Broken ej-22 crank pics

He He Paul, i have never said that a clt gyro wouldnt do the job or wouldnt do the job better and cheaper, i am lookin forward to putting Greg's butterfly through it paces at the Nationals, its just that to this point i am happy with what i have to do the job, that very well may change after the Nationals, and if it does as i have said to Greg i very well may order one while i'm there, the is the beauty and the pain of this style of flying there is so may variables.
I will leave it on this post too so everyone knows who Paul was talking about :))
 
Paul i dont want a sh*t fight either and if it starts i'll just leave it, but can you please explain what you mean by this part of your post?
They have to because most of them run HTLmachines and so have wasted a lot of power to start with!!!!
 
Stan, those Sport copter blades look and sound teriffic but the price for us in Oz is pretty daunting. I read Ken Sandy Ego's results after fitting the SC's and he was wrapped !!
 
Gyromike and Friendly, I will alert Tim as he is the one with the technical info, I'm just a very pleased customer!!
I also hate to see 2.2's getting a bad name just because Raf have some problems in their set up.
 
Mark, my post #18 explains my thoughts on the wasted energy. What I meant was that, a more efficient prop helps to over come the wasted energy from my explanation in post #18.

Clear as mud I think I made it!!!!! LOL

Vance, I still had the same 68" diameter prop as on the Raf. The guys with the 2.63 to 1 reduction of the Rotax gear box run up to 76" props. That is too long for my market, as it makes a machine very high.

Aussie Paul. :)
 
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Makes the machine high Paul but does deliver lots of thrust! :) Also very importantly allows my gyro to cruise along at 3800 revs which gives a fuel consumption of 15.5 liters per hour.
 
Thank you Paul. What is wrong with high? I would think that how it performs would be more important than high? There must be something that I am not understanding. Is it a cultural thing? Thank you, Vance
 
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There's a confusion lurking here between straight-line forces and moments (torques). A straight-line force of a given magnitude will create a torque about any point that isn't right on the line of the force. For a given force, the amount of the torque depends entirely on the how far away from the line the point of interest is. Move this reference point farther away from the line of the frorce and the torque gets larger without any change in the force.

Example #1: Push with 50 lbs. on a 1-foot long torque wrench. You'll apply 50 ft.-lb. to the bolt. Now get a 2-foot torque wrench and push with the same 50 lb. You'll apply 100 ft.-lb. Push with 50 lb. right on the bolt itself, and you'll get 0 ft.-lb., even though you're still applying the same force.

Example #2: Imagine two boys on a seesaw. Say their total weight is 100 lb. If each of them sits out as far out on his side of the board as he can while still balancing the seesaw, how much weight force does the center support feel? Well, 100 lb, plus the weight of the board. If now they both move in to the center of the board, does the down-force on the support change? Nope -- obviously, it's still 100 lb., plus the weight of the board. The kids' weights haven't changed, only the moments that each of them creates by virtue of his location relative to our point of interest.

In a HTL machine, the engine applies X pounds of straight-line force to the frame somewhere above the CG. The machine experiences X pounds of thrust. It also experiences a moment tending to rotate the nose downward. Meanwhile, the rotor applies a straight-line force equalling Y pounds of up-and-back thrust. In the HTL machine, this Y thrust is applied ahead of the CG, creating a nose-up moment as well as straight-line lift. The nose-up moment is NOT created by the rotor's making some "extra" force, it's simply a by-product of the position of the rotor's thrust line. In effect, the moment is "free."

Now put the same rotor and engine on a CLT frame of the same weight. Both the rotor and the engine will generate exactly the same straight-line forces as before (X and Y, respectively). The only difference is that, by virtue of their POSITIONS relative to the CG, these X and Y forces don't create moments as a by-product. We've moved the kids to the center of the board.

In switching to CLT, you may get a bit of reduction of parasite drag because you put the pilot right in front of the engine instead of below it. You've reduced frontal area.

A gyro that achieves pitch stability by countering a high thrust line with a powerful down-loaded HS DOES lose efficiency compared to a CLT machine. In that case, there really IS an extra load in the verticla axis that the rotor must carry, not to mention the drag of the HS itself, which the engine must pull along. IOW, both X and Y go up in this type of setup.
 
Thank you Doug, that helps. It does leave the question about what is wrong with "high" unanswered though. Thank you, Vance
 
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"High" would be fine if the the balancing forces stayed reliably the same.

Carrying on the seesaw analogy, a HTL gyro with no HS is like playing on a seesaw with a kid who jumps off unexpectedly now and then. If you're the kid on the other end, you'll get smacked to the ground hard every time your playmate jumps off.

Rotor thrust is a playmate that jumps off the seesaw in certain flight conditions. Rotor thrust disappears in downdrafts as well as during intentional low-G maneuvers. This kind of unreliable playmate should be kept at the center of the seesaw where he won't upset things when he takes his jump.

IOW, rotor thrust is not a suitable force for centering the pitching moment caused by an off-center prop thrust line. Rotor thrust varies suddenly and dramatically. Every time it diminishes, the prop thrust threatens to flip the machine over in a PPO.

A HS is much more reliable than rotor thrust as a counter to off-center prop thrust. But better still is to have the prop thrust on-center. That way, you don't have to design a fix for your "problem" -- you simply get rid of the problem.
 
Thank you Doug, I don't think that you are speaking of the same "high" as Paul. For Paul it has something to do with "his reacreational Market." Thank you, Vance
 
Ah, ok Vance. I mean physically high in the sense that people cannot get them into their garages etc.

Aussie Paul. :)
 
Doug, thanks for coming to my aid when I could not seem to explain myself in simple understandable terms.

I believe that I have a handle on what it is all about, but sometimes I can't express it in the written word!!!!!

Aussie Paul. :)
 
I am trying to understand, you use a small prop so that people can get it into their garage? How tall is your hybrid? My garage door is just a little over six feet. Thank you, Vance
 
Doug, I have gotten a little lost here!!!!

In a HTL scenario of the thrust line 1' above the COM, a prop thrust of 500lbs, and no
h/stab, what counters/balances the 500 foot lbs of torque that is trying to rotate the nose down?

Aussie Paul. :)
 
Paul first off sorry for some reason when i put that question to you your #18 wasnt on my puter, but i knew that was what you would have been getting at, so here is my next question to you, with a clt gyro is it going to use less energy, with full noise, hanging of the curve, slipping sideways ect, to stay slow enough as to not over run cattle, because i would probably guess that about 50-60% of the time that is how i'm flying and especially finishing off a paddock and close to holding paddocks/yards it is probably closer to 80-90% of the time?
I sure can see that there would be benifits in a gyro that was just used for recreational flying, as i said before so many variables..
 
Vance, I don't use a small prop. I use the correct prop for the gear ratio to get the correct tip speed.

The larger the prop the more difficult it is to achieve CLT without the people having to "climb" up into the machine, aesthetics, the garage problem, height when on a trailer etc. That is where the marketing bit comes in. Safety first, followed by user friendliness and efficiencey juggled to make a "marketable" machine to as many people as possible.

Does that make sense?

Firebird height approx. 8' 2".

Width to the outside of the wheel pants 6' 10". We have to check trailer regs around the world to make sure that there is no problem trailering.

Aussie Paul. :)
 
G'day Mark who said....

G'day Mark who said....

..."with a clt gyro is it going to use less energy," I say yes, but I am sure that Doug will answer that correctly for us. I have specifically asked him for that information in post #35. :confused:

Aussie Paul. :)
 
thank you Paul, it kind of makes sense. Isn't a small prop less efficent? thank you. Vance
 
G'day Brian who said.....

G'day Brian who said.....

.....Makes the machine high Paul but does deliver lots of thrust! Also very importantly allows my gyro to cruise along at 3800 revs which gives a fuel consumption of 15.5 liters per hour.

Ok Brian, that fuel burn is interesting. I carry 2 people, with the gross weights between 1130 lbs and 1200 lbs, and use 19 to 21 liters per hour at engine rpm of approx 4600.

When flying solo my fuel burn is down around the 13 to 15 liters per hour at engine rpm of approx 4200. My LED mixture readout still has it running just a little rich, but I prefer that to blowing the engine. Fuel is cheap really!!!! compared to engine rebuilds!!!!! LOL :D

Yours seems to be thirsty compared to mine. :rolleyes: I believe that you have the Rotax box on the ej-22 with the car ecu?

Just for interest sake, how about a few more details, like rotor dia, empty weight, how skinny you are, fuel capacity, prop specs etc.
How about a pic to post?

Aussie Paul. :)
 
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