I have a Dave Patrick edge with a ZDZ 50 and JR digital servo's all the way around.

I built the plane and flew it and made a few adjustments to the CG and the plane was absolutely awsome i couldnt ask for it to fly any better. It lasted 2 weekends.

Then on the third weekend out with this plane it just went too sh@#. The plane went to flying so bad that it was almost unflyable. I landed the plane and took it home.

I then proceeded to check the plane all over !! I rechecked the CG and found that the CG was a little aft of what i had set it at and the wierd thing was that i have removed 3/4 of an oz. of tail wieght while flight trimming. I rechecked the incidence on the stab and found that it was OK. I checked all glue joints everything that me and a freind could think of to check. We came up with pretty much nothing!!!

I went back out a flew the plane again still the plane is on the ragged edge and fly's bad , meaning that when the throttle is pulled the plane drops the tail. And when flying inverted the plane is in level trim, no elevator input needed at all. It is almost like you cant trim the elevator one pass the plane climbs and the slightest elevator input and plane is climbing or falling there is no inbetween. The plane is just pitchy.
So after this flight test i decieded to try adjusting the stab by adding + incednce to the stab to try and get to the nose of the plane to drop when the throttle is pulled and also to get knife edge to preform correctly , it always pitches to the belly in knife edge so i figured i would fix both worlds by doing this.
Now after i adjusted the stabs the nose does drop when the throttle is pulled but the plane now climbs when rolled inverted! Actually it will do a very steep climb when rolled inverted. However i know that the CG is set forward of the recomended CG range wich is 5" behind the leading edge. Iam at 4 3/4" so i'am pretty nose heavy seeing as how the origianal CG range was set @ 6 inches.

I am at a total loss as to what has happend to this plane. I know it did fly good and now something has changed and it is just not enjoyable to fly or land. Landings are almost a crash every time. It takes all of my piloting skills to land this beast now! It comes in and when it starts slowing down the tail quit flying and if your not quick with the down elevator it will drop the wings and blam it is on the run way without a moments notice!

If anyone can put some input in on this i would greatly appreciate , i can provide pics if anyone wants to see the setup i have and or anything special about the plane.
And also when i read this myself it seems like a CG problem but i have rechecked it and the CG is now at 4" behind the wing's leading edge because i added nose wieght yesterday trying to fix the problem and it does not help.
the plane wieghts in at 15lbs 4 oz. and yes i know this is a little heavy but it did fly good at this wieght for 2 weekend's. [][][][][]

Chad

Ive got the same plane with a zdz 50 ng. what are your low rate elevator setiings? anything more than 12- 15 degrees ( about 3/4-7/8 defelction measured at the front edge of the stab/elevator counterbalance) will be too pitch sensitive for landing. My settings are 15/low-20% expo and 40/high with 70% expo (JR 8103) and I have to be light on the stick when landing. I fly with my c/g @ 4-1/2, I have moved it back several times and it doesn't help the aerobatics but does make the tail drop a bit on landings. There are several posts on here about the c/g and almost all agree that the recommended 6" is too much and 4/34 -5 is the max. At 4-1/2 mine only takes a slight nudge on the stick to maintain inverted, At 5 it would fly inverted with no input on the elevator but felt ---for lack of a better term-----"wallowy" every where else, and like yours seemed "pitchy" Make sure your ailerones aren't "drooped" slightly. That would give you some added lift that you don't need. Make sure that you don't have some funky mixes going on in your radio that might be giving some unwanted surface inputs. Check the centering of your elevator servos. Other than that, i am out of ideas for the moment.
let us know

zonk

Dang,

You have the same exact setup as i do except i have 30% expo in the elevator's and i have 1/2" up and a 1/2" down on low rates. I gues i will move the CG forward a little more to see if that helps!


Thanks !


Chad

It is desirable to find the CG where the plane flies inverted hands off. Remember as you move the CG back the elevators and rudder become more effective. So you will have to decrease the amount of throw all around. Also increase the amount of expo till you get the amount of softness you want in the center. Remember - expo on Futaba softens the center. On Jr/ Airtronics + expo softens the center. Good luck