How do I mix the pitch coupling out of my twist.
05-16-2006, 11:55 AM
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How do I mix the pitch coupling out of my twist.
So I got my twist back in the air and it's working pretty well, but it seems that this airframe has a lot of pitch coupling with the rudder. If I hit the rudder in the air the nose dives down and I get a little bit of roll as well. I want to start doing some more complex things with it like rolling circles and 4 point rolls and such and I am reading that those things will be very hard to do without mixing the coupling out of the airplane.
So the question is, what do I want to make the control surfaces do? I have a 9cap and know how to program it, I'm just not sure how the control surfaces should move.
I figure once I get some suggestions I'll set it to a switch so I can get it in the air, then flip the switch and try it.
Thanks,
schu
So the question is, what do I want to make the control surfaces do? I have a 9cap and know how to program it, I'm just not sure how the control surfaces should move.
I figure once I get some suggestions I'll set it to a switch so I can get it in the air, then flip the switch and try it.
Thanks,
schu
05-16-2006, 12:28 PM
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RE: How do I mix the pitch coupling out of my twist.
Hey schu,
I'm still new to mixes and such... But the way I have done it is to, put in a mix on the control
surface Rudder to ail. and or elev. opposite of the way the plane couples... In other words say
the plane with rudder use rolls to the Rt. on the rud. to ail. mix add a couple %(start low) Lt.
ail to the mix etc on the other controls...
You do know that the mix is throw and speed sensitive, meaning that when you activate the
switch your planes speed and control throw position needs to be the same as when you set the
mix.... Also if you plane was repaired after a crash.... guess you can use mixes to correct "some"
of it..... But.................. IMO, it would be a lot better to check thrust and incidence of your plane..
I'm still new to mixes and such... But the way I have done it is to, put in a mix on the control
surface Rudder to ail. and or elev. opposite of the way the plane couples... In other words say
the plane with rudder use rolls to the Rt. on the rud. to ail. mix add a couple %(start low) Lt.
ail to the mix etc on the other controls...
You do know that the mix is throw and speed sensitive, meaning that when you activate the
switch your planes speed and control throw position needs to be the same as when you set the
mix.... Also if you plane was repaired after a crash.... guess you can use mixes to correct "some"
of it..... But.................. IMO, it would be a lot better to check thrust and incidence of your plane..
05-16-2006, 01:16 PM
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RE: How do I mix the pitch coupling out of my twist.
The repair isn't the problem, the plane did this before it crashed too.
Anyway I was hoping that someone that had a twist or similar airplane could give me an idea of how much each surface needs to move to get more pure inputs.
schu
Anyway I was hoping that someone that had a twist or similar airplane could give me an idea of how much each surface needs to move to get more pure inputs.
schu
05-17-2006, 03:19 PM
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RE: How do I mix the pitch coupling out of my twist.
Hello schu,
in general it is not possible to give precise mix amounts, since they depend on airplane setup (CG, thrust angles, incidences, ...). This is a trial and error process: try with small amount, say 5%, fly, land, adjust, fly, ... till you have a good mix.
One suggestion: the airplane setup for aerobatic flying is more than mixes, and in particular there are some settings that must be addressed before, if you want to have a good airplane: the most important ones are CG and thrust angles. If you have thrust or CG out of range, you will have a plane that does not fly correctly, so it is better to fix those things first instead of using the mixes, which cannot remove all the airplane bad behaviours.
Good flying!
in general it is not possible to give precise mix amounts, since they depend on airplane setup (CG, thrust angles, incidences, ...). This is a trial and error process: try with small amount, say 5%, fly, land, adjust, fly, ... till you have a good mix.
One suggestion: the airplane setup for aerobatic flying is more than mixes, and in particular there are some settings that must be addressed before, if you want to have a good airplane: the most important ones are CG and thrust angles. If you have thrust or CG out of range, you will have a plane that does not fly correctly, so it is better to fix those things first instead of using the mixes, which cannot remove all the airplane bad behaviours.
Good flying!
