Harrier wobble?
03-17-2005, 01:50 PM
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Harrier wobble?
I am flying a small Ultimate bipe like the hellraiser. I noticed the inverted Harriers are rock solid but the standard ones wobble a bit. What is this telling me about the balance on the plane?
If I hold it straight vertical by the prop, it seems bottom heavy, but wouldn't that lead to a better standard one and a bad inverted?
Can this be fixed by just making it more tail heavy, or should I add weight to the top of the plane?
Thanks,
Larry
If I hold it straight vertical by the prop, it seems bottom heavy, but wouldn't that lead to a better standard one and a bad inverted?
Can this be fixed by just making it more tail heavy, or should I add weight to the top of the plane?
Thanks,
Larry
03-17-2005, 04:31 PM
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RE: Harrier wobble?
It likely has to do with the height of the CG (not fore-aft placement). Try balancing the plane on it's side, just using a finger or something. See where it balances, and by what you're describing, it'll likely be closer to the upper wing. You could move your gear down on the fuse to help, but I'm no 3D foamy expert or even a beginner, but I think that ought to help.
03-17-2005, 04:39 PM
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RE: Harrier wobble?
The easiest way is to move the battery lower on the fuselage. This will lower the CG on the fuselage. If you hold it out horizontal by the propshaft, does it try to roll over? If so, its top heavy.
03-17-2005, 05:44 PM
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RE: Harrier wobble?
Well my Eflite Ultimate bipe needs the battery just above the fuselage on the center cabane to balance well veritcally. Once I found the right place, and it took a little while, it will harrier very nicely and hover well now. mind you the vertical CG is kinda a compromise with my Ultimate to get better all around performance, but certain things can be improved by changing the balance course then others are worse. Ya just gotta find what you like best.
03-17-2005, 10:02 PM
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RE: Harrier wobble?
Yeah the E-flite ultimate is finicky on CG placement.
One thing I found is that E-flite is extremely conservative on their recommended CG points in the manual. Normally if you move it back about a 1/4"-1/2" beyond what the manual states, it will fly lots better.
The tensor manual states 2 1/4-2 1/2" back from center leading edge. I moved mine back to 3" and it flew even better. It didnt drop the nose on slow speed landings anymore.
One thing I found is that E-flite is extremely conservative on their recommended CG points in the manual. Normally if you move it back about a 1/4"-1/2" beyond what the manual states, it will fly lots better.
The tensor manual states 2 1/4-2 1/2" back from center leading edge. I moved mine back to 3" and it flew even better. It didnt drop the nose on slow speed landings anymore.
