OK; so wanted to start a thread on this versus the other forum so I can understand pros and cons of these new carbon fibre blades without folks getting all crazy and personal.

OK, clearly they are much stronger than other blades and will weigh less.
Trying to understand why they are more stable in flight as they are reported to be. Is this by virtue of the carbon fibre material or the hub and blade design.

I understand where strength is important, though is it that significant when blades are spinning and have strength due to centrifugal / centripetal force?

I have been led to understand that heavier blades are more stable and smooth in flight as in the Magni. So is lighter weight not a disadvantage in a rotor?

I understand where strength and light weight are an advantage of carbon fibre in a prop or driven blades like a heli , but not sure where light weight is an advantage in a gyro rotor blade except of course decreased overall aircraft weight.

What happens with a blade strike with these, do they shatter?

Just some questions, no question carbon fibre and titanium make the Tag the sexiest machine yet.

Good thread Loftus... IMO this topic would be an interesting discussion... I think we all may learn from it... THX for starting it!

The little (very little) I know:
*Carbon fiber blades are molded in a process vaguely similar to fiberglass.
*They are lighter.
*They 'can' be stronger, depending on the design and fabrication.

Now here is the theoretical stuff:
It seems to me... since the fiberglass or carbon fiber blade is molded... it 'could' have any 'twist' or profile, over the length of the blade an engineer designed. It seems to me also that this may well be difficult enough in an aluminum blade... that it has not been developed as much as could have been.

SOOOO...

IMO if molded blades (carbon fiber or fiberglass) become the norm in gyro's, and are made by many different shops... IMO sooner or later the engineers are gonna start fiddling with different blade designs and twists... which IMO is bound to improve performance.

Seems with what has been done with molded carbon fiber blades on military helicopters... I suspect there is room for improvement with gyro blades.



Watching to see what folks who know more about blades than I... add to the thread.

Just another light material it's what you do with it and what environment it will be used in, seen it used everywhere ,

carbon fibre is a cancer causing element when fibres are broke loose , when cured handling broken pieces can cut better than a razor blade
heat stress from compressive bending will cause voids and cracking. with other metals is will cause corrosion and needs to have a barrier put in place.

erosion and fod can turn a high buck piece to become scrap, repairs for minor damage can be a pita.

Some cores can entrap moisture another pita.

It's not a cure all or a super tech idea,,,, It has its place.

Why couldn't you build blades from roto-molded polyester plastic, like a kayak? Would still use an aluminum spar?
The only advantage I can see with the carbon fiber would be weight and would have more torsional rigidity on a heavy machine.

It does have its place,I'm not sure gyro blades are it, but I'm willing to keep an open mind.

What I DO think is long past due, especially for your ultra light project Elwood, is carbon fiber tubes filled with expanding foam.
Imagine an ultralight gyro made with carbon fiber tubes mast,and rotorblades! With the weight savings you could easily put on a rotax 582!

My wallet sure would be lighter!!

The carbon blades should have way less droop so machines with clearance issues should become almost immune to slow speed flapping/tail strikes, because they should keep their preset coning angle, even when the rotors are stopped (almost) Having lighter rotors is a bonus to MTOW, the tipweights will ensure plenty of stored energy so it appears to me, that is ++++ so far.....

As to being 'more stable' I think that was a poor choice of words.... maybe more stable when starting them (less likely to flap) but an idiot pilot could still 'hinge them' and slowing them down they might be more stable....

They should be no more stable than any other rotor at flying RPM, it is the benefits I see when they are not at flying speed and where the others loose their rigidity (from centripetal action) the CF rotors will shine.

I would suggest that on a slight scuff on the ground, they should be stronger, however, a full on roll over could be interesting.... but do you want twisted lengths of bent aluminium rotor still encircling you in a tip over, or would you rather they snapped off and flew clear? I have seen people hurt in a roll over from the slowing rotor catching them.... I personally think in a proper ground strike, if the rotors break and vacate the crash scene, less energy will go thru the machine (and pilot) once the CF yields and releases the energy.

I will talk to Sam (the test pilot) and report back to you guys......

Many hours of operation and sadly, one or 2 real rollovers will tell the real story, I don't think they will be any more stable in flight, but in every other aspect, I simply believe they will be better in all other aspects.

Neal doesn't do things by half.... if he chooses them, believe me, they will be great rotors..... time will tell, but I feel extremely confident they will be 'marvelous' (ie phucking great)

I have seen only a couple of pictures of the blades.
First observations. Carbon blades can be balanced much better than metal blades because the weight distribution by placing the metal rods where they need to be instead of where the thickness allows will be a great advantage.
The twist in the blade can be put in a fashion you could never twist a metal blade. NEVER!!!
Double twisted blades will become standard! Mark my words.
The lightness of the blades is not an actual desired side effect.
Heavier blades rule the world.
More inertia equals more better most bestest blades. Period.
If you want light buy a freaking DW.
Hard loading will be evidently more harmonic than metal blades due to root to tip thickness change that can be achieved only in composite.
Metals won't mill uneven skin material.
OK DID I MAKE YOU CHRIS AND FJ YOUR POINT FOR THE FICKERS WHO DON"T KNOW SHIT????

The lightness of the blades helps us with gyrocopters with pissy small MTOW, the tip weights will ensure the light rotors will pack plenty of punch, like a heavy blade.... I can't wait for some feedback on these things

A couple of things about these blades. They wrap the leading edge and seal it this gives more strength. They also will not be prone to splitting if hit by something. The weight is close to an ELA or MTO. The hub design is closer to a Magni.

That is excellent. Wrapped blades are superior to bonded ones.
Reminds me of the latest recall of the R44 blades......
Making blades forever and still haven't figured it all out....
I am glad to hear the wrapping. Metal foil leading edge?

When the blades show up they are sending a cut away sample. I will also have a MTO sample sky wheel sample and a dragon wing sample. They are being made by a helicopter blade company specially for TAG. But the specs are a TAG design. Word is they could be adapted at some time to use on other euro style machines. But that's down the road.

Damn! That root could take a helicopter abuse!

Plastics have a failure mode that has troubled the industry for years, Yield to failure in a crash or overload, the explosive release of stored energy is very high ,try this take a plastic spoon and put it between your fingers and thumb of your left and right hand ( warning you will feel lots of pain)
now bend the spoon to an overload condition till failure. Keep going till you hear a snap and the sting of the energy going into your fingers..

Plastics will never give a warning at overload, just failure ->) snap (<- that's why most structures are over built..

Seen whole structures missing on planes that were plastic,

That is very true. I do however like the comparison of the Astro van regular leaf and the fiberglass leaf spring.
The fiberglass will peel layer by layer before collapsing.
The steel spring just snaps.
As you sad the application is really the name of the game.

They are painted white on the finished product this will help for heat absorption. If I am not mistaken the 787 has carbon wings I flew one to Alaska and was blown away at the flex in that thing

I think Jim Vanek paints his blades for the same reason.
Keeping the blades white reflects the sun back and the heat doesn't mess with the bonding agent.
I think that is a very good practice.

cool that people trying to improve gyro technology you tell the cord is 220mm its 8,661 inch , like hilberg tell its a very good product can be used at many place but have its quirk , i am not a composite guy , but like to reed a little on this product more availlable than in the past for simple people , like muz tell if you crash the blade is scrap like aluminum anyways, the leed rod or metal nose weight can ad some resistance to explosion hit , and depend on the spar composite building technic also with long filament , but for weight and stifness this stuff is hard to beat , if you look at the redbull air-race plane mx mxs its full carbon and is good to 14g its incredibly strong but if you smash it explode in splinter everywhere, for race car like F1 and some top exotic car to avoid the explosion shock when it hard , they combine kevlar in some place, but have a special process called carbotanium http://en.wikipedia.org/wiki/Carbotanium , and i think lamborgini also have his own stuff like small titanium wiremesh like screen imbeded in the woven carbon-fiber tissu , in composite that never end and can cost big $$$ , i reed some where that you have époxy at 50k $ for a 45gallon barrel , ok its not gyro thing but nasa and helico commercial blade like, just some talk , happy for all this new gyro crew , i think that will put a realy good new product on the market

you are correct gab normally black carbon parts with clear époxy is not good Under the sun thats wy only estetical parts is like this and good expensive parts are paint

i see a tv show 2 day ago on a f1 pilot for sauber in finland or sweden i think and he build for the show is brake pedal with prepreg carbon mold and enclave, in a steril room , the small brake pedal cost 15k and this part run fast on road but dont fly at altitude