danielhv

Well Known Member
Im plumbing the wing... got the top skins clecoed on, and im plumbing it up to matchdrill.... I have a plumb hung on each end of the spar on the bottom side. I have 11/32" from the rear spar to the string on the outboard end, and 13/32" from the rear spar to the string on the inboard end. Is 2/32" acceptable? I have not done anything as far as correcting for twist. These are the numbers "out of the box" so to speak...
 
Fixture Adjustable?

If your wing fixture arms are adjustable a couple of turns on the adjustable arm at one end will zero this out.

Means the difference between zero twist in the wing (the design) and 1/16" twist (what you have now).

Is it a big deal? Maybe not, but at 200 mph any twist is going to result in the airflow acting on the wing in a way that Van didn't intend.

Mike
 
If your wing fixture arms are adjustable a couple of turns on the adjustable arm at one end will zero this out.

Means the difference between zero twist in the wing (the design) and 1/16" twist (what you have now).

Is it a big deal? Maybe not, but at 200 mph any twist is going to result in the airflow acting on the wing in a way that Van didn't intend.

Mike

will do... it IS adjustable... I just didn't know how carried away I needed to get! :)
 
It is 3/32" on the -9

Don't know about the -7 but in the instructions for the -9, it states that 3/32" difference between the ends is acceptable. It is stated to measure it after you cleco the tank on (before drilling, etc.). Sounds like you are good out of the box.:)

Alan
RV-9A Wings
N984AW Reserved
 
Don't forget that the fuel tank skins and the outboard skins are of different thickness. Mine were within 1/32" so I figured "perfect enough". She flies great with no "heavy wing" or any other anomalies. Don't remember who said it, (maybe Jay Pratt; "We're building an airplane, not a watch"!)