green river rc

My Feedback: (2)

I have 2 planes that are in need of some adjustments and I'm not sure what to do. The first one is a .35 powered profile Challenger, the wings wobble a bit on the front side of a hard eight, it snaps right out of it on the back side though. My Brodak Nobler on the other hand is just the opposite, it zips right through the front side of a hard 8 and wobbles a bit on the back side. Both ships have flaps and I can't help wondering if it's a coupling alignment problem..what does it sound like to you guys?

Thanks,
David

kdheath

It's a little hard to get used to, but CL stunters also have issues with roll and yaw. Both are undesirable in a stunter, but impossible to completely eliminate. I'm not sure I follow your description entirely, but we can work on it. It sounds like the Challenger is dropping the outboard wingtip on hard inside turns? Accurate? That could be hinging due to excess tip weight. But, that isn't the first thing to do. Here's the link to the PAMPA website and Paul Walker's trimming flow sheet. Have a look at that and we can talk more about it. I'm no expert by any means, but can do the basics and know where to ask for help.
Kelvin

http://www.control-line.org/DesktopD....aspx?tabid=25 (and look under "flying tips" for the trimming chart.)

green river rc

My Feedback: (2)

You are correct about the outboard wing dropping in a hard turn. I didn't get much out of the flow chart, it was pretty vague to me, it just said things like "adjust flaps." That's another thing, the Nobler has all of the links and rods inside the fuse, nothing shows from the outside and nothing is accessible for adjustments. That may be my fault but that is the way it's designed. Both planes are a little fast, I'm going to work on slowing them down and see what that does.

kdheath

OK, that is helpful. I take it it's a kit Nobler? The Top Flite or a Brodak? What's it weigh? What engine and prop does it havet? How long are the lines and what diameter? Does it have a tip weight box and adjustable leadouts? Go over it closely for warps. Be sure the engine is at 0 degrees or a tiny bit out thrust and the rudder straight or right the tiniest bit. Hold it by the spinner and tail post. The outboard wing should drop slowly-a little bit heavier than the inboard.

Generally if you want to slow it down, go to a lower pitch prop-a 4 or 5 pitch and maybe more diameter if the engine will pull it. Or try longer lines. Try for a lap time around 5.0-5.2 seconds per lap. Each extra foot of lines gains you about a tenth of a second.

Fly the ship level upright and inverted. Have someone outside the circle watch the wings and see if it's flying level. If the outboard wingtip is UP upright and inverted, add tip weight. If it hangs DOWN upright and inverted, remove tip weight. If the tip is up one way and down the other, then there is a warp that needs fixing. Or twist the flaps relative to each other (at the flap horn) to get it flying flat. Then we can go after the hinging problem.

That'll get you a long way down the road. Trimming a stunter can take a bit of tweaking and fiddling. In the end it's very much a compromise. And everyone has their own style. But these are pretty accepted basics. Keep us posted.
Kelvin

green river rc

My Feedback: (2)

I have seen the "hinging" word before, what does it mean...hinges on the elevator and flaps? BTW it's a Brodak Nobler.

kdheath

It refers to the plane "hinging" at the point where the lines attach to the leadouts, ie: rolling at the end of the lines, usually dropping an outboard wingtip in hard corners. I agree, it's an odd word, but that's what it refers to.