RCU Forums - View Single Post - Carl Goldberg Ultimate 10-300 Brotherhood.
Old 05-25-2019, 08:43 PM
J.Paul Saure
Join Date: Sep 2002
Location: Concepcion, CHILE
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Originally Posted by warbird_1 View Post

just finished my 30 year old kit. fitted it with a rimfire .80 using a 6s 4500 pack . almost unlimited vertical . CG at the mid point and i have to tim up elevator for level flight. i'm thinking i'm to nose heavy . i am at the mid point on the CG and thoughts?
Hi there!
I just re-maidened my Ultimate today. I changed elevator servos (S9001) to the tail and removed the heavy pushrods. I also went with the "hot dog" throws from the manual, WOW.
I kept the 77grams of lead I installed inside the tail, Saito 125 in the nose. AND I BUILT IT LIGHT.
I think I could go even with more tail weight, but enough for now. At this point it removed some of the up trim elevator, but not all of it. I aligned wings and tail with the incidence meter when I built it, so it's the CG.

I don't remember my exact CG with both wings attached… …last times I just measured a "relative" CG with ONLY THE BOTTOM WING ATTACHED.
My CG was at 90mm from the bottom wing leading edge, ONLY WITH THE BOTTOM WING ATTACHED.
Now it went back to 96mm from the bottom wing leading edge, ONLY WITH THE BOTTOM WING ATTACHED.

PS with the "hot dog" throws I could do a flat spin and knife edge loops.
But I couldn't get it to lomcevak. I'm using an APC 15x8 with the Saito 125. Maybe with the APX 16x6 it could do it….!!!

PS2 I'm also flying it with JETI now!!!! Great choice!

Last edited by J.Paul Saure; 05-25-2019 at 08:45 PM.