DennisRhodes

DennisRhodes

Well Known Member
HAve just installed RV9 wings,set the incedince angle. Drilled in the rear spar bolt, installed flaps and have a question about the proper "zero" position of the aileron. Do I just call zero at the position of the adjacent flap trailing edge or should it be at the wing tip trailing edge . They are not the same! I'm guessing the flaps in the "up against the fuselage" should be the aileron zero position. I would like to position them at the correct position to the wing. Just not sure where that is. Maybe I missed something in the plans on that. Comments? Would be nice to have a template of the airfoil to check the trailing edge position on both flaps and ailerons. DRR
 
I believe the plans show how to reference the tooling holes in the outboard most main wing rib and the aileron rib to verify the aileron trailing edge is aligned with the cord line.
 
Assuming there is no twist in the flaps or ailerons... They should match the ailerons when the ailerons are set per the plans using the alignment holes in the outboard ribs. Study the instructions as there is a half way decent description of how to align the ailerons. From there, you just gotta' make the flaps fit. You could make an alignment template from the properly aligned ailerons if you wanted to convince yourself. I had to do all kinds of crazy stuff to the flaps at the fuselage intersection (root of the flaps) as I know I had some twist in my flaps. It will still fly fine, I promise :).
 
Tooling alignment holes.

Thanks , I'll go back and look for those tooling alignment holes. Sounds like that's the puzzle piece I was missing. I'm almost positive that one of the wing tips will require some fiberglass rework having missed that.
 
Flaps

scard said:
Assuming there is no twist in the flaps or ailerons... They should match the ailerons when the ailerons are set per the plans using the alignment holes in the outboard ribs. Study the instructions as there is a half way decent description of how to align the ailerons. From there, you just gotta' make the flaps fit. You could make an alignment template from the properly aligned ailerons if you wanted to convince yourself. I had to do all kinds of crazy stuff to the flaps at the fuselage intersection (root of the flaps) as I know I had some twist in my flaps. It will still fly fine, I promise :).
Click to expand...
Scott,
Not to hijack the thread but what kind of problems at the root intersection did you have? Reason I ask, my right flap is just perfect, but when I align left aileron/flap at the root intersection my flap tab is is about 3/4" low(not against belly of the fuse). Checked trailing edge-straight as an arrow, no twist either. Checked with Van's, advised me to leave it alone, or if it really bothered me to just bend the flap tab up to touch the fuse. Just curious to see if your issues were the same. I think that it's the flap hinge brackets.
Mike H 9A/8A
 
DennisRhodes said:
Thanks , I'll go back and look for those tooling alignment holes. Sounds like that's the puzzle piece I was missing. I'm almost positive that one of the wing tips will require some fiberglass rework having missed that.
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Dennis-There's a spot in your plans that told you to fabricate an aileron alignment tool before you assembled your wings. It won't be too hard to make after the fact, I don't think, so you should be OK.

As mentioned above, you must center the ailerons first. Everything else, flaps and wingtips, then align to the ailerons as much as possible. As others have also suggested above, it's very common to have a little twist in the long 8-ft flap so it may be difficult to get the flap to line up with both the aileron and the fuselage bottom skin at the same time. If so, you'll just have to decide to match the aileron, match the fuselage, or split the difference.

Good luck.
 
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one good flap deserves another

I've seen rv's where the amount of joggling required can vary a little bit from one flap over the other. Logically it seems like that shouldn't be the case, but I guess by the time you're caring about this, you have already committed the wings. So then it's just a matter of doing whatever it takes to set the zero position according to the tooling holes. I think the norm is that you have to joggle both flaps to get the gap seal to lay flat on the fuse bottom skin in the zero position.

If you don't have enough really long angle stock lying around your shop, go to lowes and buy two cheap long metal rulers from the hardware section. It's cheaper than buying a comparable length of alum angle stock, and it's perfectly straight, whereas alum angle stock may not be at that length. You can drill holes into the rulers to mount to the rigging holes, and voila- a perfect rigging tool.

I also agree that the directions influence builders to do their wingtips too early. I think the right time to do the wing tips is after the ailerons are rigged. It seems a lot of builders realize the tips need to be tweaked at this stage.
 
Aileron Alignment

DennisRhodes said:
Do I just call zero at the position of the adjacent flap trailing edge or should it be at the wing tip trailing edge [/SIZE]. They are not the same! DRR
Click to expand...

Are your wing tips mounted already? If they are, then are they riveted or screwed on? If I'm not mistaken, the Van's designed aileron trailing edge alignment tool can only be used if the wingtips are off the wing.
 
Tips are screwed on

I did screw the tips on with countersunk and nut plates . I knew that pay off one day , just didn't know it would it would be so soon!. The amount of flange on the 9 wing for that ATTACHMENT IS MARGINAL. The RV7 has a bit more flange to work with. Thanks for the info. I bought the 9 kit from an individual who had already built the ailerons and had the quick built wings. So I didn't get the advantage of all the details on the alignment holes . I believe those assembly drawings are still rolled up in the storage box!
 
Everything keys off the aileron neutral position. Find that neutral position, then align the trailing edge of the flap and the wingtip to it. I did all that in my basement using the outer rib tooling holes as called out in the plans. The end result translated well enough when the wings were finally spliced to the fuselage.

30tt46v.jpg

I'm not sure an aileron alignment tool is going to be all that helpful in your particular situation. The tool is primarily used to help adjust/align the aileron control tube after the aileron neutral position is determined.
 
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FYI - After using the straight edge to align my ailerons, I had to "adjust the trailing edge of the wing tips to meet the aileron. This required the removal of the wing tip ribs and re-drilling them to the fiberglass, cutting the trailing edge of the wing tips, moving them up, and re-fiberglassing the tips closed.

Like the others, my left flap hangs below the fuselage while the right one does not. Go figure.

The plane flies straight and level but does roll right when stalled.
 
I know I read this here, but I read that you can cut the tips on the ends(on a horizontal), move it to line it up to the ailerons and then repoxy it all together, no redrilling holes.
 
Found the tooling holes

I removed the tip and found the tooling holes as described. Also found the aileron alignment tool the prior builder had alreaded fabricated and marked up. The ailerons adjusted out fine and align up perfectly with the flaps. That leaves me with only one tip to tweek with some fiberglas and all will be well. Thanks for the help
 
...and rest assured that adjusting just the trailing edge of one tip can make a whole lot of difference. The arm on the roll moment of a tip trailing edge is huge compared to the rest of the airframe. You're headed down the right path. Cheers!
 
Reviving an old thread.

I rigged my aileron using Van's tool per the plans. However, I thought I read somewhere that if the ailerons are rigged slightly high it will give you a higher cruise speed. Am I imagining this? I adjusted my ailerons today 2 turns up and felt like the plane was slower. Surely some of the speed gurus have played with rigging to get more speed. Anyone have any thoughts?
 
Only the -10 has reflex, Tony....

....of 3 *. You then match the flaps to them, 3 degrees up.

Aero engineers will probably chime in but my guess is that the 6, 7, 8 with their short, low aspect ratio wings will carry a penalty with reflexed ailerons/flaps.

The -10 has around a 6.8:1 (33' wingspan) aspect ratio and the others around 4.5:1, not counting the -9,

Best,
 
pierre smith said:
Aero engineers will probably chime in but my guess is that the 6, 7, 8 with their short, low aspect ratio wings will carry a penalty with reflexed ailerons/flaps.
Click to expand...

Yeah, I don't think it did anything helpful going up with them. If anything, definitely slower. I will go back to where they were at. I still think that someone must have done some scientific testing to see if an alternate rig will produce higher speeds. I didn't mind testing this myself, after-all I am flying around in circles in my phase I test box anyway.

It does make sense that the Van's rig setting is the "null" zone and no benefit in going up or down.
 
Anyone that has their ailerons rigged using Van's rigging tool as per plans. Can you tell me does the aileron fair with the lower and upper wing skins evenly? Seems like mine are down slightly, they fair with the upper surface but down a degree or two with the bottom. I don't want to pull the wingtips to recheck if I can help it.
 
Tony,

IIRC, they do not fair with either the top or bottom.

BTW, I packed my rigging tool in the camper so it will make the trip to OSH with us. If you don't need it, let me know and I'll remove it from the pile.
 
A possible alternative approach to setting the aileron and flaps is to make an "alignment tool" that sits on top of the wing. This allows you to check if the trailing edge of the aileron and flap are in the correct position relative to the wing along the entire length of the wing rather than just at the wing tip using Vans alignment tool.
I made up an alignment tool that sits on the top of the wing from pieces of 2 x 1" timber glued together with bondo. This tool was calibrated against the outboard aileron tip after the tip was correctly located using the Vans alignment tool. I then used the tool to measure the correct trailing edge position of the aileron and flap at a number of positions along the span of the wing and set each of them at the "average" position to allow for any twist.

Originally, using the Vans alignment tool only, I had a somewhat heavy left wing, one flap hung slightly below the fuselage and the left wing would usually drop in the stall. Maybe I was lucky but all these issues were resolved after resetting the ailerons and flaps using my wing top alignment tool.

Fin
9A
 
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Thanks Bill and Fin,

Bill, yes keep that tool with you for now. I may pull my tips and recheck my alignment. The plane flies straight and true, just can't help messing with things.

Fin, your tool sounds like a good idea. Good way to reset your rig if you like to tweek like I do.
 
on the same page

I'm exactly where you are.

I just drilled my rear spar and front wing attach angles.

I made my aileron position tool from AL angle with a point on the end.

The plans show a wooden one.

So far, it looks like my ailerons match up to the flaps when they're fully retracted.

But.....my vent lines are too short to reach the fuel tank:eek:

Its always something....

Dave
 
more on this topic

I have been reading through this thread with interest. My 7, is 18 hrs. into phase 1. In straight and level flight the ailerons line up exactly with the wing-tips, which is how they are on the ground, without air loads. They were rigged using the tool and method in the plans. The flaps trailing edges were aligned to the ailerons. But in flight, the flaps ride higher -- about 1/2 inch above the aileron trailing edges. I am thinking of adjusting the flaps to 1/2 inch below the ailerons with no air load so as to be aligned in flight. Would this make sense? Do others have this small amount of play in the flap position? :confused:
 
I played with my rigging (both flaps and ailerons) to see if drooping flaps gave any speed improvement to no avail. I also went both ways with my ailerons, down and up. Nothing beat stock.

Now I have my ailerons rigged per the manual and the flaps sucked up tight with about a 1/8" gap at the INBD flap to fuslage. The flaps don't line up with the ailerons and the ailerons are close to the tips. However, You only see this in flight. On the ground flaps down and stick to the side, I'd say they look perfect!

I wouldn't drop your flaps. If you are flying along just tap your flap switch for a split second while watching your IAS and see what happens. You want them up as far as they can go.
 
We had similar issues BEFORE, we read the ENTIRE instructions for the alignment process. There is the jig that goes on the bellcrank and the tubes and the sticks. At first using the tooling holes the ailerons were about 1/2 inch above the flaps. After going through the entire alignment process and adjusting the entire system, the flaps are aligned with the ailerons. but the wing tips were high. The tips were cut and aligned with the ailerons and re assembles. Stalls drop straight ahead and flies straight.
 
Flaps Ride higher

My flaps ride about 1/8 higher than my ailerons in flight. Tried adgusting them, no change. Went back to stock ( both line up on the ground).
 
I rigged my ailerons the other day using a laser level to match the tooling holes and the trailing edge. Both ailerons are perfect. The right side is completely even with the flaps. The left side flap is tucked up tight to the fuse but still off by about 1/32 to 1/16, which raises the question... which is more important... that the ailerons are perfectly in trail or that it should match its flap companion?
 
joggle the flap

The alignment of the ailerons is simply done so that both ailerons are in the neutral position when the stick is in the neutral position. The flaps do not enter the picture.

If the flaps are not going all the way to neutral in the full-up position (thus aligning with the aileron), then you have to joggle the flap seal and adjust the down rod accordingly. Not everyone seems to find it necessary to joggle the flap to get the right alignment, but when you consider the geometry of the wings coming into the fuse at a small angle, it's natural that a joggle should be typical/expected for proper alignment.

For anyone just getting to this stage of alignment, here's a sequence of pics showing my flap and aileron rigging process. Seeing the neutral position clearly is a bit of a trick. I bought two cheap long metal rulers from home depot and drilled/bolted them to the wing tip so that I could project the neutral line from the tooling holes outward. This made it real easy to see when the ailerons were neutral as you tweak all the push rods to get things lined up. There's a picture of a joggled flap in the sequence.
http://donka.net/gallery/rv7fusewrapup?page=9

Thanks,

Don
 
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If, after rigging the ailerons to the end rib tooling holes and aligning the flaps, you find that the flap inboard edge is slightly below the fuse, as I did, you could consider making a small joggled fairing:

details014.jpg


I simply cut off the bottom skin extensions from the flaps (both of my flaps were slightly below), drilled out 3 of the rivets holding the skin on the inboard most flap rib, fabricated the joggled fairing on the workbench, and bonded/flush pop riveted the unit onto the end of the flap. It was much easier for me to make an acceptable fairing on the bench vs working with the excess skin extension on the flap.

Where the flap fairing rides against the fuse skin I used some UHMW tape to avoid scuffing the underside of the plane. The joggled fairing is "flexed" whereby it provides just a bit of pressure against the underside of the plane. Been on for 300+ hrs and I like the finished look of the fairing.

Hope this is of value and of course,

Cheers,

db
 
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Nope---the flaps need to be aligned with the ailerons which are aligned with the cordline of the wing (via the outboard wing rib tooling holes)--not the underside of the fuselage. Now if the flaps are below the wing cordline, then you are flying around with the flaps partially deployed.

Cheers,
db
 
db1yg said:
If, after rigging the ailerons to the end rib tooling holes and aligning the flaps, you find that the flap inboard edge is slightly below the fuse, as I did, you could consider making a small joggled fairing
Click to expand...
This may have already been mentioned, but this scenario suggests a flap with built-in twist. It's much harder to build a perfectly straight RV-9 flap than other 2 seat RVs because it's so much longer. You will either need to live with the flap hanging low at the fuselage, and/or joggle it like Dave is, or build new flap. I have a one flap that has 1/4" twist but it is down on the outboard edge--it matches at the fuselage but not at the aileron. There's not really any joggle solution for twist in that direction. I'll probably rebuild it, but will likely fly first, just to see what the effects are. Ken Scott at Vans told me a long time ago that it will probably be unnoticeable, but I'm still curious.
 
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