Gyro-tech carbon fiber blades/RAF

Kolibri;n1130039 said:
loops and rolls in Sport Copters: The reason I mention them is not because I think we all should be looping and rolling our gyros,
but because only a robust rotor system will keep us alive over time, especially with hard flying or in vigorous air. Personally, I want a
rotor system that is sufficiently overbuilt that it could often handle loops and rolls.

Jim originally flew Skywheels during his gyrobatics, but they eventually began to crack, so he then started to construct his own.



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Ah, how quickly some forget . . .
Vance, who was it who had RAF control rod ends analyzed by a metallurgical lab to report their low-carbon Grade 0 AISI 1112b material?
Examined personally the wreckage of N5002E that killed Darin Mahler?
Urged (with many photos of my own) the South African RAF owners to carefully inspect RAFSA's hub bar washers for milled flats so that they'd lay flat and not fail the bolt head like the crashed ZU-RHO?
In December I enjoyed a private tour of a factory which makes probably the best replacement helicopter blades in the world (all composite).
Who just last week posted photos of the highly inappropriate hub bar bolts from an Auto-Gyro, which they may still be using?
Was any of that knowable from the internet? I'm out in the real world learning things, and sharing them here.




And I won't pretend that you're correct that I ever made such blanket statements. I haven't.
If you continue to falsely invent words from my keyboard, I'll continue to call you out on it, and you can continue to "
stand corrected" (twice in the past week).
What I have said, and continue to maintain, is that one takes more of a risk with purely extruded T-4 blades vs. something built like Sport Rotors.

I've never accused Averso Stellas of being "dangerous". However they cannot be flown as hard as Sport Rotors, and they cannot last as long.
Any simply extruded T-4 blade will fail before an SC blade does. Thus, they are inherently more risky, which is different from calling them dangerous.
Risk assessments are personal, and every gyro owner must decide on their own level.

Have any Averso Stella rotor systems failed in flight. Apparently not, is the consensus here. Great.
But, let's not imagine that they've the same lifespan as Sport Rotors, or can take Vanek-level flying.




Even for you, Vance, what a baseless and snotty remark.
My documented improvements on my own RAF are testament that I am dedicated to safety, and that my "arrogance" has yet to hurt me.
If anything, I consistently urge of others that they never skimp on quality for their gyro maintenance.
When I upgraded to the SC rotor system, I properly went through the FAA for the Phase 1 fly-off. An arrogant person wouldn't have.


My hope is that you find a different semi-profession before your technical fence-sitting gets somebody hurt.
I cannot recall a single instance where you have insisted on superior quality design, materials, or construction.
Rather, your consistent attitude seems to be "If it's not failing, why kvetch about it?"

You practically assuaged eddie's continued use of $2 crap control rod ends because normal loads won't usually exceed the strength of even the poorest steel.
You expressed no alarm about the Auto-Gyro hub bar bolts improperly having turned down threads within the clamped parts,
and pooh-poohed the importance of bolt grip length. (Even fara agreed with me there.) Chuck Beaty, btw, had a pithy observation about bolts in shear:




In my RAF I'm currently having a new and stronger PRSU mount and horseshoe CNC'ed out of 4130, as the aluminum ones have cracked near the jackshaft.
If I like it, I plan on making them available to others.
When I do, I'm sure you'll have some snide comment about my continued "bashing" of RAF.


In short, Vance, I question your commitment to engineering excellence and quality maintenance in gyros.
You don't take unequivocal stands against lousy parts or design, while berating me for doing so.
You could have at least blandly agreed with me about eddie's control rod ends.
In this regard, I think you set a poor example to your students and the forum's readers.




You made no mention of the hub bar, a component I view as critical.
I believe that Sport Copter currently offers the best. Massively strong, a 7/8th inch NAS bolt, and with an ingenuous lead/lag Heim joint.



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Wrong, eddie. I've never come out against carbon fiber blades. I actually think they're the future for gyros.
I have, however, questioned G-T's relative inexperience with gyro rotors, and especially their hub bar. I still do.
I promote meanwhile Sport Rotors because I've not so far seen anything stronger, safer, or with a longer life. They also perform superbly.




Wow, eddie, "very dangerous" is quite an accusation coming from a guy won't even condescend to replace his RAF OEM crap control rod ends.
Who flew a crack-prone <2004 RAF hub bar for 650+ hours.
Who adds a turbo to a 10" HTL machine and then relies solely on an aftermarket H-stab to handle the increased pitchover forces from 230hp.
Dude, do you really think you can call me "
dangerous"?


Regards, Kolibri

Harder spherical rod ends may not be better because they won't handle being bent as well. That is a part of why AN bolts are softer than SAE grade eight bolts.

If someone knowledgeable was truly seeking answers they would have done failure analysis and destructive testing rather than pretend that they knew how hard they should be.

The spherical rod ends in your RAF when you purchased it would have failed my first preflight as would much of the rest of the aircraft.

A better preflight would go a lot further to enhance safety than pretending to know enough to make judgements about engineering decisions.

As someone who is interested in gyroplane safety; I feel crying wolf about many things that have not failed despite considerable fleet hours detracts from the important things.

I have no way to determine how long rotor blades will last or how they handle aggressive flying without a through engineering analysis. In my opinion; to make claims as though it were fact demonstrates a lack of understanding.

To imagine that Jim is putting higher loads on the blades because of his aerobatic performance denigrates Jim's skill as a pilot.

In my limited experience a properly flown aerobatic maneuver puts fewer loads on the blades then the stabbing at the controls that many new gyroplane pilots regularly do.

I have not been able to exceed 2.1 Gs in any gyroplane doing any maneuver that I attempted.

I don't fly inverted. It is my understanding that a properly executed barrel roll puts no additional loads on the blades. The fact that someone could perform barrel rolls with the very lightly built Bensen rotor system adds credibility to my opinion.

I have no desire to try to teach you anything because instead of listening you argue. I have never won an argument. I have no feeling about you personally. I do find some of the misleading statements you make annoying.
 
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Good article about the rod ends Vance,I am sure it will help people understand that's its the design and and proper preflight that's as important as the part its self.
 
Kolibri;n1130039 said:
Jim originally flew Skywheels during his gyrobatics, but they eventually began to crack, so he then started to construct his own.

I know of at least one set of Skywheels which suffered cracking the first time they triggered an uncommanded mid-air flare at 90 MPH. The pilot recovered and landed safely after the scare. The sudden 90º nose-up was not intentional, just a sudden, divergent instability in the rotor.

The European tests which require testing blades to 3g+ by using the gyro to lift a weighted trailer towed by a truck is a much harsher test. An inside loop doesn't reach 3g, whether initiated by the pilot or by a faulty blade design.
 
Well , ...I've sat on this irritating SLUR ( intentional - or NOT!!!)???? ... for a week trying to decide if it's worth a CORRECTION !

yep in interest of good information ... I WILL wade in ... but in my OWN thread!

very disappointed in Abid .... for resorting to the cheap ..."run down the alternate gyro options - in the minds of prospective buyers" trick! ....... but his "parrot mouth outrunning his good sense " when getting into heated discussions here is well known!:eek::der::wacko::focus:


fara;n1129892 said:
Kolibri: Let me clarify something for you. We manufacture our machines in the US when we can easily go to India or China where we can manufacture the same machine for $15k less per unit at least. Others certainly use this strategy. Titanium with a Chinese factory, AutoGyro with composites from factory in Slovenia in Eastern Europe same one as Trixy gyro uses. My personal commitment to US manufacturing is not just lip service and beat my chest type.
 
GyrOZprey;n1130079 said:
Well , ...I've sat on this irritating SLUR ( intentional - or NOT!!!)???? ... for a week trying to decide if it's worth a CORRECTION !

yep in interest of good information ... I WILL wade in ... but in my OWN thread!

very disappointed in Abid .... for resorting to the cheap ..."run down the alternate gyro options - in the minds of prospective buyers" trick! ....... but his "parrot mouth outrunning his good sense " when getting into heated discussions here is well known!:eek::der::wacko::focus:






Chris sorry you feel that way because it was not intended that way. My own belief about making things in the US does not imply lower quality in ones who don't automatically. I used Sterna prop for a while. Very nice prop. Made in China although Wei is actually bringing manufacturing of it to the US soon. None of this has to do with quality. That is not the context of this statement.
It is however a fact that AutoGyro composite work is largely done in a factory in Slovenia and good work it is and it is also true that TAG composite body and tail and frame are all done in China. There is nothing wrong with TAG machines in quality that I have seen ever. Can't put it more clearly than that.
My commitment is not due to quality but due to my own personal belief and philosophy as an immigrant to this country and nothing more. No one else has to agree with my personal beliefs. I still use Averso rotor from France and still use Rotax engine from Europe. I am not closed off completely to quality just being from here or something
 
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In the early 60's made in Japan was inferred to be low quality,just look at them now nothing but high quality,in a few more years made in china will mean high quality,

I buy USA producst if possible,however the Gyro-tech rotor blades from Poland are of high quality and the price is about 65% less than a similar quality product made

in the USA.
 
I wish all immigrants shared your sentiment about American manufacturing, Abid.
Brian
 
Harder spherical rod ends may not be better because they won't handle being bent as well. That is a part of why AN bolts are softer than SAE grade eight bolts.
Vance, that's true regarding Grade 8 vs. 5, but it's not appropriate regarding Grade 5 vs. 0, which is what I was talking about with Heims vs. RAF OEM rod ends.
Taking your "logic" further, why not make all aircraft hardware out of Grade 0, since according to you such low-carbon steel is still strong enough for normal loads?
This is another example of why I don't believe you have an unequivocal commitment to superior quality.
I think that some of what you say is much more dangerous to the newbie than anything I've ever posted.
You've just sanctioned eddie's continued use of OEM control rod ends, and he even thanked you for it. Swell.



If someone knowledgeable was truly seeking answers they would have done failure analysis and destructive testing rather than pretend that they knew how hard they should be.
Ah, more snotty insinuations, i.e., that I'm not "truly seeking answers" and "pretend[ing]" knowledge. It's actually bordering on hilarious by now.
I actually had RAF rod ends analyzed by a lab, but that wasn't enough for you since I hadn't commissioned failure analysis and destructive testing!
Control rod ends are flight critical parts. The British CAA looked into the crash of an RAF and issued an AD, requiring stronger control rod ends.
The OEM RAF parts have failed often, and in areas other than the push tubes, such as landing gear and alternator mounts.
There's been plenty of failure analysis and destructive testing . . . by unsuspecting RAF owners.

It is hardly "crying wolf" to urge RAF owners to replace OEM control rod ends and <2004 hub bar, if only because even RAF/RAFSA themselves finally admitted the need to do so.



The spherical rod ends in your RAF when you purchased it would have failed my first preflight as would much of the rest of the aircraft.
LOL!!! Of course you would have, because it was my RAF. No scathing from you, however, of the CFI/broker who sold it to me and trained me in it.
Fritts sold an even worse machine to another newbie the same year, and one of its corroded rod ends broke in-flight and killed two people.
You had nothing to say about Fritts then, either, but gave me a lot of crap for my howling about him.

btw, my factory rod ends had only ~330 hours on them, which is less than half of eddie's.
Yet you'd pass a pre-flight of his machine? Cui tacit consentire.
Talk about a double-standard, but that seems typical of you.


________

I feel comfortable flying all of the AutoGyro products.

I know and teach what to look for on pre-flight to recognize when hardware is not working.

I don't see any evidence in your pictures that the hardware was not working.

I have not heard of any hardware failure in AutoGyro products beyond improper assembly techniques by the builders.

I recommend that the users of AutoGyro products not disassemble factory assembled parts in order to inspect the grip length of the hardware.
In my opinion grip length is only important is some specific applications.
OK, Vance, here's a quiz just for you.
Below is that AutoGyro hub bar bolt of previous discussion.
Only ~41% of the lower plate is in contact with the bolt grip. ~59% is not.
You expressed no objections to that.
So, my question to you is: at what lower percentage of contact would you not fly on it? 38%? 35%? 30%? Lower still?


AutoGyro hub bar bolt-3 with 41% grip length.png


_______
Most Euro gyro kit manufacturers proscribe against "excessive" flight maneuvers, such as >40° in pitch or >60° in roll.
Their machines generally are lightly built, and IMO and others, have a somewhat delicate mast/rotor system.

Go take a demonstrator ride in an AutoGyro with a factory rep.
Crank in a hard roll (though <60°) under power and the rep will instantly reduce throttle and chide you.
They know that their machines are "zierlich" (German for fragile, delicate, not sufficiently strong, schmal gebaut, schwächlich ).

For example, AutoGyro Australia issued a
2010 SB about Rotor Blade Cracking:

Problem description & cause of problem
A problem has been found in service on an MTO series aircraft in the UK where, it is believed, high loads have been exerted on the rotor system as a result of manoeuvres considered to be outside handbook limits.

These manoeuvres result in the rotor system having to sustain high G loadings whilst at a rotor rpm less than the design rpm for those conditions. This puts the root of the blade under bending stress, and repeated cycles may cause permanent deformation (i.e. bending) or subsequent cracking of the blade in the area of the outboard bolt hole.

Consideration
AutoGyro Australia has no control over the actual usage of the aircraft, and endeavours to ensure safe flight is maintained. Whilst AutoGyro GmbH and AutoGyro Australia are confident that an MTO aircraft flown within handbook limits is completely safe, AutoGyro Australia require a fleet inspection to prove the safety case in order to allow continued flight operations.

This bulletin requires immediate visual inspection of the rotor blade to hub bar attachment area, and periodic inspection of that area as part of normal 100hr servicing.

It also serves to remind operators that slowing a rotor down deliberately, then quickly exerting high G-loadings (by manoeuvres such as tight turns), will induce significant bending loads on the rotor system, for which it is not designed. Such flight operation invalidates the warranty.

This pdf has exciting photos of such blade cracks:

AutoGyro blade cracking.png



The "significant bending loads" that AutoGyro are so nervous about can be experienced by any pilot
during turbulence, microbursts, or flaring hard from a steep landing descent.
How many cycles will it
take to begin cracking along rotor bolt holes? Apparently not too many, as AutoGyro wants owners to start
inspecting >200 hours and every 100 hours thereafter. (This requires some disassembly, btw, a preflight won't suffice.)

Instead of owning up to design issues, AutoGyro is blaming rotor system part failures on the pilots, just as RAF did in PN39:

Hub Bar Winglets, and AN12 Bolt
Several Hub Bar Winglets have developed cracks due to extenuating circumstances beyond RAF’s control.
Some have questioned the Hub Bar Winglet’s strength. Also during an incident one of the AN12 Bolts suffered
a catastrophic failure at the head. The AN12 Bolt had sustained a number of abnormal stress loads beyond RAF’s control.

Sure, fly your expensive toy like Grandma, and you won't much risk overstressing it.
A Sport Copter, however, you can fly the living sh*t out of. That's a safety margin I like. YMMV.



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Good article about the rod ends Vance,I am sure it will help people understand that's its the design and and proper preflight that's as important as the part its self.
That's some really nice whistling past the RAF graveyard, eddie.
You're relying upon RAF's stellar "design" for their bushel-basket rod end choice?
Have you (as I've urged) even pulled out your old control rod ends to inspect the internal threads for corrosion and cracks?
A mere preflight will not catch a crack already propagating underneath the jam nut, and often not above it.

You know what, forget it, eddie. You are stubbornly blasé about your own life, so I won't bother any further.
Keep flying your overpowered, timed-out, OEM junk-parts-ridden RAF. I hope you won't pay the price for that.
You've been very lucky so far.

Regards, Kolibri
 
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Second I would be dumb to buy my most critical component from a competitor whose business goals are not just the best gyro rotor in the world but direct competition in gyroplane manufacturing with us. Why on Earth would I do that. Why would I place our company's destiny in the hands of a direct competitor. If SC wants to be a rotor system supplier to OEMs they would make rotors and concentrate only on that. Third, SC has not such a great reputation of delivery on time even after being in business for so long, without going into specific examples. That does not bode well for a supply chain partner candidate for us.
Well, here's the "rest of the story":
I asked Sport Copter if they'd ever supplied their rotors to Abid.
They had not. In fact, he requested a free set to test, but they declined.
This begs the obvious question of why Abid asked for a sample if he was never "
dumb to buy my most critical component from a competitor whose . . . "

Since he's had several chances here to tell us straight out that he actually tested on an AR-1 Sport Rotors of __" chord and __' length,
it seems apparent that he never did so. He certainly insinuated that he did (with a wily use of the passive tense, generalizations, etc.).

_______
I don't really care if folks buy Sport Rotors or not. I'm not out any commission, lol.
Maybe their price, or weight, or performance isn't what one wants. It's a free country.

However, I do care if people erroneously claim to have tested them, or falsely accuse of defects or poor quality.

Regards, Kolibri
 
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Kolibri:
The blades that cracked on AutoGyro were due to what I would consider inadequate engineering design. They were a copy of Aircopter rotors and those cracked also. AutoGyro then changed their rotor and changed the hub bar design. They made their hub bar in fact a bit weaker with tapering which would allow it to bend more instead of too strong causing localized stresses in the blades because blades were being asked to flex on the very last hole where the rigid hub bar was ending. Just making a very strong hub bar was the complete opposite to the actual solution and if you design structures that have to flex, you'd know that. This is the same reason why trike wing leading edge tubes have to be sized differently from root to tip allowing proper flexing or you'd have disasters on your hand. The same applies to airplane wing spars whether dual spars or single.

As Xavier Averso said back in 2010 on a RWF thread when this was first discussed here:
"too rigid hub bar for blades not reinforced on the level of the last clamp hole."

The guy did not speak English but he had designed enough structures to understand this basic principle. Whenever you have a rigid member in a structural assembly that all of the sudden ends and the rest of the assembly is a a flexy toothpick, the point where this transition happened is the point where obviously most of the bending will happen in a concentrated fashion and will be a fatigue point. Its best to taper off loads in this transition by making the rigid element less rigid so the flex amplitude is spread over a bigger area. Its simple common sense stuff. There is nothing complicated about it. You are concentrating bending on a small area and it will fatigue way faster and crack. Once AutoGyro realized it and changed their rotor in 2011 and their hub bar I think this has not happened again to the best of my knowledge.
When I saw their hub bar and light blades the first time I think on Roy Hannon's gyroplane while taking a 1 hour lesson from him, I made that comment and I was not even working on gyroplanes at that time. It just seemed wrong engineering to me coming from designing and dealing with wing structures in trikes where flex is the name of the game and in airplane wings like Searey or Legend Super Cub clone. Then Roy did tell me that yes he has to change rotors because there is an AD about cracking on design and new ones were released.

You can also make the hub bar have more pre-cone angle because that will release the bending loads by quite a bit to start with but you pay for that in performance compared to straight hub bar.

Even so, loads within the prescribed limits of non-aerobatic flight would probably not cause such cracks in allocated lifetime but we know people fly these things outside these limits quite a lot.
 
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Kolibri;n1130137 said:
Well, here's the "rest of the story":
I asked Sport Copter if they'd ever supplied their rotors to Abid.
They had not. In fact, he requested a free set to test, but they declined.
This begs the obvious question of why Abid asked for a sample if he was never "
dumb to buy my most critical component from a competitor whose . . . "

Since he's had several chances here to tell us straight out that he actually tested on an AR-1 Sport Rotors of __" chord and __' length,
it seems apparent that he never did so. He certainly insinuated that he did (with a wily use of the passive tense, generalizations, etc.).

_______
I don't really care if folks buy Sport Rotors or not. I'm not out any commission, lol.
Maybe their price, or weight, or performance isn't what one wants. It's a free country.

However, I do care if people erroneously claim to have tested them, or falsely accuse of defects or poor quality.

Regards, Kolibri

I requested a free set of rotors from Sport Copter? When :)? I must be getting old and my memory is not what it used to be but jog it please. The only guy I have ever talked to at Sport Copter was a guy here who used to go by the name of Master Yoda and the only other person I talked to was a lady to order Jim's video which taught me nothing except a glorified advertisement for his products and him doing rolls in the gyro which I had paid $50 for.
I am not saying I didn't ask. It would be great if they did supply rotors to OEMs they want to sell to but I certainly do not remember anything like that. I did not even ask Averso for a free rotor at the start.

Basically I have never talked to Jim in my life and I have talked to MasterYoda just enough that I don't even know his real name. He seemed to be a reasonable guy though.
To answer your question Greg Spicola acted as the project test pilot for AR-1. Though we never directly tested SC rotors on AR-1 prototype, Greg has decent number of hours flying SC rotors on various gyroplanes and his assessment was and is that they are nice but not as good in performance as Averso Stella. We tested Ernie's high inertia blades for a few hours and McCutchen blades for a few days on AR-1 prototype. In Europe I also flew in Girabit rotors and ELA rotors on Apollo gyro. Then later also used Magni rotors as well. In general the attitude of the at the time existing American gyroplane rotor manufacturers we interacted with was lacking professionalism in my opinion compared to the rest of the Light Sport Aircraft industry.
 
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fara, thanks for your replies.

The blades that cracked on AutoGyro were due to what I would consider inadequate engineering design.
Uh, yeah, lol.

So AutoGyro installed a subsequent gen hub bar in 2011?
That also sounds like RAF.

As a keen layman, I generally understand the challenges involved with coning, flexing, etc.
IMO, nobody has spent more time and with greater success solving those challenges than Jim Vanek of Sport Copter.

I think that the Euro gyro companies still have much to learn there.



__________
I requested a free set of rotors from Sport Copter? When :)? I must be getting old and my memory is not what it used to be but jog it please.
Trenna recalled it.

Though we never directly tested SC rotors on AR-1 prototype,
Thank you for finally confirming that.

Greg has decent number of hours flying SC rotors on various gyroplanes and his assessment was and is that they are nice but not as good in performance as Averso Stella.
Too bad that the AR-1 was not used as the test gyro for all different blades, including Sport Rotors.
Then you would have had objective data to share, vs. one pilot's subjective assessment.

You prefer the Stellas. I prefer the Sport Rotors.
Safe flying to us both.

Kolibri
 
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Kolibri;n1130151 said:
fara, thanks for your replies.


Uh, yeah, lol.

So AutoGyro installed a subsequent gen hub bar in 2011?
That also sounds like RAF.

Yes they did put out a new hub bar that had pre-cone angle and tapering towards its ends

As a keen layman, I generally understand the challenges involved with coning, flexing, etc.
IMO, nobody has spent more time and with greater success solving those challenges than Jim Vanek of Sport Copter.

I think that the Euro gyro companies still have much to learn there.

Arrogance is not a virtue and anyone of us can make mistakes. Professionalism is displayed in handling those mistakes and in doing business. Read my impression of American gyroplane industry in general at the time I started. I don't know what I don't know and I can make many mistakes including ones that look stupid but I promise to correct my stupid mistakes when we know and release safety information for our customers to correct them as soon as we humanly can. That's the best we can do. I am sure Jim Vanek of Sport Copter is a very smart and educated guy who will do the same. As I said I have never talked to him.


__________
Trenna recalled it.


Thank you for finally confirming that.

I don't know that name but I do remember vaguely talking to some lady there. I don't have a single email from anyone at Sport Copter or me asking for blades. Usually I do all serious business inquiries in writing so there is a record. Too bad if I asked and she outright refused to supply a test article to a serious startup OEM. May be she did not want their superior blades to go on a competing American product? We have not done too great but we just yesterday received our 30th order in 20 months with a backlog of 8 orders now and we are hiring one more person next week sometime full time.
BTW, I am quite sure Greg's sense about the comparison is on the mark but hey if Trenna ever changes her mind and supplies a test article like McCutchen or Ernie, I can collect the data and post it here for your review for sure. There have been a couple of gyroplanes around here with SC rotors. One is still based at Zephyrhills airport. They are good as I have said. The single seater SC 912 gyro is about the same weight as AR-1 912 plus or minus a few and it seems to carry it fine


Too bad that the AR-1 was not used as the test gyro for all different blades, including Sport Rotors.
Then you would have had objective data to share, vs. one pilot's subjective assessment.

You prefer the Stellas. I prefer the Sport Rotors.
Safe flying to us both.

Kolibri
 
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Not to speak for Jim, but I don't have the impression that he's currently interested in supplying Sport Rotors as OEM to other mfg.
SC already has many orders so far for their upcoming rugged M2, and they are very busy making rotors for their own machines.

His retrofit upgrade offerings (to RAF, AutoGyro, Xenon, etc.) seem done on an individual basis, vs. something he actively seeks out in the market.
If he ever decided that it weren't worth the hassle, I'd completely understand. I'm glad to have had mine since 2015.

For those RAFers not willing to spend the $11,000 on the full SC package (mast plates, rotorhead, air-trim, etc.), I'd just point 'em to Gyro-Tech.
For the $4,200 delivered, it seems at least better than the RAF OEM parts.
I still, however, wouldn't bet the ranch on RAF's torque tube and trim system!

Regards, Kolibri
 
Kolibri;n1130157 said:
Not to speak for Jim, but I don't have the impression that he's currently interested in supplying Sport Rotors as OEM to other mfg.
SC already has many orders so far for their upcoming rugged M2, and they are very busy making rotors for their own machines.

His retrofit upgrade offerings (to RAF, AutoGyro, Xenon, etc.) seem done on an individual basis, vs. something he actively seeks out in the market.
If he ever decided that it weren't worth the hassle, I'd completely understand. I'm glad to have had mine since 2015.

For those RAFers not willing to spend the $11,000 on the full SC package (mast plates, rotorhead, air-trim, etc.), I'd just point 'em to Gyro-Tech.
For the $4,200 delivered, it seems at least better than the RAF OEM parts.
I still, however, wouldn't bet the ranch on RAF's torque tube and trim system!

Regards, Kolibri

I have never sat down and in detail looked at every aspect of a RAF and certainly not a RAF rotor head.
But Kolibri RAF seems to have a fairly well known reputation in gyroplane circles in the US from the past deserved or not. So why would you as a newbie, go and buy a used RAF and then bitch about their quality or safety for months and then spend $11000 on top and probably still not past other issues you listed about fuel tanks etc. Why you as a new person would take a chance with a used machine of a dated design who everyone seems to know has a flawed reputation at least which is quite well known in the USA and which uses an alternative engine as well. I mean that just does not make sense to me. Did you not do any research?
 
Kolibri you have no idea how little I care about your advice,I am glad that you have decided to leave me alone

your raving and ranting was getting very old, so please pack up your dog and pony show and move it on down the road.
 
You just asked Kolibri a very good question,and why would you buy a gyrocoptor that has been in the costal states and subjected to

salt air corrosion for about 13 years and has been poorly taken cared of. Aluminium and salty air just don't mix. My machine is in the

land of very low humidity, and has been extremely well maintained. and your right the RAF reputation is a little on the backside of the

curve. So why would he buy a machine like that,perhaps he is really as clueless as he appears to be. In my opinion his obsession

with safety is just a smoke screen.
 
I think his concerns are from the right place but he does not know as much as he thinks about structure. Just because something is thicker or bigger is not why it is better. Otherwise engineering would be real simple. A great example to learn from is Super Cub, the most well known bushplane in the world. When he cites cracks in AutoGyro rotors and does not realize that the main reason they had cracks is because of their hub bar having two separate beams which make it much more rigid than hub bars that are single bars like a leaf spring in other rotor systems and that is why they had to taper theirs while others can get away with straight leaf springs bending much easier in excess loads when they need to, well that shows what he does and does not understand and for his level that's ok "except" he continues to draw further conclusions and generalizations from that which are simply not right. He even goes as far as saying that because the hub bar of SC rotors is thicker, it must be better without realizing that thicker bar also becomes stiffer and then starts to put more bending loads in hard maneuvers on the blade instead of hub bar and that is precisely what AutoGyro issue was also. The bigger/thicker is always better does not stand in engineering. It is sometimes and it isn't sometimes.

His concern about the hub bar bolts of AutoGyro seems valid if they are really the real bolts AutoGyro uses. I find it hard to believe they are.
 
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Fara about the hubbar bolts, I was thinking the same thing. and your right bigger is usually never better in most aviation applications just heavier.

That's the main reason we have aviation engineers.
 
"except" he continues to draw further conclusions and generalizations from that which are simply not right. He even goes as far as saying that because the hub bar of SC rotors is thicker, it must be better without realizing that thicker bar also becomes stiffer and then starts to put more bending loads in hard maneuvers on the blade instead of hub bar
I never made the blanket statement that "thicker is better" etc. Please stop inferring conclusions I never made.
The reason why the SC hub bar works so well is not solely due to its thickness, but that the rotors are bushed and Heim-jointed
and thus able to find their own coning and lead/lag angles. I've pointed this out several times.



Why you as a new person would take a chance with a used machine of a dated design
Because, fara, even with lots of pre-buy research a newbie wouldn't easily be able to parse out the conflicting camps of opinion.
Chuck Ellsworth vs. Harry S., for example.

Sometimes, one simply has to "go there" in ownership to really learn and understand things.

I recognized then that I was taking somewhat of a risk, but didn't imagine that Dofin Fritts was selling nonairworthy gyros.
I've done what I can to fix mine up, and to warn others about him.
I'm grieved that I didn't know enough in time to have warned Darren Mahler before he bought N5002E.

Does that answer your "question"?



_______
why would you buy a gyrocoptor that has been in the costal states and subjected to
salt air corrosion for about 13 years and has been poorly taken cared of.
Having spent decades near the Gult of Mexico, I'm very aware of corrosion issues there.
My RAF was quite corrosion-free, being sufficiently far from the water and always hangared.

Now, Mahler's N5002E, which had spent its entire time near New Orleans was another story.
Mucho corrosion. Even as a rank gyro/RAF newbie, I would have passed on it.

But, your snarky questions really illuminate more about yourselves than me.
What's worse: newbies ignorantly buying used RAFs with issues, or the CFI/broker who nonetheless sells them?
Go after the Bad Guy for once.


My machine . . . has been extremely well maintained
If it still has the OEM 650+ hour rod ends as your 2017 photos indicate, then your claim is . . . ________.

In my opinion his obsession with safety is just a smoke screen.
In my opinion your lack of obsession with safety seems genuine.

so please pack up your dog and pony show and move it on down the road.

When you meet a master swordsman, show him your sword.
When you meet a man who is not a poet, do not show him your poem
."
~ Lin-Chi​
 
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