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General control line discussion => Open Forum => Topic started by: ron young on July 14, 2012, 05:11:33 PM
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I hope this isnt to long ,a year ago i won a nobler complete with enya and em trying to fly it so today i finally got it to run after several previous tries i did not notice any particular vibration but in one flight muffler was hanging and engine was hanging but didnt loose either and landed in one piece not sure how im going to get the proper screw for the strap type muffler retap and deal with that i guess.But my real delemma is that this plane pulls much harder than anything ive flown i mean to me scary line tension can this be common i adjusted the leadout so that upline is about at the spar because had flown it once before and my buddy said leadouts to far back
nobler( not profile),enya 35v,5225,apc 10/5 prop everything was intact from previous owner(was from estate)
thanks for any thoughts on this matter
Ron
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Check the CG (18%-20% to start should be ok). Hang the plane from the LO's, and eyeball the fuselage or flap hingeline to see what's up with yaw. Move the LO's so there's only a slight nose down while hanging from them. With the engine & muffler coming loose, I'd wonder if that might have caused some of the line tension problem. Gotta fix that, for sure.
I'm not an Enya guy, but I believe Enya, OS and ST all used a 3mm x .6mm pitch thread on the 1960's engines. The easy fix is to use 5-40's. H^^ Steve
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Thanks Steve i connected wire two both lo,s and plane is nose heavy with flaps being level,if i put a 4in level on fuelage and it needs about 5/16 shim to be level not sure im making sense but this is what i did
Ron
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Being nose heavy leads to more line tension. Can't give you the "scientific" reason for it, but it is real. The Enya with a muffler is much heavier than the unmuffled Fox .35 that the Nobler was designed around.
Sounds like you *might* be able to move the lead outs a touch more forward with the nose hanging down like you have done.
BIG Bear
RNMM/AMM
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Hi Ron,
Nose heavy could certainly do it; then again, it might be the model is simply flying too fast. Those Enyas were fairly powerful engines for their time, and have the potential to pull pretty hard depending how you set them up and run them. Can you give us any more info on line length, lap time, fuel and type of run?
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As far as screws for your engine, go to your local Ace Hardware with said engine/muffler. Then go to the nut and bolt section of the store and have fun. That is where I get most of my engine screws/bolts. H^^
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Could be also your still not used to it. Flying something bigger for the first time can be scary.
Is there a way you can measure lap times this will help sort out if your flying it too fast.
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Could be also your still not used to it. Flying something bigger for the first time can be scary.
Is there a way you can measure lap times this will help sort out if your flying it too fast.
This could be correct but i have flown a la46/banshee also my friend elec pathfinder and this plane pulls alot more it is on 62ft lines i am running 15%nitro 50/50 oil mix my problem now is i cut wing tip to install adj.lo and now i have not gained enough if any forward adjustment and the lo is prolly a little short only way i can think of to correct this is to start cutting fuelage aprt actually this seems like it reacts alright im concerned it is pulling so hard it will break the lines under the presure i am quite slow but tonight i will try to find cg at wing tip and advise
Thanks Ron
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Being nose heavy leads to more line tension. Can't give you the "scientific" reason for it, but it is real.
BIG Bear
RNMM/AMM
Hey Bill,
since the model flies or pivots around its centre of gravity in regards to yaw, and is pulling away from you under normal flight conditions, any mass ahead of the CG will pull the nose out.
Add more to that mass and you get more of a yaw, this will induce greater side thrust from the engine.
At least that is how I see it!
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Suppose you have a 42 oz model, with an engine giving 50 oz of thrust. At 50 mph the centripetal force is a bit over 8 lbf. Increase the speed to 60 mph and the pull goes up to nearly 11 lbf. Now, if you yaw the model out a massive 20 degrees, the additional pull due to the outwards component of the thrust will only be about a pound. Which is why a couple of us are wondering about model speed.
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Drop down the nitro to 5%, dump the APC prop for a Master Airscrew or go down to a 10x4. 8)
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Try a flight without the muffler.
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Hey Bill,
since the model flies or pivots around its centre of gravity in regards to yaw, and is pulling away from you under normal flight conditions, any mass ahead of the CG will pull the nose out.
Add more to that mass and you get more of a yaw, this will induce greater side thrust from the engine.
At least that is how I see it!
Thanks, Chris, your explanation makes sense to me!
Bill
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Thanks, Chris, your explanation makes sense to me!
It's exactly right in principle. That's also why you reference leadout sweep to the CG, because technically if you change the CG you should move the leadouts to correspond to it.
The problem is that the effect is very small. Even if you point the engine out 15 degrees, that only gets you about 8-9 ounces more line tension from this effect. This sounds like a lot more than that.
Brett