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Old Nov 12, 2011, 01:33 PM
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Crystal River Fl.
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Hi Dave, No I haven't done anything to the Mig, I just hate the thought of cutting into it, but will have to one day soon. I do have a digital 60 inoz servo to install hoping that that will cure the violent pitch up condition I have. I have flown the Mig twice, it's an awesome plane, fast but oh so cool on a pass down the runway! The flights went great except for the violent pitch up in each flight(for no apparent reason) then I would have to land it, so I could sit down right there and get my heart back under control!!!!! w.
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Old Nov 13, 2011, 05:31 AM
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Chapel Hill, TN USA
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I do think that problem is the lack of the pivot point on the stabs being at 25% MAC. Mine experienced the same pitch up and a 75 oz torque servo doesn't completely cure it. I will have to perform surgery to change mine as well.

J
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Old Nov 14, 2011, 01:01 PM
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Ann Arbor, Michigan, United States
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J is totally right. i messed up my MAC calculation on the flying stab, so the pivot point is set about 1cm aft of where its supposed to be. you can make the simple fix of moving the pivot point 1cm forward on the flying stab with the trade-off of loss of scale position of the flying stab relative to the fuse. i just haven't had enough time to go back and modify the plans. this would entail modifying the flying stab but also the aft planform, the 2 fuse skins and the fin as well. i will get to it at some point, but not the foreseeable future
-beanie
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Old Nov 14, 2011, 03:21 PM
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Crystal River Fl.
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Well, one day when I cut into it, I guess I'll make a couple of new stabs and replace the stabs and the servo... I just hate the thought of cutting into it.. ah well... when I get time.. w.
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Old Nov 14, 2011, 07:53 PM
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Well, judging by the responses, I am guessing that my c.g. was boarder line tail heavy, as that was the only flight that she behaved this way. With well over 200 flights on this air frame, I think it is safe to say that my stab pivot is in the correct location. It seems that there is a very fine line between nose heavy and tail heavy.

Just as a reminder, I included a picture of m actuator mechanism below.
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Old Nov 14, 2011, 10:15 PM
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Ann Arbor, Michigan, United States
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old man, is your pivot point on your mechanism at the original location specified by the plans, or did you move it forward some?
seems that if the pivot point is used as originally specified in the plans, the CG becomes very sensitive, but she'll fly perfectly fine if the CG is in the sweet spot. i suspect that with the modified flying stab pivot point, that the CG will likely become a little more lenient?
-beanie
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Old Nov 15, 2011, 11:22 AM
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correction: the most recent set of plans v2.31 has already been updated to the correct CG and scale positioning of the flying stab. it can be found on the first post. there are a couple versions available, but if you have v2.31, then you should be good to go.
-beanie
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Old Nov 15, 2011, 12:57 PM
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Thanks Beanie! Your plans are great! This is a super plane! Will get to doing the mod one day, busy on other birds at the moment.. w.
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Old Nov 15, 2011, 08:18 PM
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thanks walt! please post pics of you mod when you get around to it.
-beanie
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Old Jun 02, 2013, 11:00 AM
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150 mile house B.C. Canada
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I was just at a mall and first heard then watched 3 of these fly overhead. Very loud and very low, pretty sweet. I had just put my phone away so I didn't get pics or video .
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Old Jun 02, 2013, 11:32 AM
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Quote:
Originally Posted by Wilfor View Post
I was just at a mall and first heard then watched 3 of these fly overhead. Very loud and very low, pretty sweet. I had just put my phone away so I didn't get pics or video .
Very cool! Wish I could have seen the fly over.

I was planning on flying mine today but it is too windy. I can't wait to get back to Texas where you can fly 11 months out of the year.
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Old Jun 02, 2013, 11:51 AM
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A benifit of being in Croatia for holidays. Their military still flys them. I would like to build one of these so posting was an easy way to sub to the thread. Plus bringing back old threads like this is worth it IMO
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Old Apr 28, 2014, 03:18 PM
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help with the parkjet build
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Old Apr 28, 2014, 03:25 PM
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help with the parkjet eurofighter build
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Old Apr 28, 2014, 03:40 PM
Do it Right, the first time!
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United States, MN, Hermantown
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arnold padilla
Two things that will help-- First fill out your profile so everyone knows where you live- USA-what state, city- or what country-at least. It does make a difference!

2 nd, not sure that posting this in the Mig-21 Fishbed thread will help much either. Try the:

Eurofighter Typhoon Park Jet

http://www.rcgroups.com/forums/showt...kjet+eurofight
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