But does flying that much more nose heavy (205mm to 175mm is a loooong way) make the pattern more difficult? I tried moving my CG fwd (like 10mm) to reduce KE coupling but then holding the elevator on 45s...and point rolling or snapping is now alot more difficult. After praticing P sched with my Temptation (still don't have the integral running) on the weekend I was pretty frustrated. I also found it much easier to flop stall turns with the fwd CG. I really hope the modern planes are more tolerant to the fwd CG.

Colin.

Exactly what are the factory settings for wing & stab incidence? Out of the box mine had the stab at 0 degrees and the wing at -0.3 degrees.

I'm comfortable with the stab, but I have my doubts about the wing. Also, while the stab was aligned with the wing laterally it was 95 deg/ 85 deg with respect to the rudder. Oh, and before I forget, the rudder was twisted as well, about 3 mm from top to bottom.

CG's will vary as to what you like. I only had the prototype flying at 205 and liked it. None of my electrics liked it back there (maybe a glow to electric thing). I like to hold elevator when inverted and I like my snaps to stop when I'm done. Not sure why the trouble with stall turns. You might want to try a different techniques (higher idle, rudder sooner...) and see what works.

Not being a smarta** but stock settings are what I pull out of the box. No one has ever been given the settings, it was just "put wing here and stab here" type thing. I haven't checked one, much less measured one. I know the zero line is the chin crease, but that's all I have ever been able to get. Every Integral of mine has the same program as the one before it, just tweaked to fit the new plane. Nothing drastic between them. I have 1 early one (Nats one) that I need to fix the wing/stab relationship as it's not straight. Usually there's enough stab tube slop to make it perfect if it's not.

The recommended CG is way too far back IMO, I didn't bother to fly the plane with it that far aft as I am sure it would not fly that well.

With the CG at the front of the tube or a little ahead it flies very good, no bad tendancies right out of the box without any adjustments.

From what I have measured the wing/stab are very close to 0-0, or maybe 0 wing and a little + on the stab. I would say what you are seeing is probably right, depends on how accurately you did the measurements. Its tough to set the stab exactly at zero with the fully movable elevator.

I didn't check the other alignments.....the plane flew great out of the box so no need.

I thought 205 was too far back and set mine at 165mm When I built mine.
I have two and both fly about the same with the cg at 165mm. #1 is heavier then the #2 by 10 ozs
To get the cg that far forward I had to add lead to the nose. The second one I built I did not mount the elevator servos in the stab. I mounted a single servo just aft of the fuel tank and made a carbon fiber push rod system. The plane will now balance at 165mm with no added lead.

All pictures are posted near the begining of this thread.

Weights finished ready to fly less fuel
#1 10lbs 12.75oz
#2 10lbs 2.75oz

Carl

I measured mine with a digital level on a granite reference surface. I figure that my measuring setup was accurate to within +/- 0.05 deg. With this setup my stab was 0 degrees, both sides, and the both wings were 0.3 degrees negative.

Before I flew it I removed the wing locating pins with a dremel, and I refixtured both wings to 0.3 degrees positive. With this setup I flew with zero aileron trim, and about three clicks of up trim. I figure that if I had set the wings to 0.5 degrees positive that it wouldn't have required any up trim at all. As it was, the plane flew reasonably well. I mixed a little down elevator with low throttle to get the downlines straight, and I needed a little aileron mixed in with rudder to get it to do a good knife edge.

However, one definite impression that I had was that the plane didn't seem to lock in like other planes that I have had. It was always coming out of my turn-around manouvers on the wrong heading, and I was constantly fighting with the rudder to keep it on track during looping manouvers. After pondering things for a bit, I attributed my problems to the cocked and warped rudder. All in all not a very satisfying experience. However, I'm hoping that Comp-Arf has fixed their fixtures, and the planes that people are buying now are straight, which seems to be the case, listening to all the people on this forum who seem to be happy.

Check lateral cg too. I have a Peso on my right wingtip cause mine wasn't exiting straight either. One guess where I figured this one out

I would be curious as to what the wing and stab are set to in reference to the chin cowl crease line (yellow to purple paint line on the painted ones) now that you've changed it Brenner. If you get some time, would you mind? Thanks

Jason,

My reference was the same line, except further back on the fuselage. Near as I can see it's the same line as the one you're describing, except that it's from white to purple instead of from yellow to purple. The stab is zero to this line, and the wings are 0.3 degrees positive to this line. Out of the box the wings were 0.3 degrees negative to this line.

Also, it's true that measuring the stab is difficult because of the full width elevator. What I did was use the seam on the tip of the stab as reference line and measured to that.

The lateral CG isn't out by very much, but a peso probably doesn't weigh very much either. I'll try adding some wing tip weight to see if it helps.

PS-> They use Pesos in Argentina don't they?

I just checked 2 of the 3 yellow Integrals I have here and the chin line doesn't match the white/purple line.

Yep, Argentina... glad I needed a Coke at the airport...

Yes, it's confusing when you don't know what it should be as a reference.

Jason, is there any way you could ask the guys back at comp-ARF to give us a ruling as to what the stab, the wing, and the motor should all be relative to the thrust line, and also confirm what the thrust line is?

Right now the only thing that I'm reasonably sure of is that the wing should be positive relative to the stab.

They don't know. That's a ZN answer in waiting. Maybe someone with a ZN Integral can tell us what they have?

What I got from ZN was, with the stab at 0 the wing should be a little +

It makes sense, thats pretty much standard.

I added a bit of + to the wing of mine tonight....will hopefully fly tomorrow (weather forecast is iffy) and see how it goes. I double checked knife edge today and I have zero pitch to the belly in both directions. I do have a slight pull to the canopy but not sure what the mix is....I screwed it up in the 14 so only 1 elevator half was moving, so the % I have in there is wrong.....then canopy blew off in the 1-1/4 knife snap (BVM latch pin failed)....so that ended the evening

Thanks Chad. Now fix your canopy so it doesn't blow off. Don't forget the + after Elevator on the mix screen to link the 2 together.

Hi Chad,
Are you able to descibe/picture how you changed the incidence of the main wing. I wouldn't mind slipping it up 0.5 degrees but would love to have the advice of someone who had already done the same thing before attempting this.
All the best, Simon

Chad,

I am really confused. You reduced the downthrust a lot and then increased the wing incidence a little - so the net result is you reduced the downthrust a little apart from the attitude at which the fuz flies which is a cosmetic thing but see below? Now you have increased the incidence a bit more so you are aerodynamically pretty much where you started apart from the fuz angle again. Can you please explain a bit more?

My model balances on the front of the wing tube. It initially carried a lot of left aileron and up trim and went to the canopy on up and downlines. It also needs a lot of rudder/up elevator mixing. At landing speeds it sat tail low making it difficult to judge the descent and set it down smoothly. I checked the wing incidence and found the roots aligned perfectly but that there was a 3/4 deg. difference at the tips so increased incidence on the left panel until they were aligned. It now carries no aileron and less up trim, goes straight up and still pulls slightly to the canopy vertical down. I have this mixed out but the only way I can see to get rid of the mixing is move the CG back which isn't going to help the rudder/elevator mixing. I need to fly it some more but I also think it tends to climb when coming back on the power exiting for example the half outside loop which suggests too much downthrust.

All this says to me that the CG could do with going back but that this wouldn't be good for the rudder/elevator interaction. I appear to have mutually exclusive requirements on incidence and CG and am now at a loss what to do next.

Malcolm

BTW, You owe me a Peso.... I might need it for my Integral!

Verne

Malcolm,

Try this if you haven't already seen it..

http://www.hebertcompetitiondesigns.com/interest.htm

Chris

Chris,

Seen it, want to believe it but like Dick Hanson, until someone can explain to me what's the difference between changing the wing incidence and downthrust I'm not able to!

Malcolm

I do???? It must have slipped my mind...lol. You better not need a Peso for yours or I'd talk to the builder and get your money back

Malcolm,

I cannot explain the trimming to satisfy you unfortunately, but both Nat Penton who is an aero-expert, and Bryan Hebert who needs no introduction more or less agree on this.

Nat will tell you that KE pitch coupling is a function of the thrust-wing incidence separation, his take on it is that they should be less than 1/2 degree separated. Bryan disagree's a bit with this, but by emailing and talking with both of them and apply both their ideas as best I can to my airplanes I am able to eliminate KE pitch coupling. I have done it on my Twisters, and friends Twisters, a friends Dream 110, and my Integral. It takes some patience, and back and forth to get everything right, but well worth the effort. Seriously on the Twister the only mix I was left with was 1% of down elevator with low throttle....and I thought that was not worth the effort to remove!!

I like you, don't like to take things on blind faith....but I figure these guys have much more experience than I do at this so I did this one time and its working for me I can't out smart Nat, nor out design Bryan

On my Twister, I could not get it trimmed in all conditions until I got rid of the downthrust....that was the whole problem with that airplane. Once I did that it was a simple matter of a few small tweaks of wing incidence/CG, and finally stab to get it about as perfect as you could ever hope. The Integral is pretty much going down the same path, and I am sure I will have it nailed shortly, and I can provide some references.

On my Integral it flew off the bench with no aileron trim, so I am surprised that yours needed some, maybe there is some variation in the kits?

* Simon *

I will get some pics later, its not pretty how I did it but hopefully it works.....if my wing panel comes off today then I won't post pics LOL

I didn't believe it either.. Until I tried it.. And as you, I was hesitant to try it.. I learned alot from it..
There are differences in DT and wing incidence IMO.. I learned that from this, and keeping an open mind...But that's not for this thread..

C

I have been wondering the past few flights why its rolling on the downlines and not carrying aileron trim

I am going to suggest Futaba makes that tiny box flash red so I don't forget

I am going to tape my canopy on like Lockhart at the Finals in '06 LOL

Chad,

Thanks for your comments. Like you I bow to both these guys and I don't think what I have observed is very different from what they are saying except in the downthrust/incidence thing. I'm fairly happy that moving my CG forward a bit will bring my setup pretty much to where you are.

As far as my aileron trim situation I know of at least one other Integral here in the UK with a warped panel. Since my incidence mod has removed all the trim I was carrying I'm not inclined to do anything else at this point.

Malcolm

Hi
Jason I notice that you have moved you CG to 175 mm from LE ..... i know this is personal preferences but it seems that i have mine at 195 and alomst same mix but not that much rudder to ail ...and the ke when i have left wing up need more elevator input than the other!
When you have the CG at 175 yoy didnt find the plane a bit jumpy on elevator inverted?