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  #1  
Old 05-07-2016, 07:58 AM
Nate-ISU Nate-ISU is offline
 
Join Date: Mar 2013
Location: Indianapolis
Posts: 51
Default Old Build (flying) - Flap/Aileron Alignment

Hello all. Below is a plane I purchased. I did my research but being a first time buyer and RV owner, there were things I didn't notice initially which an experienced builder/-4 guru would have. Live and learn. A very brief history--this is an older build (first flight in 1983) and the logs show that it was disassembled in 1998, reassembled in 1999 by Ray Williams and sold in 2000. It has accrued ~700/hrs since this point. Whether this is relevant or not is hard to say but is worth mentioning.

To the point--you can see in the first few images below (left inboard/outboard) that the trailing edge of the flap/aileron/tips don't align. I don't see this as being very significant but just making note of it. I attribute it to being a very early build and the attention to detail that I see in these new RVs that look like certified aircraft (ya'll have some beautiful RV's!) just wasn't there with the early builders/kits. However, the right flap/aileron alignment is off considerably and yet, the inboard of both L/R flaps meet the fuse the same.

The kicker? Airplane flies hands off, which I imagine is why I didn't notice it initially. The RV grin obscured my view. What you see in the images is what the plane looks like in S+L flight. The stick is centered as well. I attribute this to the manual trim tab on the left aileron that is compensating for this.

So curiosity is getting the best of me. What's the root cause here? It's ugly and isn't up to the standards I see on the forums here, but should I be concerned? I imagine it's been flying at least 700/hrs like this (since re-assembled) and possibly more, perhaps even built this way? Thoughts?


Left - Outboard


Left - Inboard



Right - Outboard


Right - Intboard
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  #2  
Old 05-07-2016, 08:57 AM
Michael Henning Michael Henning is offline
 
Join Date: Jun 2011
Location: Nashua, NH
Posts: 536
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Are the the control surfaces twisted? To have that much deflection, something must be way off. In S & L, my control surfaces all line up, no trim tabs.
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  #3  
Old 05-07-2016, 11:33 AM
Michael Henning Michael Henning is offline
 
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In the picture of the left outboard, the gap between the wing and aileron is not constant. It looks like the builder lowered the hinge point to line up with the flap. On the right wing, it almost looks like the flap is not "up" all the way. I would find a local 4 builder to look at it.
Do you have the build manual and drawings?
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RV-4 #2750
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  #4  
Old 05-07-2016, 12:11 PM
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Mike S Mike S is offline
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Location: Dayton Airpark, NV A34
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Quote:
Originally Posted by Nate-ISU View Post
Airplane flies hands off, which I imagine is why I didn't notice it initially. The RV grin obscured my view. What you see in the images is what the plane looks like in S+L flight. The stick is centered as well. I attribute this to the manual trim tab on the left aileron that is compensating for this.




Left - Inboard





Right - Intboard
First off, as you say it is flying hands off---good. Most likely due to the trim tab.

The aileron and flap trailing edge shape is a big factor on these planes, and from what I can see in your photos, the trailing edge appears to bulge outboard of the trim tab in the first photo, and the flap trailing edge looks a bit strange in the outboard end in the second photo-----photos that I have copied above. These could be photo distortion, or actually the trailing edges being not uniform across the entire surface-----this would be a good thing to check. Check out this thread http://www.vansairforce.com/communit...d.php?t=132215

Unless this is a really big issue to you, you just might be better off to enjoy how it flies, and accept how it looks. If you go after getting the looks top notch, you may end up chasing a lot of newly induced gremlins in the handling side of the equation.
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Rv-10, N210LM.

Flying as of 12/4/2010

Phase 1 done, 2/4/2011

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Last edited by Mike S : 05-07-2016 at 12:21 PM.
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  #5  
Old 05-07-2016, 12:30 PM
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az_gila az_gila is offline
 
Join Date: Jan 2005
Location: 57AZ - NW Tucson area
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Post Non-uniform TE

The non-uniform trailing edges were a possible 'feature' of the early kits caused by tolerances in the not yet pre-punched parts.

This is from the early RV-6 instructions on fitting the flaps...



I'm sure the RV-4 instructions were similar.

It looks like the builder didn't purchase the wider hinge. In my case I needed it on one side and not the other.
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Half completed RV-10 QB purchased
RV-6A N61GX - finally flying
Grumman Tiger N12GA - flying
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  #6  
Old 05-07-2016, 01:52 PM
Nate-ISU Nate-ISU is offline
 
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Location: Indianapolis
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Appreciate the comments up to this point!

Are the the control surfaces twisted?

Not that is visible from the eye that I can tell. I could place a 2x4 or similar across the surface and check whatever gap there may be but if it were twisted to such a degree to cause that sort of alignment issue, I believe it'd be easy to see with the naked eye. Unless I'm mis-understanding your question.

Do you have the build manual and drawings?

I have the original plans & logbooks. No documentation/pictures of the build process.

It looks like the builder lowered the hinge point to line up with the flap. On the right wing, it almost looks like the flap is not "up" all the way

Good observation on the aileron. As for the flap not being 'up,' I agree, that's exactly what it looks like--but it definitely meets at the fuse consistent with the left flap and there is no play if you attempt to 'pull up' lightly on the flaps when fully retracted as they are here. That's what boggles my mind; visually, it looks as if it needs to retract further, but any more and it would be far above where it meets the fuse, just 'moving' the problem.

Unless this is a really big issue to you, you just might be better off to enjoy how it flies, and accept how it looks.

Other than looking ugly, its apparently been flying this way for years and like I said, flies hands off so I can't complain other than the visual aspect (assuming it's not a safety of flight issue--asking those sorts of questions are like asking for legal advice on the internet, I need to just speak to a builder) My plan has been to fly it until FWF needs something major then strip it down and fix the nuances but thought it was worth fielding the questions to this awesome community.
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  #7  
Old 05-07-2016, 01:59 PM
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Ironflight Ironflight is offline
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If you like the way it flies, and it's all about looks, it's simple to fix. Park with the flaps down....
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  #8  
Old 05-07-2016, 03:09 PM
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az_gila az_gila is offline
 
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Location: 57AZ - NW Tucson area
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Smile Measure

Pictures and eyeballs can be deceiving.

Set the flaps and ailerons to what you think is neutral (or the flies straight) position and get a digital level and measure both the flaps and ailerons at 6 inch intervals from root to tip.

This will show any left/right differences and also measure any twist in the control surfaces.
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Gil Alexander
EAA Technical Counselor, Airframe Mechanic
Half completed RV-10 QB purchased
RV-6A N61GX - finally flying
Grumman Tiger N12GA - flying
La Cholla Airpark (57AZ) Tucson AZ
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  #9  
Old 05-07-2016, 04:51 PM
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Larco Larco is offline
 
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Location: DVT Phoenix
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Older builders used to see this sort of thing quite often. There was very little networking among builders or good examples to follow.
If the integrity is there, the build is safe and it flys well, I would not be to anxious to open up the possible huge can of worms to just make it look better. It may end up being a ton more work than anticipated
Back then We noticed right off that the builders of these planes had just as much fun as ones that looked better cosmetically.
Like Ironflight said, Park it with the flaps down like most of do anyway and enjoy the plane.
of course I am assuming that this plane has had many conditional inspections and found in a condition for safe flight. Have fun, Spring is here.
:-) Larry
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  #10  
Old 05-08-2016, 07:22 AM
Billythekid Billythekid is offline
 
Join Date: Jan 2016
Location: South California
Posts: 244
Default the course

here is what i would do...
turn on the shop radio to 50'S music , sit in a chair with feet up on something , crack open a beer, and sit and stare at the issue. stare at the whole thing for a while, you may arrive at the problem some time later and when you are at that point go look at the plans closely and you may find where things went off script. and how it got that way, then make a call to vans and ask questions, and also post here.
plan b...
enjoy it and dont get attached to it, leave the option open to sell it and get one that is more to your standards. and enjoy it while you have it..
billythekd, collecting parts, gaining knowledge, learning
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