Available rotors discussion.

[rwdreams]

Hi everybody. I'm in the market for some rotars. Dragonwings are not available, so I'm looking at my options. Trying to decide if aluminum extruded are a good fit for my dominator single. Option that I know of is :
Sport copter extruded
Tango - extruded
Skywheels, when available- composite
Gyrotech , if available, - composite.

Any thoughts on composite vs aluminum. Any other options. Thank you all in advance.

 

[Kevin_Richey]

Sport Rotors (made by Sport Copter) are not extruded. They are manufactured the same way as Dragon Wings (aluminum construction bonded w/ aerospace adhesives).

 

[Capt'n Gator]

I have the Phoenix Rotorcraft extruded aluminum blades on my Dominator single and I love the way they fly and they are powdercoated white.. Call Anthony Croenlein at 919-340-0038 or 919-569-0038, he is also the distributor for Brako Gyros and they also have very nice rotors.

 

[Vance]

If I owned a Dominator I would do what it takes to find a set of Dragon Wings.

The balance of the machine is set up for the weight of the Dragon Wings and Dragon Wings are lighter than any of the other available rotor blades.

The last set of Dragon Wings I weighed was approximately 49 pounds including hub bar.

A Dominator has a low thrust line in relation to the center of gravity and a nose down pitching when I reduce power and the nose up pitching when I add power.

This is considered a stable response.

Heavier blades will move the center of gravity up and increase the power/pitch coupling.

I prefer the as designed power/pitch coupling.

 

[Brian Jackson]

I believe Averso Stella is another make that Silverlight Aviation is using. Fara (of Silverlight) on the forum would have a great deal of knowledge on this brand. I own a Gyro-Tech carbon fiber rotor though I have not flown it yet so cannot comment.

 

[Kolibri]

Hi rwdreams, welcome here.

The advantages of new 7" Sport Rotors (now with bonded root pad) are many:

greater torsional rigidity (e.g., bonded end caps, vs. screwed in)​

epoxy painted outside and inside (for corrosion resistance)​

automatic internal air pressure equalization​

removable screw in the end caps for borescope inspection​

current aerospace 3M epoxy (vs. DW's no longer used BASF which doesn't well tolerate hot/humid climates)​

hand-startable (Dragon Wings are not), which means great low rrpm recovery in the air​

superior short field takeoff in competition vs. Dragon Wings​

can be pitch tracked (i.e., without using beer can shims)​

superior flying qualities according to many customers who have also flown DW​

better/stronger hub bar and blade straps​

used aerobatically by Jim Vanek​

longest service life in the industry (3000+ hours, on condition)​

renowned Sport Rotor quality​

new production available (Dragon Wings are not)​

Heavier blades will move the center of gravity up and increase the power/pitch coupling.

There is no meaningful weight penalty. 7"x23' Sport Rotors are 67 lbs (including hub bar).
You'd never notice any difference in the power/pitch coupling.

Call Jim Vanek to chat about them:

Welcome to Sportcopter.com

503-543-7000​

Regards,
Kolibri

 

[XXavier]

I believe Averso Stella is another make that Silverlight Aviation is using. Fara (of Silverlight) on the forum would have a great deal of knowledge on this brand. I own a Gyro-Tech carbon fiber rotor though I have not flown it yet so cannot comment.

Yes, Averso Stella supplies excellent blades. I'm using them in my ELA, with very good results.

___________Rotors STELLA___________

Les rotors de la gamme Stella ont étés concus avec un cahier des charges bien déterminé. Efficacité, stabilité, sécurité et absence de vibrations. Pour autogires monoplace ou biplace les diamètres varient de 7.4 à 9 mètres.

www.averso-aviation.com

 

[Abid]

Averso Stella are what we chose for AR-1 and we tested most popular brands. If you are interested in Averso Stella, contact me directly at [email protected] and list your max takeoff weight and engine power for your gyro. Definitely not the cheapest. Extruded Aluminum, been out in the field since 2004 without any cracking or any other major problems

 

[Kolibri]

Of the completely extruded rotor blades, the Averso Stella seem the best.
I've heard good reports about them. The airfoil is NACA 8H12, if I recall correctly.

_____
"Expensive is when the product is not worth the money."

~ President of Leica​

7" Sport Rotors (with hub bar, blades available in 22-25') are $2895.
Jim says that the latest ones with bonded root pad are amazing.
I doubt that any other rotor can beat them for performance, strength, and service life.

rwdreams, I wish you great flying adventures in your gyro!

 

[All_In]

Expect two new manufactures of Dragon Wing type preplacement blades by the end of this year or early 1st quarter.

 

[jrrylee]

Somebody told me awhile back 7" Sport Rotors were extruded, thanks to this thread I learned they are not. Called Jim @ the number Kolibri posted & I should have them in about 1 month. Thanks for the info everyone

 

[Kolibri]

Great, jrrylee, please post on the forum how you like them!

Somebody told me awhile back 7" Sport Rotors were extruded, thanks to this thread I learned they are not.

Correct; while the leading edge piece is extruded out of 6061-T6, the much thinner skins are not (rather, bonded on, with a very tedious and pricey Boeing spec 53-step process). They then peel test a sample from every single set of blades, and archive it. The bond is stronger than the parent material. You won't have to prop up your blades during storage, either. Happy flying!

 

[ToddP]

Expect two new manufactures of Dragon Wing type preplacement blades by the end of this year or early 1st quarter.

Did Ernie sell his blade design?

 

[Alan_Cheatham]

Ernie sold his blade business but it didn't work out so he had it up for sale again recently.
Have a look at these threads:

Dragon Wing Rotors

As most of you know I (Ernie "Boyette) sold the right's to making Dragon wings rotors to a company called Luminati aerospace, which was/is owned by a person named Daniel Preston. The reason for this post into inform all gyro and some helicopter people that this man is NOT to be trusted ! He DOES...

www.rotaryforum.com

For Sale Rotor Flight Dynamics

I am offering Rotor Flight Dynamics inc . for sale including the blade building business Please contact Ernie Boyette at 813 455 9954

www.rotaryforum.com

 

[All_In]

Did Ernie sell his blade design?

Sold it and got it back. He's still trying to sell it.
These are two new to blade manufactures.

 

[C. Beaty]

The NACA 8H12 airfoil was designed in the 1940s as a low drag helicopter rotor airfoil, except things didn’t work out that way.

Laminar flow was mostly a matter of conjecture until low turbulence wind tunnels had been perfected through the use of multiple fine mesh screens to filter out turbulence generated by fans and flow straightening vanes in use up until that time. Laminar flow requires a low turbulence air stream as well as clean, fair surfaces on the airfoil under test.

Anyhow, by the mid to late 1940s, NACA came up a family of laminar flow airfoils that seemed to offer, based on wind tunnel testing, improved performance for helicopter rotors. The 8H12 was the first choice for testing at full scale on a whirl tower.

Alas; the 8H12 did not perform as well as the then standard NACA 0012. This was because the laminar boundary layer on a rotor gets flung off by centrifugal force and the resulting flow becomes turbulent and so was never used for a helicopter.

Designers of hobby copter rotors evidently believe the NACA 8H12 is a special gyroplane airfoil because that’s what Bensen used but he picked the 8H12 for its ease of hand starting. The letter H in the designation stands for helicopter.

The 0012 stalls abruptly which causes hand starting difficulties whereas the 8H12 has a flat stall that makes things easier while hand patting up a rotor.

There are some modern helicopter airfoils that would offer improved performance for a gyro but performance isn’t that important in a hobby-copter.

 

[dinoa]

How much performance improvement would be expected going to say VR7 from 8H12?

 

[C. Beaty]

The drag reduction resulting from a modern airfoil wouldn’t be all that noticeable to the typical the seat of the pants pilot.

A comparison via rotor angle of attack measurement would show a rotor drag reduction of something like going from a L/D 6:1 to 7:1. That’s in the range of L/D measurements that I made a number of years ago comparing a SkyWheels rotor, an excellent example of an 8H12 to a DW rotor.

Other factors, namely misconceptions, enter into seat of the pants comparisons; Skywheels are tail heavy and as a result, pitch noseup when entering an upward gust. This is often misinterpreted as “high lift” but is nothing more than an indication of angle of attack instability. A stable gyro will pitch nosedown in an upward gust, always heading into the relative wind.

 

[rwdreams]

Hi want to thank all of the contributors for excellent information. I have time to consider this, but I'm using a Yamaha, so Vance my balance starts off altered, I'll have to compensate, but that is a great point you make. I will research the weights of all the suggestions. Is there advantages to a heavier rotar, such as energy retention? I am out of Denver so I'm high altitude. I'm sure that should be a consideration. Also while my plans mention 8 inch blades, do most singles now flight 7 inch cord blades ?

 

[Abid]

How much performance improvement would be expected going to say VR7 from 8H12?

Overall about 2 percent on a typical profiled modern gyroplane