[Bagger]

I'm having trouble obtaining the correct incidence angle on my QB -3B wings,and request help/guidance from the forum.
I have achieved all preliminary steps ie levels , sweep and triangulation but when setting the block (2.557") on the rear spar and leveling the bubble I find the bottom fairing is bent quite severely down, the rear spar attach is not in line and I have to put a considerable load on the main spar. To re leave all these I find the block would need to be approx 2.25". What are the ramification of this? What do I do? All assistance will be gratefully appreciated. Thank you.

 

[BruceMe]

presumably this is both wings.

90-atan(0.25/36)*180/PI (assumes the main to rear spar distance is 36", I don't have plans so I'm guessing from memory)

If you run that equation, less than half a degree off on incidence. Just align the rear spar/lower skin. It won't impact flight characteristics.

These airplanes fly great, despite all builders best efforts otherwise

-Bruce

 

[acam37]

I had a similar delima with my -4. This is what we did.
http://www.vansairforce.com/community/showthread.php?t=122271&highlight=Wing+incidence
It is now flying and flies perfectly straight. These planes are very forgiving.

 

[Bagger]

Gentlemen, Thank you for your very prompt replies with much appreciated advice.
I have taken all these points in mind and will re-evaluate.
Cheers,
Ian