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Twist 60 knife edge?

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Old 09-09-2012, 06:24 AM
  #1
stevegauth30
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Default Twist 60 knife edge?

I recently maidened my twist 60, and after adding some lead to the tail and getting it balanced as best I can, it flies nice and level either upright or inverted, but really hard to knife edge. I have planes with much less 3d Capability that will knife edge a lot better. Does any one else notice that, or is it my set up is off? Other than that no complaints.great flying plane.
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Old 09-09-2012, 08:07 AM
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Default RE: Twist 60 knife edge?

What exactly does it do when you try knife?
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Old 09-09-2012, 08:16 AM
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Default RE: Twist 60 knife edge?

Now I'm pretty new to 3D flying, but I have been flying for a few years. I have an edge 540 that will knife for ever. It just won't hold it. It either wants to roll, or turn, or something. It's probably a mixture of my lack of skill, and  a new plane. Does  it have anything. To do with the over size wing? Man that thing is big. My expo is set at  65 and every thing else is good.
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Old 09-09-2012, 11:49 AM
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Default RE: Twist 60 knife edge?

It sounds like you have some control cross coupling. Most of this is design but is also influenced by CG. What most aerobatic airplanes do is when rudder is applied you will also get a pitch change. My guess is that it is pitching towards the landing gear. Moving the CG forward will help that situation. You can employ a mix to fine tune. The roll couple is a dihedral thing. Other then changing the dihedral this can be delt with using a mix as well.

All this is dependant on the fact that the airplane is built strait in the first place. Make sure the wing and stab are level.
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Old 09-09-2012, 12:22 PM
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Default RE: Twist 60 knife edge?

Yeah, I've been moving the CG back and forth all day and trying different things I got it a little better. I can at least knife it now. Pretty sloppy though. I read a couple of other reviews where people say the same thing. What kind of mixing are you talking about? Like adding up or down elevator with rudder?
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Old 09-09-2012, 12:37 PM
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Default RE: Twist 60 knife edge?

Steve, I don't know what TX you have but if it is capable you can set up a mix that will add up elevator with the application of rudder. Almost all of my aerobatic airplanes have required me to do this. It souldn't take much, maybe 1/16 to 3/32 inch mix at full rudder. As you have observed, moving the CG forward will help.
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Old 09-09-2012, 12:54 PM
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Default RE: Twist 60 knife edge?

Yeah, I have a DX8 and I've already been doing that for all of my warbirds seeing that they almost all sink like a rock once you slow one wing down. I already have some mixed in there, but I'll add a bit more and see how that works out. Thanks a lot for taking the time to answer my questions.
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Old 09-10-2012, 06:31 AM
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Default RE: Twist 60 knife edge?

The Twist airframes are not good at knife edge. The tail is too short. An increase in rudder size will help, but KE is just not a Twist strong suit. I know someone is going to tell me I am wrong and their Twist will KE all day long. Good for you, but I stand by the above.

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Old 09-10-2012, 06:57 AM
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Default RE: Twist 60 knife edge?

You are right David. I have a Twist 40, and it will knife edge, but not very well. I always wants to squirm out of KE. I can fly it constantly and hold it in, but it is a lot of work. I thought it was just me, but all of my other planes (except speed planes) knife edge pretty well.

They spin really good though.
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Old 09-11-2012, 11:36 PM
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Default RE: Twist 60 knife edge?

Yes the twist is a hard plane to KE BUT KE a twist will only make you better at KE.
After learning to KE my twist I can really KE some of my other planes.
The twist taught me how to flat spin as well as hovering
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Old 09-12-2012, 08:39 AM
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Default RE: Twist 60 knife edge?

With the Twist you'll need some mixing.

Set about 8% rudder to elevator mixing so that pushing the rudder left or right from level flight at high to full throttle, results in NO nose drop. Remember to adjust the "curve" so that pushing in BOTH directions results in the elevator moving up a bit.

With hard rudder at level flight the plane will seem to yaw around a point, but will eventually want to roll or decend as it looses speed thanks to the hard yaw.

Adjust the mix as needed to attain this, and preferably set the mix so that you can flip it on with a switch.

This will help knife edges GREATLY as well as other manouvers.

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Old 09-30-2012, 01:12 PM
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Default RE: Twist 60 knife edge?

Yea it take some mixing to KE a twist. It's like an ultra stick that it take most of the rudder some aileron. And elevator to do it.
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Old 09-30-2012, 10:06 PM
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Default RE: Twist 60 knife edge?

My teist 60 is a knife edge dog. I hate this plane.

It's more funflyer. Knife edge charactersitics are hard to read because it will snap to canopy or wheels via lottery. It will roll out or fallout. 
The only things it does well involves post stall.
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Old 10-01-2012, 12:14 AM
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Default RE: Twist 60 knife edge?

Yeah, your right Tim. It is a lottery. Some times it pulls to the gear, and some times to the canopy. You can't set the balance one way or the other. It's a fun pland, but not my idea of 3d. For 3d, I like the edge 540 . Thanks for your input.i didn't know if it was all of them, or just mine.
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Old 10-01-2012, 08:06 AM
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Default RE: Twist 60 knife edge?

You should really try setting up the mix as I indicated.

It WILL cure knife-edge troubles.

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Old 10-01-2012, 01:45 PM
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Default RE: Twist 60 knife edge?

I'm working on the mixes it more hard work than its worth. My GW EDGE does better 3D flying.
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Old 10-02-2012, 07:00 AM
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Default RE: Twist 60 knife edge?

Yes Like I said the better you become KE the twist the far better you are at KE your 3D birds. The Twist is a funfly airplane and requires far more skill for 3D.
It's more of an everyday bang around, fly in the wind type of plane.
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Old 10-02-2012, 08:34 AM
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Default RE: Twist 60 knife edge?


Quote:
ORIGINAL: TimBle

I'm working on the mixes it more hard work than its worth. My GW EDGE does better 3D flying.
It's quite easy to set up.

Create a rudder to elevator mix.

The default will cause the elevator to move up at one extreme of the rudder and down at the other extreme.

Look for the point on the curve where the elevator moves down and invert that...

e.g. if it is at -100, change it to +100.

Once you get the elevator moving up when you move the rudder in either direction, tone down the amount. You only want about 6-8% instead of the default 100%.

Put this on a switch so you can turn it on or off for testing. Once you have the correct percentage values, you'll want to leave it on all the time.

With the mix in place the Twist Knife Edges VERY well. If you are using a larger prop a rudder to aileron mix may also be in order but that is non-symetric.

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Old 10-02-2012, 10:09 AM
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Default RE: Twist 60 knife edge?

I don't think you get it.

I know how to program the mix. The point is the plane does not respond in a consistent manner to the mix. It requires constant correction and is extremely sensitive to even the smallest over correction.


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Old 11-08-2012, 01:12 PM
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Default RE: Twist 60 knife edge?

I agree it plain flys like crap in certain aspects. It is a beater plane. Does good at certain things and is good windy day plane that you dont have too much money to loose, but I woulndt waste a lot of time trying to make it perfect KE it just is not good at that. Mine is unpredictable and erratic too, mix doesnt fix that. You can fight the Twist, or just by a Funtana and smile all day long.
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