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Old Apr 07, 2012, 11:52 PM
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United States, TX, Mansfield
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Originally Posted by TwoHeadsBrewing View Post
I just flew my Skywalker this evening and was noticing an interesting behavior: When going from powered flight into a glide, the nose of the aircraft tips up about 30 degrees, almost goes into a stall, then the nose points down and finally levels out.

At first I thought this was a CoG issue, but it balances right at 25mm behind the servo wires. Based on other people's setups, this seems to be pretty close to normal. And the behavior of the plane in general is good and stable.

The other thought I had was that it might be the angle of the motor. If there is too much downthrust with the motor on, when the motor powers off that would cause the nose to go up. It is curious though that the plane doesn't exhibit any dipping down when the throttle is applied.

Sounds to me (and this is a completely off-the-cuff guess) like perhaps your tail (horiz stab) is perhaps VERY VERY SLIGHTLY pointing down (neg. attack)

I would check for that. might not be it, but could be...
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Old Apr 08, 2012, 01:47 AM
Houba ! Houba !!
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United Kingdom, England, Milton Keynes
Joined Sep 2003
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Originally Posted by PMRfly View Post
by the way rcmonster99, thats a funky looking plane on your profile page.. is it a combination of crashed and hanger rashed plane parts?
Nope... It was a scratchbuild creation that came from a confused mind. I cannot find the villages mentioned above either in Nigeria or Botswana in google Earth
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Old Apr 08, 2012, 02:02 AM
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Nope... It was a scratchbuild creation that came from a confused mind. I cannot find the villages mentioned above either in Nigeria or Botswana in google Earth
Lol, yeah they are new towns.. ;-)
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Old Apr 08, 2012, 02:18 AM
OSUFPV - KF7VFT
Corvallis, OR
Joined Apr 2010
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Quote:
Originally Posted by CTvxl View Post
Sounds to me (and this is a completely off-the-cuff guess) like perhaps your tail (horiz stab) is perhaps VERY VERY SLIGHTLY pointing down (neg. attack)

I would check for that. might not be it, but could be...
I think you mean positive AoA. Negative AoA on the stab would mean
when the motor is turned on the added airspeed from the prop wash would
pull the tail down and the nose up. Positive AoA would lead to the nose
pitching down when the motor is turned on, and when turned off, and the
additional airspeed is subtracted, the nose pitches up.

But it's not just the AoA that matters. If you have a lot of up trim this is the
same thing as increasing the AoA and would have the same undesirable
pitching effect during changes of airflow speed. This is the reason why its
important to have a near-perfect CoG to decrease the trims.

Do you have a lot of trim or is your horizontal stab not level?

-Blues
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Old Apr 08, 2012, 06:18 AM
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Joined Aug 2010
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Quote:
Originally Posted by TwoHeadsBrewing View Post
I just flew my Skywalker this evening and was noticing an interesting behavior: When going from powered flight into a glide, the nose of the aircraft tips up about 30 degrees, almost goes into a stall, then the nose points down and finally levels out.

At first I thought this was a CoG issue, but it balances right at 25mm behind the servo wires. Based on other people's setups, this seems to be pretty close to normal. And the behavior of the plane in general is good and stable.

The other thought I had was that it might be the angle of the motor. If there is too much downthrust with the motor on, when the motor powers off that would cause the nose to go up. It is curious though that the plane doesn't exhibit any dipping down when the throttle is applied.
This is a CG issue, move your CG up to about 10mm behind the servo wire channel. Your SW will fly like a glider.
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Old Apr 08, 2012, 09:19 AM
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Canada, NL, Division No. 9
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What is the story on the lowpricerc 168 Skywalker with the "steel" tube in the wing. Has anyone tried this? Is it ridiculously heavy?
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Old Apr 08, 2012, 10:25 AM
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United States, CA, Chico
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Originally Posted by thekubiaks View Post
This is a CG issue, move your CG up to about 10mm behind the servo wire channel. Your SW will fly like a glider.
I'll give this a shot. I just have to figure out how to get the weight forward. As it is right now I have a 4S 5000mah(flight batt) and a 3S 2200(video tx) shoved all the way forward in the nose. Aside from moving the video transmitter, I'm not sure how else to accomplish this balance.
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Old Apr 08, 2012, 11:43 AM
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Originally Posted by TwoHeadsBrewing View Post
I'll give this a shot. I just have to figure out how to get the weight forward. As it is right now I have a 4S 5000mah(flight batt) and a 3S 2200(video tx) shoved all the way forward in the nose. Aside from moving the video transmitter, I'm not sure how else to accomplish this balance.
I have the same two batteries and have the 5000mah all the way forward but the 2200 about half way back. But, I have a 690TVL on the nose and a Go Pro right behind that. I use two canopies, one with Go Pro, and one without. On the canopy without the GoPro, I hot glued in about 6 oz of lead in the hollow underside of the canopy. I can post pictures if you'd like.
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Old Apr 08, 2012, 03:46 PM
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United States, CA, Chico
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Originally Posted by thekubiaks View Post
I have the same two batteries and have the 5000mah all the way forward but the 2200 about half way back. But, I have a 690TVL on the nose and a Go Pro right behind that. I use two canopies, one with Go Pro, and one without. On the canopy without the GoPro, I hot glued in about 6 oz of lead in the hollow underside of the canopy. I can post pictures if you'd like.
OK, I'll give that a shot. I have a Drift HD camera that I've been meaning to test out, so maybe I'll mount that up rather than having just dead weight up there.
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Old Apr 08, 2012, 05:10 PM
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Originally Posted by Grips View Post
What is the story on the lowpricerc 168 Skywalker with the "steel" tube in the wing. Has anyone tried this? Is it ridiculously heavy?
i've had the steel tube version and no it doesnt add unecessary weight, its fine. anything above v3 is fine. infact v3 was good too.
there is a slight misalignment with the wings (1mm) but it makes absolutely no difference to performance and you can barely notice. at 75 clams, its a steal... pardon the pun...
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Old Apr 08, 2012, 05:13 PM
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V4 wing is the best, anyone want to sell me a V4 wing or trade for a V5 wing??
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Old Apr 08, 2012, 05:24 PM
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V4 wing is the best, anyone want to sell me a V4 wing or trade for a V5 wing??
but if u reinforce, it makes no difference?
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Old Apr 08, 2012, 07:59 PM
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but if u reinforce, it makes no difference?
True, I fly mellow FPV cruising so I have never had an issue with wing strength.
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Old Apr 09, 2012, 11:17 AM
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How is everyone attaching the rubber bands on their Skywalker? It doesn't seem like I can get mine on very tight and there is some slight play when I try to move the wing by hand.
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Old Apr 09, 2012, 11:28 AM
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Originally Posted by TwoHeadsBrewing View Post
How is everyone attaching the rubber bands on their Skywalker? It doesn't seem like I can get mine on very tight and there is some slight play when I try to move the wing by hand.
This is how you want to do it.

Skywalker rubber band installation. (1 min 29 sec)
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