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tomatocan · 09-13-2009, 12:16 PM

On my larger gas planes I prefer 0 thrust angle, and then I use a throttle to rudder mix to offset any thrust. I began doing this after reading an article by Chip Hyde that extolled the virtues of such trimming. It works better in almost all situations for me. With point mixing, I can have a plane that acts neutrally in virtually every throttle setting. It takes me roughly 10 brief flights and landings to get the mix near perfect.....I then leave it alone while I work on my other trimming. I will usually come back to it after a while and fine tune it a bit more. I have yet to use more than 3% on my gassers.

On my smaller 4 stroke 3d planes, I have been using about two degrees of right thrust , and then finishing out the trim with the throttle to rudder mix. It seems that the torque of the four stroke needs more compensation than I want to use in just the radio. If I try to get it all in the radio, I end up with a mix closer to 12% in areas, which I really don't like.

I have gotten very used to my radio, so I can usually get my plane to about 90% happy in just about ten short flights....this includes a rudder to elevator mix, a rudder to aileron mix, and the thrust mix. It took a lot longer at first. I have been starting with just a linear mix for pitch coupling to get in the ballpark, then after everything else is good, I use a point mix to get it perfect. I have noticed that if I don't take the time right away to do this, it never gets fully done.

I do the cg first, since it will affect the other adjustments... then the thrust, then any pitch or roll coupling.

09-13-2009, 12:16 PM	#7
tomatocan Super Contributer Join Date: Nov 2008 Location: Montrose, CO Age: 41 Posts: 103	Re: rudder or engine thrust On my larger gas planes I prefer 0 thrust angle, and then I use a throttle to rudder mix to offset any thrust. I began doing this after reading an article by Chip Hyde that extolled the virtues of such trimming. It works better in almost all situations for me. With point mixing, I can have a plane that acts neutrally in virtually every throttle setting. It takes me roughly 10 brief flights and landings to get the mix near perfect.....I then leave it alone while I work on my other trimming. I will usually come back to it after a while and fine tune it a bit more. I have yet to use more than 3% on my gassers. On my smaller 4 stroke 3d planes, I have been using about two degrees of right thrust , and then finishing out the trim with the throttle to rudder mix. It seems that the torque of the four stroke needs more compensation than I want to use in just the radio. If I try to get it all in the radio, I end up with a mix closer to 12% in areas, which I really don't like. I have gotten very used to my radio, so I can usually get my plane to about 90% happy in just about ten short flights....this includes a rudder to elevator mix, a rudder to aileron mix, and the thrust mix. It took a lot longer at first. I have been starting with just a linear mix for pitch coupling to get in the ballpark, then after everything else is good, I use a point mix to get it perfect. I have noticed that if I don't take the time right away to do this, it never gets fully done. I do the cg first, since it will affect the other adjustments... then the thrust, then any pitch or roll coupling.