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Discussion Starter · #1 ·
I know if a plane is to tail heavly it can be uncontrollable in flight, But my question is if a plane is pretty nose heavy how will the plane fly?
My guess is that it would just tend to nose down and a bit up elevater would have to be applied to keep it level. Is the guess right at all, is there more to it...?
Thanks for your time, Brian
 

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Nose heavy, depends on how much. Seriously nose heavy planes will not flare on landing, they just start dropping faster and faster as the speed decreases. I have also noticed that seriously nose heavy planes do not turn well at all at lower speeds and can exhibit some very strange high speed snap behaviour.

No new plane should ever be flown without some sort of balance check for sanity's sake.
 

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As Jim said, nose heavy will tend to "fall" out of the sky. It isn't really better to be nose heavy than tail heavy. Landing speeds are higher for a nose heavy, and a dead stick can really ruin the day!
 

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Discussion Starter · #4 ·
Thanks guys! My plane is tail heavy cause of the way it flys and i did'nt know how much weight to put on the front of the plane, because I dont know right were the CG, I know about were it is. The nose goes up and the tail goes down, i cant get it out of a hover! So i put some weights on the front, have not got to fly it yet, i will tell ya how it goes.
Any tips?
Thanks Brian
 

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Yeah, find the main spar in the wing and balance it fairly close to a little behind the spar. On 90% of planes this will put you in the ballpark. I know some 40 size profiles balance up to an inch behind the spar, but somewhere in that range should get you close.
 

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Discussion Starter · #6 ·
My plane balances about 2in. back from the main spar.
Question: When checking balance in inverted flight were should the throttle be at to trim the plane out at first, and were should the throttle be when inverted (?at the same place were its trimmed out at right?).
Thanks Brian
 

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Well, ideally it wouldn't matter where the throttle was as long as it was the same. But that's ideal, and not real life. I set mine at about 2/3 throttle, but that's me and I haven'e even got a reason. The main thing would be to just keep the throttle the same and roll inverted.

Now I don't know this plane at all, but 2" back off the spar sounds real far back.
 

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Discussion Starter · #8 ·
Belive it or not the Power-Line Hobbies Eagle 3-D balances at 2 inches back for the main spar! And to prove it, when i go inverted the plane flyes level.
:)
Brian
 

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Wow, that's way back. But then the spar could be forward too, so really that's a pretty arbitrary way of measuring anyway. The norm would be around 30% MAC but who wants to worry about that?
 

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I move the CG as far back as I can stand it or until the plane flies with no down elevator in inverted flight.

Just my preference.
 

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I get it like Latch likes it, then I add just a touch more tail weight! :lol:
 

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jnjacksn said:
I get it like Latch likes it, then I add just a touch more tail weight! :lol:
Don't let him kid you......His "touch" is a full ounce added at the tail of the plane! :p
 
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