[KC8QVO]

I took my GP FlatOut extra 300s out the other day twice. There was a tad bit of a breeze, but nothing the airplane couldnt handle (its been in MUCH worse ). It seems to be real twitchy. If you let go of the controls the airplane does some weird stuff. Once you get it all trimmed up it decides to go out of trim. I am constantly on the controls to keep it strait. It does smoothe rolls and loops, but just normal flying around seems difficult. I have added 6 pennies on the tail - right under the elevator at the fuselage - to get it balanced. I am running a 3 cell 860mAh Li-Po, which is mounted right about at the C.G.

Could the twitchyness be caused by too much weight? I do not have a scale so I cant weigh it.

Other than the twitchyness, its a blast to fly. It really builds your confidence.

Steve

[NorseHammer]

What is the balance point you are trying to achieve as measured from the leading edge of the wing at the fuselage? It sound like you have a Tailheavy plane, six pennies is a whole lot of mass to have to add that far back. None of my shockies needed any mass behind the CofG so you've got me wondering.

Norse.

[KC8QVO]

Well... the C.G. is where the book says, about 2-1/8" behind the leading edge at the fuselage. I marked it with pen so I knew where it was. I had 4 pennies back there before but it was even more unstable. When I cut the throttle the airplane would always nosedive, and full up elevator wouldnt get it back on track. Thats why I added the other two pennies. It still nosedives when you cut the throttle, but I can control it now.

Steve

[NorseHammer]

Hmm this is weird all right, mine I've always got to balance simply by placing the components to the best advantage, even if it meant cutting things a little to get them to fit where needed or going to a slightly larger battery if its tail heavy. Does the propellor thrust line look like it's right according to the instructions, does the weight of the pennies cause the tail to flex more? Does anyone else have any ideas? Maybe if we could see a set of "Three View" pictures of your plane it would lead someone to give you another possible solution. These planes arent normally in need of tail weights and usually fly like they're on rails when balanced on the CofG, till you over power them that is.