Checked the angle of incidence on stabs and the wings, and the thrust angle, all are zero degree. But did find that the engine's thrust center line is above wing's center line (quite a bit), which can be the root cause of feeling nose heavy. Added two oz of lead up front and it did not help much.

Please let us know if adding washes fix the problem.

I plan on flying mine tomorrow. I just put a Xoar 22X8 on it and losed about 200 RPM. I also added 9 1/4 ounces of lead to the engine box to get it to balance at 6". It should fly very nice now with all of the changes I've made since the last flight.

Need opinions on the cg of this plane:

Acording to the manual it seems nose heavy but the flyght sensation is tail heavy with some belly pitch in KE.

It has a really nice axial displacement, the flying characteristics are really good and IMAC performance is unbelivable.

I did try to center the chaft line near the wing axis but could only lowered 6mm due to the cowling, could this be the reason for the pitching in ke. I also tried putting 1.5 oz in the tail but it has a tendency of gathering altitude at inverted flyight, as I have it now without the 1.5 oz it flies leveled at inverted.

I also moved the tank beneath the wing tube, in the canister tunel thinking how the weight of the fuel afected the pitch in ke but had no possitive result.

I would apreciate any ideas because I am impressed with the performance of this plane and its construction, would love to correct this tendency without mixes.

Is their any out their flying this aircraft with a 3W 56, I have nearly finished building mine and would love to see some photo's with a 3W 56 motor fitted.

Here is one with a 3W 55i. It is in norwegian, but you can look at the pictures

http://forum.modellflynytt.no/showth...ighlight=model

Thanks for the link, but It won't let me look at the photo's until I register, If only I could read Norwegian.

In my experiment with the CG and thrust angle, I found that moving the specified CG (6.5 "behind LE) forward does not help the touching elevator feeling greatly. Rather a negative thrust angle (away from the belly) immediately eliminates the need to use elevators for a sustained level flight. I set mine at 0.3 degree initially.

I did not feel significant difference between before/after adding 2oz of nose weight, and did not plan to add any.

Overall, the Extra 260 flies well, pretty like a pattern plane.

Well, i could help you to register if you want. PM me if you want me to make you an account

I moved the control point further from the elevator surface to get rid of the pitch sensitive issue. If your flies level "hands off" inverted then your CG is dead on.

Thanks for the offer William but I don't need pics that bad, I have just about finished building mine now.If you like I can post some pics of mine here for you all to look at, especially seeing their isn't any fitted with a 3W. I also made a mistake in my previous post, I am using a 3W 55i with a canister.

Pic'c is always fun to watch, so get'em posted
BTW: the plane on the Norwegian forum was also with canister.

Heres a few pics of the engine install. I'm just wainting on the canister to arrive now.

Very nice looking setup!

Did more a couple of test flights during the weekend. It seems the plane likes to fly very fast with Menz 22X8 (DA50, full throttle @7100rpm). It may not be best for IMAC flying. Has anybody tried 23X8 prop on this bird?

I've got a Vess 23A in the wings waiting for me to break my DL-50 in a bit. I had a TBM 22X8 on it spinning 7200 out of the box but went to a Xoar 22X8 after a crack developed in the prop hub. I'll let you know how the Vess works out when I put it on.

Are you guys fitting the top plate the engine box or just leaving it open?

On mine, I covered the top with the center area of the top plate removed. The cut-out leaves about 1/2" of material on each side of the plate. There is not much weight left in the top plate and the box becomes stronger and I can easily access the inside of the engine box.

I left mine off so I could get to everything I stuffed in there. LOL

Here a few more pics, the alloy servo arms and canister muffler arrived today. I will try and get it ready for the weekend now.
I cut the covering from the under side of the aircraft and made up a removeable plate with cooling slots for the canister muffler.
I also need to tidy up my wiring.
What is the best CG to start with on this model

Where did you put your fuel tank?? I have mine just in front of the spar and have balanced the plane with the CG 6" back from the lead edge without fuel. Inverted flight is hands off. This subject does seem to be a matter of huge debate with the guys on this thread so you may want to check with them also instead of just going with my numbers.

I set mine at 6.5" behind LE, with the fuel tank (20oz) located above the deck. I did not feel much tail-heavy or nose heavy. I did adjust the throttle angle to be about 0.4 degree negative.

The 45 degree up line inverted test shows a natural trajectory path.

Yeah, where are you gonna put the fuel tank if you're running a canister? I would assume on top. I put my tank in where the tunnel is and there's not much room left. I set my cg at what they recomended. It flys pretty good to me there. So far your build looks good. Good luck with the maiden.

That would be my next question. My only guess is that the electronics up front are just there temporary for the picture. Otherwise the tank goes in the tail! Good luck on take offs if that's the case! LOL

My tank is going on the top deck just in front of the wing tube between the throttle and choke servo's. I will locate the two fromeco batteries to balance it out. I think I will stick with the manufactures recommendations for the CG and fly the 45 deg up line to check. TIA

That's the same I did but ended up with a 4-cell and a 5-cell in the engine box along with 9 1/4 ounces of lead. This is the strangest plane to balance I've ever owned. Seems like everyone has a different setting and needs different weights. The only variable I can come up with is the tail wheel. Longest moment on the plane and, the only thing that doesn't come with it. Here's the one I used.

http://www2.towerhobbies.com/cgi-bin...?&I=LXBN42&P=0

Pretty heavy.