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Why wont my Kaos spin right

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Why wont my Kaos spin right

Old 07-28-2008, 10:51 PM
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DwightMann
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Default Why wont my Kaos spin right

My Kaos spins to the left quite well, but does not want to spin right. I can get 6-8 rotations to the left with the same altitude loss that I get from 1 rotation to the right.

It seems to be trimmed properly, it flies quite well, but takes some effort to make it stall.

OS 61fx 12x6 prop
It starts on the first flip ( why use an electric starter if I don't need to?). I am experimenting with props, can I expect that to help?
Old 07-29-2008, 05:36 AM
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rainedave
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Default RE: Why wont my Kaos spin right

I don't know the cause, but before you go any further make sure your Kaos is balanced laterally (wings stay level when plane is held by spinner and tip of rudder). Then, you might start moving the CG back about 1/8" at a time and see if it improves.

David
Old 07-29-2008, 09:06 AM
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DwightMann
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Default RE: Why wont my Kaos spin right

I have:
Hung by prop and tail
Placed on scale
Flown upright and inverted
Loop

All indicate that the wings are balanced
Old 07-29-2008, 11:54 AM
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crasherboy
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Default RE: Why wont my Kaos spin right

Have you checked the wing for warpage,etc? Ailerons working equal,etc? By that I mean adjusted to the wing the same on both sides?
Old 07-29-2008, 01:10 PM
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iron eagel
 
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Default RE: Why wont my Kaos spin right

Aparently you have checked most of the obvious isssues, have you checked your aileron travel on each side and the stops?
Not having flown a Kaos, or even seen one of late I am not sure how they are set up but that is one thing I would look at.
And it is normal given the rotation of the prop and engine torque that you will get better spin/turns to the left than the right.
Although not knowing you plane I can not say for certain what you are seeing is normal.
Old 07-29-2008, 01:52 PM
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Square Nozzle
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Default RE: Why wont my Kaos spin right

Last time I flew full scale the spin required a full stall and full rudder once the plane stalled. Knowing that I would increase the rudder throw.
Old 07-29-2008, 02:02 PM
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rainedave
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Default RE: Why wont my Kaos spin right

There are several people who fly Kaoi in the Classic Pattern forum. Maybe there's an answer there.

David
Old 07-29-2008, 02:55 PM
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Default RE: Why wont my Kaos spin right

HI,

You didn't say which Kaos you are flying. Sixties or forties. For the .60 engines there is a most noticeable effect caused by engine side (right ) thrust. Note that more power and same side thrust means more tendency to that side. If you underscored the amount as per drawings to the right your plane will be harder to spin to the right than to the left. If you feel your plane have a light tendency to fly to the left that's the point. So I suggest you to check the side thrust angle and correct it as necessary. If you already have everything checked say same amount of ailerons and rudder for both sides, wing is free of warps, no differential travel for ailerons, side thrust etc etc; you can trial increment by 1 degree your engine right thrust . Hope this can help you.

IGOS R/C
Old 07-29-2008, 05:59 PM
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DwightMann
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Default RE: Why wont my Kaos spin right

I do have the same throw in each direction, but since I don't need ailerons to spin left, that shouldn't matter.
This is a "Killer Kaos", I have had others that spun to the right just fine, so I know that the plane "should" be able to do it
Old 07-29-2008, 07:18 PM
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iron eagel
 
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Default RE: Why wont my Kaos spin right

If that is the case that everything as far as the flight surfaces are set up ok, then perhaps the problem is thrust angles. I have found that sometimes "spec" settings for thrust need to be tweaked a bit and that may be an issue. As you have said the lateral balance and CG is checked, and it flies ok for most other aerobatics, so that leaves only other small things that can be an issue.
But the rate of spin is so much different that I wondered about the ailerons interacting somehow. (One a bit skewed at neutral, I had that issue with that once, that is why I asked)
Did you have any trim settings that seemed odd (even minor)?
Have you checked the thrust angles and AOI's?
Is the fuselage straight and true?
I have to admit that it sounds a bit strange that you have such a major difference, without finding any of the control surfaces out of wack, or a warped wing, twist or alike.

If you find an answer to the problem would you post what the cause was?
Old 07-30-2008, 07:44 AM
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da Rock
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Default RE: Why wont my Kaos spin right

Pushrods will bend when pushed, if they aren't sufficiently stiff and/or supported. They can pull without a problem even when insufficiently stiff or supported. So SOMETIMES, a surface will be insufficiently effective one direction, while work the other direction.

There are often many possible reasons for a problem, and the reasons don't have to be directly associated with the problem. For example, this problem would seem to be an aero one, but could be a mechanical one.
Old 07-30-2008, 10:37 AM
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Default RE: Why wont my Kaos spin right

To underline Da Rocks point, I know that the Kaos has very little room between the aileron torque rods and elevator/rudder servo wheels in a traditional configuration. Even though there is no interference felt or heard while testing on the ground there may be a clearance issue that only manifests under the forces incurred during a spin. My kaos had an intermittent clicking noise when throwing the ailerons back and forth until I cut off the excess torque rod length. It's a remote possibility but.........

I also had a mushy rudder when pushed full right though it was rather stiff pulled left. I cut an opening in the bottom of the fuselage where the goldenrod sleeves were attached to the bulkhead and found they had broken away and were absorbing much of the servo travel. I had built the plane per instructions and learned a lot from that little experience. I don't build that way anymore.
Old 07-30-2008, 12:38 PM
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DwightMann
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Default RE: Why wont my Kaos spin right

I have a pull-pull on the rudder, and will double check the elevator.
I know exactally what CrateCruncher means regarding the clearence issues.
Old 07-30-2008, 01:10 PM
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alfredbmor
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Default RE: Why wont my Kaos spin right

I have the TowerHobbies Kaos .40 size powered with a 51 size Super Tigre handling a 12 x 5 wooden prop. I have not the rolling issue since I built it with aileron differential:
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