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  #1  
Old 07-29-2019, 11:31 PM
Earl Findlay Earl Findlay is offline
 
Join Date: Jul 2019
Location: Sandpoint, Idaho
Posts: 70
Default A left wing heavy RV-6A

I was able to fly in an RV-6A this morning. What a ride!

One thing that I noticed is that the airplane was very left wing heavy. In other words, it would not fly straight and level hands off. I noticed that the left aileron on this airplane was slightly higher than the right, which would seem to be the cause of the left wing heavy appearance, but I am not certain.

My question, as a soon to be builder .. if this happens on my build, is it something that can be fixed without huge amounts of trouble? Or, is it an "oh $@*@ moment, and you're forever stuck with an airplane that does not fly straight, or face the prospect of rebuilding a portion of the airplane? I suppose that this means at some point, the builder neglected to check something??
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  #2  
Old 07-29-2019, 11:59 PM
arffguy arffguy is offline
 
Join Date: Jan 2005
Location: Elk Grove, CA
Posts: 411
Default

Here you go:

https://www.vansaircraft.com/faq-tec...-a-heavy-wing/


There's plenty of discussion here on the forums too.
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  #3  
Old 07-30-2019, 12:13 AM
BobTurner BobTurner is online now
 
Join Date: Dec 2011
Location: Livermore, CA
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Default

This exact thing happened to me - left wing heavy on my -10. Sighting down the top of the wing I could see the left aileron was slightly higher than the right one, on the outboard end. Maybe 1/32 - 1/16?. Removed the aileron, removed the mounting bracket. Used a file to elongate the hole about 1/32? vertically. Partially filled the hole with JB Weld, re-drilled, filed sides flat. Remounted everything, heavy left wing is now gone. If you need more than a bit of elongation, Vans sells undrilled brackets for just this purpose.
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  #4  
Old 07-30-2019, 12:30 AM
scsmith scsmith is offline
 
Join Date: Jan 2008
Location: Ashland, OR
Posts: 2,573
Default

What Bob Turner is describing is balancing the height of the aileron skin at the hingeline gap with the wing skin. If you lay a straight edge on the wing skin, overhanging enough to go back over the aileron, with the aileron fixed in the true neutral position (lined up tooling holes in tip rib as per the instruction manual), then look at the gap or contact between the straight edge and the aileron skin.

You would like them to touch, or for the aileron to be slightly high, so that the straight edge is lifted up off the wing skin slightly. Something less than a 1/32" or so. You would prefer not to have the aileron skin low. BUT the key is that this arrangement should be the same left and right, and the same at the inboard and outboard ends of the aileron.

It is a safe bet that the aileron on the side that is "light" (meaning it rises if hands off) is set below the wing skin by more than the other side.
The aerodynamic mechanism at work here is something I have explained in other threads. But all you need to do to fix it is as Bob Turner suggests, adjust the hinge bracket up or down as needed, most desirably by making new brackets.
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Last edited by scsmith : 07-30-2019 at 12:33 AM.
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  #5  
Old 07-30-2019, 05:35 AM
BillL BillL is offline
 
Join Date: Sep 2007
Location: Central IL
Posts: 5,516
Default Yes, a heavy wing can be corrected.

Apparently, it is not hard to build a heavy wing. I had one, my 10 friend had one. Yes, a heavy wing is fixable. Undrilled hinges are available for the 7, not sure if the 6 is the same, and none are available for the 10. They can be welded and holes moved.

SCSMITH is the man!
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  #6  
Old 07-30-2019, 06:14 AM
WingsOnWheels WingsOnWheels is offline
 
Join Date: Mar 2009
Location: Plano, TX
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Default

I have a heavy right wing at the moment. I am about 12hrs into my phase 1. For now I added a trim tab to the bottom of the light aileron, once I install the wheel pants and gear leg fairings, I am going to adjust the hinge brackets. I will slot them for testing and then replace once I have determined the correct position. The ailerons are in trail when I hold the wings level, so I am confident the vertical adjustment will solve the problem.
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  #7  
Old 08-11-2019, 08:14 PM
WingsOnWheels WingsOnWheels is offline
 
Join Date: Mar 2009
Location: Plano, TX
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I wanted to follow up on this thread. I had a heavy right wing. After careful measurement, I decided to shift the right (heavy) aileron down 1/8". I test flew it today and my heavy wing is 90% gone. I need to make a few other minor tweaks, but it looks like this was the right way to go!
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  #8  
Old 11-06-2019, 08:34 PM
jpowell13 jpowell13 is offline
 
Join Date: Nov 2008
Location: Baton Rouge, LA
Posts: 671
Default Wing heavy 6A

I've lived with a left wing heavy 6A for too long. Finally tried rotating the nose gear leg fairing trailing edge a few degrees away from the heavy wing and flew today. Problem solved. John
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  #9  
Old 11-07-2019, 09:20 AM
jdmrv7a jdmrv7a is offline
 
Join Date: Jan 2018
Location: DFW
Posts: 65
Default Heavy wing- RV14-A

John,
How far out (left or right) was the ball? Did you add a trim tab or adjustment to the flaps or aileron? Was it just a simple rotation of the nose gear leg fairing?

I am in the process of making some adjustment on my RV 14-A so I can remove the taped-on trim-tab under my left aileron and right side of my rudder.
The Van's "Heavy Wing fix" memo was not written for the RV14-A. Any expert recommendations would be appreciated.
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  #10  
Old 11-07-2019, 04:55 PM
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AAflyer AAflyer is offline
 
Join Date: May 2009
Location: Fort Mill, South Carolina
Posts: 345
Default Trailing edge radius

Why is noone talking about squeezing the trailing edge of the aileron, per Vans plans, to alleviate this condition?
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