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  #31  
Old 09-11-2017, 01:10 PM
David-aviator David-aviator is offline
 
Join Date: Feb 2005
Location: Chesterfield, Missouri
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I used wide jaw vice grip with duct tape over jaws, try gentle squeeze between outboard 2 ribs first.

FWIW, aileron trailing edge was per the plan, now just tiny bit tighter.
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Last edited by David-aviator : 09-11-2017 at 01:14 PM.
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  #32  
Old 09-11-2017, 01:22 PM
jklusman jklusman is offline
 
Join Date: Feb 2013
Location: Lafayette, IN
Posts: 7
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The aircraft tended to roll to the left, so I put the straw under the right aileron.
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  #33  
Old 09-12-2017, 12:19 PM
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flyenforfun flyenforfun is offline
 
Join Date: Aug 2009
Location: Wilmington DE
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Quote:
Originally Posted by flyenforfun View Post
Perplexing heavy left wing problems.
I finished my -8 back in 2012 and on the initial flights we had a heavy the left-wing. We tried everything that vans told us to do and more ideas from vans Air Force forum. Nothing seems to work except re-drilling and lowering the left aileron out board hinge however that caused us to have a heavy right wing but with almost full left aileron trim it flew straight and level so I've lived with that band-Aid fix for about five years. Now I have decided to revisit the problem and try to fix it properly. This weekend I raised the left hinge 1/16 of an inch hoping that I would be able to trim the plane closer to neutral position. So what's happening now is with the trim in neutral position the faster I go the more the plane wants to roll to the left and the slower I go the more it wants the rollback to the right The strange thing is that if you hold the stick in level flight both Ailerons are in line with the wingtips and flaps which makes me think that there is some kind of airflow issue going on that I can't see. I've tried all of the standard fixes like rigging, squeezing trailing edges, trim tabs and even built a brand new right the Aileron i've had various results but no eureka moments. I feel like I'm missing something and not looking at the right thing. Any ideas? I would love to find the smoking gun. I believe everything is set right i.e. Rigging, wing incidence, wheel pants and fairings. Somehow somewhere I am inducing drag and the drag increases as speed increases and vice a versa. Maybe someone on this forum can think outside the box and give me an idea of where else to look.
Thanks.
I have an update to my heavy wings story . I took the trim springs out then flew the plane and I found that as I'm picking up speed the right wing is heavy and is soon as I had 120 kn it shifts to the left wing being heavy. I would like to truly solve this mystery.
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  #34  
Old 09-12-2017, 01:25 PM
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flyenforfun flyenforfun is offline
 
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Location: Wilmington DE
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Quote:
Originally Posted by David-aviator View Post
Matt, have tried very gentle squeeze of right aileron?
I built a built a new right aileron and no change
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  #35  
Old 09-13-2017, 07:51 AM
Vic LaRocca Vic LaRocca is offline
 
Join Date: Feb 2005
Location: San Antonio, TX
Posts: 45
Default Wheel pants / gear leg fairings?

Have you tested with out wheel pants and gear leg fairings?
- Vic
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  #36  
Old 09-13-2017, 10:29 AM
Vic LaRocca Vic LaRocca is offline
 
Join Date: Feb 2005
Location: San Antonio, TX
Posts: 45
Default Aileron boot?

New thought. Do you use boots on your aileron push pull tubes? If so is one leaking air?
-Vic
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  #37  
Old 09-13-2017, 01:22 PM
David-aviator David-aviator is offline
 
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Location: Chesterfield, Missouri
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Quote:
Originally Posted by flyenforfun View Post
I have an update to my heavy wings story . I took the trim springs out then flew the plane and I found that as I'm picking up speed the right wing is heavy and is soon as I had 120 kn it shifts to the left wing being heavy. I would like to truly solve this mystery.
Matt, as little as 3 gallons of fuel will affect wings level in calm air, ball centered. I proved it starting with full tanks.
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  #38  
Old 09-13-2017, 01:51 PM
ALagonia ALagonia is offline
 
Join Date: Jul 2017
Posts: 64
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My two cents. If that Dynon pitot is larger than the normal pitot and is installed ahead of an aileron I believe that Would create a problem with air flow over/under the aileron. And it's interaction would change with speed.
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  #39  
Old 09-13-2017, 01:59 PM
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Bruce Bruce is offline
 
Join Date: Feb 2006
Location: ADDISON,TX
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Matt,
It's not the aileron.
Your left flap is low.
Induced drag at high speed.

Level plane and measure full length of
Flap from out to in on right and then do the left.

After that rerig ailerons


Hopes its the smoker you are looking for.

Boomer
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  #40  
Old 02-12-2018, 11:12 AM
N999BT N999BT is offline
 
Join Date: May 2005
Posts: 196
Default Solved!!!

To recap, I had a situation that the airplane rolls left at low speed, and rolls more and more right the faster I go until I am unable to trim it to hands off. Stick force in roll becomes quite high when diving for the finish at races. Uncomfortably high. See my previous post in this thread for more explanation of my trim issue.

I had decided to start experimenting with aileron height relative to the wing to see if I could solve the problem this way. The way I figured it was that the left aileron was rigged too high, causing high velocity air on top to create a low pressure area on top, causing the aileron to float up at high speed and therefore a right roll.

I know a picture is worth a thousand words, but I don't have one so I will try to describe what I did: I took a 24 inch ruler and laid it on the top wing skin along the wing rivet lines and also just inside the outboard top rivets on the aileron spar. To ensure consistent measurements, I set the ruler in the same place relative to the back of the wing skin every time. Also, I held the ruler in place by putting pressure right on the 12 inch mark of the ruler.

What I discovered surprised me; the ailerons were rigged the same. However, the wing skin was bent down aft of the rear spar on the right wing above the aileron by as much as 3/16 in. The skin on the left did not have this problem.

So... I gently straightened the skin out on the right, and went flying. Problem solved! It is not perfect, but my spring trim will allow the plane to fly hands off almost the entire speed range of the airplane. Amazing. I have fought this for years, and it took literally 5 minutes to fix once I saw the problem.

I hope this helps someone.
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