When should I start worrying about the CG. The turbine is mounted on the Roo. I need to place the ECU, pump, propane system, and batteries. The bat's will be placed for the final CG. Do I start now or wait until after glassing and painting. Im not sure just how much glass and paint effect things. The Roo is notorious for being nose heavy with such a light turbine. I made the fins out of solid balsa to add a bit of weight in the rear. I never use nonfunctional weight for balance. Bkf

Well bkf im no expert on Roo's or anything and i only have 12 flights on mine, but i can tell you were my stuff is located. The engine is a P-80, my ECU is located just about on the Cg on one side and Rx just about the same place only opposite side of the fuselage. The ECU battery is located as far back as it can go (all the way back) as well as both RX batterys.( all the way back) Reference your question about glassing. My wing tip tanks are hollow and very light. If i take the tip tanks off,that effects the CG quite a bit. So i would say that the weight of glassing would effect things allot. Also from past posts about the Roo, it sounds like this set up is the norm. Like you said they do tend to be nose heavy.
Hope everything is coming along great with the rooster. get that baby finished and make some jet noise

Andy

Thanks Andy: I was looking at the picture of your Roo's insides when your post came in. I figured out where the ECU is going. Closer to the receiver than I like but not on top of it though. The propane, solenoids, and pump are going in just in front of the mains. Don't really need to get at that stuff often but if I do I just take the fuel tank out. I should have it done by the weekend then it's glassing time. BTW can you tell me what the dimensions of the UAT are. Thanks Bkf

Im at work right now, but if nobody gets an answer to you by the time i get home ( 2 hours) i will look at mine and measure it. Ya i have my solinoids on the back former just in front of the mains as well. Your right, taking out the tank is the answer to getting at the stuff back there. They say to get the ECU as far away from the RX as you can, but the big thing is of course the range check.

Later

Andy

UAT..... well lets see if i can describe this right. As it sits in my plane, refer to pic on other post.

1 1/2" wide

2 3/8" tall

3 1/4" long

Andy

Thanks Andy. Bkf

Hey bkf here is another pic for your Roo pic web site