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Old 12-20-2006 | 01:26 PM
  #1  
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From: stanwood, WA
Default Downthrust

I have a mini funtana with the wing in the fwd position, outrunner and a 2100mah lipo. My problem is that when I am flying, everything seems to be trimmed out, But when I Cut back on power The nose comes up. My friend says that it sounds like a Downthrust issue. I appoligize I am pretty new and I am a bit confused about down thrust. It might not be a downthrust issue though, I don't want to add any weight to the nose. Thanks in advance for any advice.
Old 12-20-2006 | 03:55 PM
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From: FL
Default RE: Downthrust

Yes, you may have to much downthrust.
Old 12-21-2006 | 02:22 AM
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From: Chilliwack, BC, CANADA
Default RE: Downthrust

Check the thrust line alightment for up or down angle with reference to the wing.

But it's quite probably that it's nicely 0-0-0 for motor wing and tail. So that leaves you with the idea that you may have your CG a little too far back. Do a search on "dive test" or "dive testing" to find a write up on how to use diving to determine if your CG is on the neutral point or in front or behind it. I'll bet you a bunch of banannas that you've got your CG too far back.
Old 12-25-2006 | 09:44 PM
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From: Bryant Pond, ME
Default RE: Downthrust

In my humble opinion,I think you have to much downthrust. I think the test of that is if when you drop power and it dives you do not have downthrust enough,if on the other hand it wants to climb on powering down you have too much . If the balance is not somewhere right it would fly in hard to handle way [like if the nose is light it would want to stall,if heavy on the nose ,you might not be able to make it stall],depending on how far out it is. I have a full scale pilots license,so I think I might know a little about this subject[no medical anymore though]. Think about it. when you have the downthrust right and it is trimmed right it will not be overly touchy as to power setting . Of course when you cut power it is going to start going down ,law of gravity!
Old 12-25-2006 | 09:48 PM
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From: Bryant Pond, ME
Default RE: Downthrust

Another thought,does this model stall and spin or will it just go into a mush on full up and cutting the power. Some models are made so they don't want to stall and others stall to easy. How does it act this way?

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