I have just finished installing the counter balance upgrade and the LAA measurements will not work as printed. If you lay out the new ribs to the 327.3 the counter balance weights will not clear the lower wingtip and will hang out of the wingtip if you install the weights on the outboard side of the square tube.

The plans don't show this but the fix is either move the ribs 200 mm inboard or making the ribs 90 degrees of the hinge line.

for those of you that have already rivited them as to the drawings you will have to install all but one of your weights inboard and one of the thin weights outboard to keep the tube from crushing.

Have Fun

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Jeff, thanks for the tip. Have you talked with ZAC?
Hi Jeff

Strange I have fitted the counter weights and used the plans and they went fine
You should install the weights on both sides of the square tube in the pic I am resting the weights on the tube to work out the best place for them



If you place the ribs at a 90 degree angle to the hinge as you have done it will work but that isn't what the plans call out. the plans call for it to be angled with the other ribs. Can you post a pic of the tube in the down position?

Jeff, I think you meant Allan. He posted the picture, but I want to thank you for starting the discussion.

I know someone else installed the ribs at the same angle as the other ribs because they were talking about the offset. It looks like the arm in the photo posted will be too close to the wing tip also. Mine looks fine in the middle but then all the way down it is to close to the tip.

I did talk to Roger and he did his at a 90 degree angle off the frwd edge of the skin and that will work but it isn't what the plans show. 327 at the top and 300 at the bottom rivet to rivet will be about 90 degrees but I want the ribs to be at the same angle as the rest so it will look better so I will move it 200 mm inboard and that will fix the problem. So the new measurement will be 127 top and bottom rivet to rivet. I am going to contact Zbag and ask Terry if he can get this changed for us because I don't want to just make changes that aren't approved in writting on others planes.

I have not got one of the down position but I could put my hand flat under the weights with room to spare It is well clear of the wing tip
The ribs are parallel to # 3 rib not the end rib.


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