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General control line discussion => Open Forum => Topic started by: Jim Oliver on October 28, 2006, 08:58:33 PM
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Another "I should know this, but---" question.
Is there some general rule concerning degrees of movement needed for the elevator and flaps on CLPA models? I seem to want more movement than most of the guys I fly with.
Thanks,
Jim
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Hey Jim,
I was told long ago that 2-1(elevator twice the deflection as flaps) was the standard. Everyone probably starts there, but the ratio is subject to change due to power/ weight combos/turning radius and pilots taste/feeling to dial in.Theres probably someone using close to 1-1 throws!
Maybe the Stunt Design forum can put more technical light on the subject for you!
Good luck and catch you in Chat sometimes!
RG
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I have seen the ratio numbers expressed from 1:1, 1:2, etc.
I'm wondering about degrees of movement--I have seen from 20* to 45* mentioned. The kits/ARFs I have don't say even where to start. Most show length of horns, etc. which establishes throw, but I would like to know what is considered to be min and max throws.
Jim
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If you have between 25 and 35 degrees of movement you will be fine. If the truth be know you probably only use 15 degrees in a hard turn. If the plane is balanced right it doesn't take much. Hope this helps.
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It does help--I have been slowly moving CG back on my ARF Cardinal and finding the suggested linkage geometry will work, if as you point out, the CG is right.
Thanks,
Jim
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Hi Jim,
I remember launching a couple practice flights at the '96 NATS for Bob Baron, who won that year with a full size (modified styling) Patternmaster and a ST .60. Bob was by no means a large man, and he was suffering from Leukemia. His handle spacing (between the lines) must have been close to 8"!!!! He needed the leverage to get the turn he desired.
A nose heavy plane does groove and track great, but they can be a *BEAR* to make turn.
10 years ago doesn't seem that long............
Bill <><
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Hi Ty,
I have often been told to not go under the BC size on line spacing by a few guys. I don't know why, but IIRC, there is something to do with the mechanical advantage, etc., that I have never understood in their reasoning. I know the general rule of thumb in the NE is 1" wider line spacing than the size of the BC. ie.: 3" BC, 4" line spacing, etc..
Bill <><
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I think that if you move the handle spacing to far away from the actual bellcrank distance you could get into a situation where #1 there is built in differential in the control. #2 more iimportant, would this not cause a problem with "flying on one line" when the handle is deflected? ie the handle for example , when deflected moves the line attachement one inch but the bellcrank being smaller radius only wants to move 3/4 inch
not sure if this makes sense in words, if not i can try to do a sketch up to illustrate
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Mark,
I remember flying with whatever BC we used in the 1958-1961 time frame with the large EZ Just handles. No particular problems. This was probably like your #2 situation.
Thanks to all for the imput.
Jim
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Jim,
One to one ration works for most models and will be fine on your Cardinal. I flew one in competition last year and used about 3.5" handle spacing. Individual taste vary on handle spacing.
Here is picture of your Cardinal from the Memphis Stunt Classic. Forgot to tell you what a nice job you did with your plane and in the competition. Hope to see you back next year. I really enjoyed talking with you and Lewis.
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Hi Louis,
Thanks for the kind words. Lewis and I had a ball.
My very first CL contest of any kind--I was more than a little afraid of the winds!
As someone once said, "I'll be back".
We hope to go the Rebel Rally. Maybe we will see you there.
Thanks,
Jim
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Jim,
Looks like your initial question has been covered pretty well.
I'd like to add that I build controls so that they are free moving and consistent to way beyond what we need to do the figures. By consistent, I mean that not only at neutral are both flap and elevator at neutral, but they get to the same (or proportional for other than 1:1 angles) extreme throw at the same time.
...and, that they are the same (or proportional) at all positions from neutral to both extremes.
Do I actually get that? Naah, but that's what I try to get ...
A VERY important goal to keep working towards is FREE moving controls - if things go slack on you, you might still get some input through the sagging lines IF they are free moving, but f'r shr NOT if they are stiff or sticky. Free moving does NOT mean with slack or slop, btw.