Originally Posted by
mtnflyer14
I set the CG per Dave's instructions (220-225mm back from wing/fuselage root with gear up) and was able to get it within that range by just moving my batteries around in the forward pockets. I have two 6.6 LiFe batteries for receiver/servos and I think my ECU battery is a 7.4V 3400 MaH battery. I also think I had the UAT full, other tanks empty when setting the CG. In the UF update on CARF's website (that Dave wrote) it has a picture of the approximate CG location. I am not a very experienced jet guy, but the recommended CG seems to work for the kind of flying I'm doing.
Regards,
Gus
I just signed up to RC Universe because of your post. I purchased a UF 3 years ago, I own a lot of H9 & Segual crafts. This is my first jet, I told the man I ordered it from "send me everything needed except kerosene". When I received my UF the manual shows a different wing and the CG showed "360 - 370mm" from the back of the wing (a round tubular piece) forward to the CG. I attempted to make a couple calls (couldn't get response) because the wing shown certainly wasn't what I purchased. Anyway, guessing an approximate CG it ended up that empty of fuel, if I removed the canopy, a balance act starts on its main legs, falling more towards the elevator. I filled it up with fuel and air, put the canopy on and fired it up (P100), I held the brake switch, flipped it to full throttle and nervously let go of the brake switch and let it rip. What a rush. During that flight it took a few up clicks to make it feel familiar, which up clicks to me indicate nose heavy. After my 8 minute timer went off, my nerves then were requiring a respiratory therapist (haha) knowing that around $8000 was going to come down no matter what. I bounced the plane like a super ball and ended up breaking one of the 6mm gear studs. So, using 225mm from the front of the leading edge - I'm right on but as I said, the plane does a balance act when the canopy is removed and because of the front gear spring, seemingly super stiff and without damping, there is hardly any weight on the front gear (meaning, if you get the spring to compress at all - its going to look look like a porpoise) and I find it hard to land without bouncing the front end up and doing a real rookie looking landing. Although no one around here flies so I'm solo and I don't like what it looks like!!
So I am wondering if your UF has commanding weight on the nose wheel or is it feathery weight?
ps, I also have a good method of grinding flats (I read some posts of "impossible") that one day I should picture and share. Also I simply bought a box of 100, 6mm x 40mm dowel pins $45 MSCindustrial.com part 03835675. Hard as diamonds and they to break off just as good as the originals!! I bought these because I didn't know where to shop for new ones.