only slow down a little in a short period of time.

But the main reason it's not like a helicopter is because helicopters have to stay in a very narrow RPM range and gyroplanes RPM are automatic and depends on the density altitude and the load it carrying.

So yes the wind is like an engine but RPM in gyros are automatic and uncoupled. In my example of zero G events the time frame is too small unless you stay in a zero G event too long increasing the time frame so either high to low inertia blades are adversely effected by the event in such a short period of time.
 
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Jean Claude

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fara;n1131154 said:
Assuming we accept that it really goes to 390 RRPM and JC really had a coordinated 55 degree bank turn without losing airspeed and any altitude at all. The only way to know is to take a G meter, a rotor RPM meter and a video camera and record both values and see if at 1.75 G what the RRPM was exactly at the same time stamp. After doing 5 different aircraft, I never trust a video camera from inside for angle of bank and never my body feel for measurement of G. Better to use a G meter along with a rotor RPM gauge in the same focus view and create G load of 1.75 and see what RRPM say at the same time.
.
Yes Abid, vidéo not shows me the bank degrees. It just shows the constancy of this angle.
But then, you can deduces the "G"s with the mean forward speed and the time to make a complete turn according to the ground mark. You can see all that yourself on the same view. Sans titre.png

One more thing: There is no need of altitude with no changing: A regular descent has never affected the "g"s
Ok aside from all that, assuming JC and you are even right; what is bad about reduced RPM with positive pitch change then; assuming it happens to the extent claimed. Certainly nothing divergent or you'd have some evidence of it elsewhere like you clearly do in McCutchens.
It is easy to understand how the heavy tail can produce divergence if the torsional stiffness is too low. That's why I mentioned the stiffness of the Averso blades


Sorry: GC for Gravity Center
AC for Aerod. Center. It is also the pressure center when Cm0 =0 , as Chuck said
 
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fara

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Hi JC
i think you will be surprised that when you are banking if there is any descent it’s not steady usually and it does have an effect on Gs. This of course is for any Aircraft. Having done test scripts and plans for multiple ones you’d have to be a hell of a precision pilot to be sure your descent did not effect Gs in a turn. In this scenario for you to make the claim you make; the right way of measurement is a direct measurement of G and RRPM. Then you have something solid. Chris in his Arrowcopter has an EFIS and if he has the AHRS sensors, he can put a screen on it that just shows Gs and RRPM. Of course rotors are Averso on Arrowcopter. I wonder if Chris would do that for us.

Yes the torsional stiffness of Averso is pretty darn good and there is no divergence throughout achievable speed range. So this discussion is such a theoretical frog hair that it’s useless.

I am am disappointed that Chuck has such an ego and a closed mind that unless Xavier completely made the rotor like he wants he has to call it names and equate it to a dangerous rotor system like Skywheels. Every airplane wing has pitching moment in the airfoil and it changes with different AoA and we have to find the worse case scenario. Airplane itself has possible pitching moments (like high thrust line in a Searey) and them we balance all of that with the right tail for worst scenario though not for wings coming off. And if Averso and Magni both show what I term has good hang time in a flare compared to say Dragon wings and one is tail heavy and one is nose heavy then of course you and Chuck are missing something from the whole picture and the reasoning of collective pitch effect on Averso alone does not add up because Magni should not have that being nose heavy per Chuck’s claim. When theory does not jive with reality we don’t discard reality, we recognize our theory is incomplete or defective in some way and confirm results by experiments. Of course that must be “silly”. I however have to admit that Averso do show a better hang time than even Magni rotors and I have wondered how that is. I understand that this slight tail heaviness might be contributing this collective pitch effect making them do that. That indeed might be adding on to it. If so if I design my own blades for Gyroplanes with fixed pitch, you can bet I am placing CG/GC slightly behind 25%. No replacement for what behaves and performs good for the pilot. Who cares if it’s at 26% or 30% if the torsional rigidity in construction is there and the desired effect is pretty nice in landing flare.

Anyway thanks for the respectful indulgence. I will see if I can do a G measurement with Rotor RPM on Barry Maggios machine as he has an EFIS also if the weather is good this weekend and verify your claim with Averso rotors.
 
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C. Beaty

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The primary source of feedback into the stick comes from the use of the Bensen offset gimbal rotorhead. As a result of the offset, a component of rotor thrust serves to guide the pilot. The rate of response affects stick stiffness but does not affect steady state response A high inertia rotor lags stick input, causing a stiff stick, a low inertia rotor follows with less lag, causing a soft stick.

The only gyroplanes to receive FAA certification post WWII were the A&S-18A and the McCullogh J-2. Both used feathering cyclic control via swashplates and both used properly balanced symmetrical airfoils; the 18A the NACA 0012 and the J-2 the NACA 0015. There is no feedback of a component of rotor thrust into the stick when a swashplate cyclic control system is used but neither had reputations as killers.

Needless to say, modern rotorcraft airfoils offer some lift/drag improvement over symmetrical airfoils.

I’ve flown several gyros with swashplate cyclic control and didn’t tumble out of the air.

If Abid had a bit of engineer training, including some math and physics, he wouldn’t find it so difficult to understand how a rotor works.
 

fara

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C. Beaty;n1131163 said:
The primary source of feedback into the stick comes from the use of the Bensen offset gimbal rotorhead. As a result of the offset, a component of rotor thrust serves to guide the pilot. The rate of response affects stick stiffness but does not affect steady state response A high inertia rotor lags stick input, causing a stiff stick, a low inertia rotor follows with less lag, causing a soft stick.

The only gyroplanes to receive FAA certification post WWII were the A&S-18A and the McCullogh J-2. Both used feathering cyclic control via swashplates and both used properly balanced symmetrical airfoils; the 18A the NACA 0012 and the J-2 the NACA 0015. There is no feedback of a component of rotor thrust into the stick when a swashplate cyclic control system is used but neither had reputations as killers.

Needless to say, modern rotorcraft airfoils offer some lift/drag improvement over symmetrical airfoils.

I’ve flown several gyros with swashplate cyclic control and didn’t tumble out of the air.

If Abid had a bit of engineer training, including some math and physics, he wouldn’t find it so difficult to understand how a rotor works.
Right. To be more relevant lets stick with teetering rotors and no swash plate and there plenty have had PIOs including in Dominators. There was a fatality a couple of years back in Florida because the guys training was not in a Dominator but an MTO and without a bunch of training the feedback isn't great and he PIOed and went right into the ground. Getting reasonable feedback isn't a bad thing. Its a good thing especially for new gyroplane pilots.

Helicopter airfoils work in a different range of AoA and have different use. I don't claim to be an expert on helicopter airfoils by any means but I also know now that you have never flown Averso rotors and your completely left field comparison of them to Skywheels was almost laughable if it did not come from someone with your book knowledge. You got to refrain from making such judgments till you know more about them. Admittedly, if there is this collective pitch effect (which is not a phenomenon described by any helicopter book I have read) in Averso or tail side heavy blades for a teetering fixed pitch gyro rotor system, I think that's a desirable effect.

Chuck, you are full of contradictions in your approach to gyroplanes. You call them toys. You don't believe in their capabilities beyond that. No XC etc. Yet you want to use the latest helicopter airfoils on their teetering fixed pitch rotors? For what. Its not like we are making transport class 12 seat helicopters here. It almost seems like you want people to do the experiments for you because that entertains you. This is contrary to how I approach them which is as a product which has a market which right now is mostly recreational private 2 seater market. If our gyroplane is already able to go 100 knots straight and level pedal to the metal and can remain steady as a rock there, why do I need to spend more time and resources for what I want to achieve. I am already there.
Now if US Army came to me with unlimited budget and gave me some criteria that I can't fulfill with what I have, I will obviously look to do something different. You want Wachula cow pasture flying done with the latest helicopter airfoil that gives you maximum 2 percent more efficiency gain on the whole aircraft. That sucker's name is Ernie Boyette, not Abid. With apologies to Ernie and Mike.
 

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All_In;n1131156 said:
My posts may seem like arguing.

OK so now please correct this for me...

Here is what I learned today about landing flares:
After talking to Vance on the phone and then doing some math = it's the LIMITED TIME FRAME in both flares and zero G events.

His simple anwser was it the short time frame = just do the math.

Of course the physics is correct as is the opinion.
But the time frame is so small. A few seconds that their isn't that much time to spin up faster, but lighter blades do of course, or that much time to spin down either heaver last longer just as physic proves.
That's why there are no more accidents in either type of blades the time frame is too small unless the pilot flared way too high adding enough time to really hit hard and do any real damage.
This I would have learned with more experience and less theory.

As to why the helicopter engine is not the same as the wind. It is of course to drive the blades. But Gyro planes self regulate depending on the density altitude and the load it is carrying.
I understood this fact and applied it to a zero G event. Of course Low inertia blades spins up faster but for a very short time frame until they are up to speed again = if you cut power and enter a vertical decent.
Likewise if both low and high inertia blades enter a zero G event for a SMALL duration of time the high inertia blades will not have slowed down as much when they reach the top and the low inertia blades will only slow down a little in a short period of time.

But the main reason it's not like a helicopter is because helicopters have to stay in a very narrow RPM range and gyroplanes RPM are automatic and depends on the density altitude and the load it carrying.

So yes the wind is like an engine but RPM in gyros are automatic and uncoupled. In my example of zero G events the time frame is too small unless you stay in a zero G event too long increasing the time frame so either high to low inertia blades are adversely effected by the event in such a short period of time.
Your latest writing looks right to me John.

In my opinion a zero G event in a gyroplane is a very rare occurrence and I have found it difficult to get below .6 Gs.

I feel there are few black and white answers because everything is a compromise and the systems are interdependent and work in concert.

How I optimize a particular landing for a particular gyroplane is affected by many more things than high or low inertia blades.

Things that affect the procedure for an optimized landing in no particular order: high or low inertia blades, the horizontal stabilizer, the thrust line in relation to horizontal stabilizer, the ground in relation to the horizontal stabilizer, the effectiveness of the vertical stabilizer and rudder, a full flying rudder as opposed to a vertical stabilizer and rudder, the suspension, the aerodynamics of the aircraft shell, the characteristics of the rotor blade airfoil, the available power, the thrust line in relation to the center of gravity, the propeller, the goals of the landing, the rotor control linkage and how the aircraft is steered, the current loading and center of gravity.

Many things outside the aircraft affect the procedure for the optimized landing: the density altitude, wind, turbulence, proximity of obstacles to the wind, the landing surface, the proximity of the wind sock, what the wind sock is telling me, how well I am flying today, the needs of ATC or other traffic at a non-towered and where I want to turn out.

If I have a low time client I extend the downwind leg so they have a stabilized approach.

In my opinion the reason to practice is so you have tools to manage all these variables and still come up with a satisfactory landing.

I have well over 2,000 landings in my log book and I still learn from every one.

The best landing and takeoff procedure will be different for each gyroplane.

Every landing and takeoff is unique.

In my opinion a low G event is to be avoided and should not happen often enough to develop a procedure. A high inertia rotor will reduce rpm more slowly and recover from low rpm more slowly. I would not suggest that the blade inertia makes a difference in the outcome of a low g event.

I find the more I learn the less black and white the world seems and the harder it is to be definitive in the answer to a question. I often don’t understand the original question and struggle to find the source of the confusion.
 
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C. Beaty

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I had a close encounter with Skywheels rotors on a Dreadnaught class gyro a number of years ago which I related several days ago here on the forum. But on a light gyro, their behavior is similar to Averso rotors on a Dreadnaught.

Pilots of light gyro used to rave about Skywheels and how they floated for a landing and like Abid, mistaking high inertia for the effect of tail heaviness and the resultant pseudo collective pitch.
 

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I'm mostly sitting here enjoying my popcorn, but I wanted to interject a question:

In evaluating how much a rotor will "fall through" a landing or how quickly G-loads will speed it up, doesn't the airfoil, and especially the twist in Dragon Wings make any comparison to 8H12-ish blades oranges-to-apples? My understanding has been that the efficiency benefit of the twist had a downside in more sluggish autorotative response.
 

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The lift distribution along an untwisted gyro rotor blade is far from ideal; the advancing blade tip often operating at negative lift and the inboard sections stalled.
Twist provides more uniform lift distribution and improves rotor efficiency. If anything, it will slightly improve landing performance.
Helicopter twist is detrimental to autorotative performance but gyro rotors are twisted in the opposite direction since the airflow through the rotor is the reverse of helicopter flow..
Here’s the flow distribution along an untwisted Cierva rotor blade during a vertical descent as calculated by Prof. JAJ Bennett, Cierva’s chief engineer at the time:

lift distribution 001.jpg
 
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Vance
Hi Buddy.

Thank you so much Vance. From now on I'm calling you on the phone and getting the simple anwser that match the physics.

For newbies: The small number of accidents we have from flaring is the same in all models of blades!!!
You let the modern manufacture test and select the blades.

But you have to put all theory into the real world flaring landing statistical accident risk.

When the rate is the SAME in all models it shows it's the PILOT NOT THE BLADES you select or sale.

I'm not going to buy a set of high inertia blades to compensate for my bad landing piloting skills as a newbie.

Get extra TRAINING so it is automatic to flare like the pros do for zero roll landings.

Building experience time/hours with horses and machines they become an extension of your body. You know what I mean?

When I have logged many hours and that day comes I do not want my Genesis to float past the spot landing contests as I've observed with high inertia blades even with experts pilots flying when the wind changes and sometimes even balloon up when either carrying too much speed or the winds gusts etc.

Get more training it's cheaper than bad piloting compared to paying to repair yourself and the rotorcraft so you have the skills which will them make these theories much to do about nothing that really is a problem for a skilled pilot.
 
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C. Beaty;n1131168 said:
I had a close encounter with Skywheels rotors on a Dreadnaught class gyro a number of years ago which I related several days ago here on the forum. But on a light gyro, their behavior is similar to Averso rotors on a Dreadnaught.

Pilots of light gyro used to rave about Skywheels and how they floated for a landing and like Abid, mistaking high inertia for the effect of tail heaviness and the resultant pseudo collective pitch.
Chuck. Skywheels problem is structural engineering of the blades. They could easily be fixed with correct structure and bracing internally. I offered some help in that to McCutchen upon looking at how they drooped and how flexy they seemed and got a negative response of something to the effect that he was making rotor blades when I was in grade school and then a few days later when we actually flew it, they showed divergence from hell but only past 60 knots but got really bad at 75 knots or so. One up, two up, low fuel, full fuel did not seem to matter. Speed mattered. They wanted to pitch up and turn hard. At 75 knots to go straight, the cyclic was pushed to the front and to the side all the way to the stop.

We have flown Averso Stella 28.2 foot and 28.8 foot rotors to a full 1260+ pounds gross weight to 120 knots. They are solid and have no diverging tendencies to show. If the structure can handle the torsional load, that would be the result. In any case, I can assure you in landing flare they are the best rotors I have seen and that certainly includes Dragon wings. Dragon wings actually are quite the opposite honestly. You better get the flare right because that is the only chance you are going to get.

According to Greg, he has yanked and banked 23 foot Dragon wings plenty on his single seat Air-Command and at 60 degree bank coordinated turns and more and he has never touched 500 rotor RPM which is where he should be according to you and JC. So are Dragon wings also tail heavy or high inertia (not). Also why do Magni rotors also have a pretty decent hang time (though not like Averso) since they are nose heavy as you say.
 
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C. Beaty

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Maybe someone has monkeyed with the trailing edge tab and given them a slight positive Cmo. Nothing to be concerned about, it’s not dangerous.
 

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Watch the time to go from 340 to 390 rpm in my video, Abid
You can understand how long it will take to go from 340 to 450 rpm.
If the turn does not last long enough, then you will not see all the expected rrpm increase
 

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Jean Claude;n1131208 said:
Watch the time to go from 340 to 390 rpm in my video, Abid
You can understand how long it will take to go from 340 to 450 rpm.
If the turn does not last long enough, then you will not see all the expected rrpm increase
Hi JC:
My apologies. I must have missed something. Did you post a video link?
I just saw a picture you had posted.
 

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200+
fara;n1131062 said:
Yes and Greg and me tried to get them tested on AR-1. Paid for teeter tower changes to use them. Ernie brought them over. They were flown and did not perform as well. We wanted to work with them more but they were taken back and could not be left overnight with us. Couple of weeks later the blades were advertised for general release. If what we saw of them was the final release, they were heavier overall than Averso and performed worse.
Yes Bulldozers do not fly, I know. Good luck with it Chuck. The problem with this type of attitude is that market will leave you and Ernie behind. I hope you guys change most importantly your attitude and snobbery. I would have lioved to use US made rotors but not this way. I am sure Xavier Averso and Pascal appreciate your calling their rotors bulldozers quite nice when the rotors you are pushing were in fact heavier
Abid,
First of all sir. I consider you a friend however let’s get a couple of things straight. I was there when Greg test flew my Dad’s new Big blades. They are not the standard DW’s. They are a different airfoil and are heavier. In fact I rode with Greg in your machine and it flew very good on a Disk that was 2 feet smaller. To be quite honest had the personalities of Dad and Greg not clashed I would bet think you all would be flying my dad’s blades. I would really appreciate your opinion of how rotor blades fly and the differences between them if you actually flew gyros. I realize your a high time trike pilot bit that does not translate when Evaluating rotor blade performance. I know there was a disagreement because Dad charged you for adapting your rotor head to his blades. For some reason this was perceived as wrong and that Dad should have eaten the cost of this. I don’t think you guys paying for a set of Teeter towers justified being told that he should pay 250.00 an hour to evaluate the blades for your use. I think the major reason for the negative opinion of the new blades was due to a personality clash more than true performance. It’s all water under the bridge now. Just wanted to set a few things straight. I wish you the best with your product.
 
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