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Aileron Trim

N13BN

Well Known Member
I received an aileron trim kit from Van's but the instructions are minimal. Does anyone have any experience with installation on a flying -3?
Thanks

Bill Newkirk
 
Just curious, why would you want aileron trim on a -3? Didn't know Van's even offered one. Personally, I'd get the airplane to fly level with even fuel, then consider any imbalance caused by fuel to be an SA (situational awareness) enhancer as to your fuel condition.
 
trim photo

I received an aileron trim kit from Van's but the instructions are minimal. Does anyone have any experience with installation on a flying -3?
Thanks

Bill Newkirk

Fred Bauer almost has a photo of the install on his -3. Use the magnify feature and you'll be able to see all you need.

http://picasaweb.google.com/airspeedzero/N313RVVansRV3BSN11366FredBauerJr#5225262612441158434

Above 180 mph tas on my -3 the left wing gets heavy. Fuel transfer doesn't help. No problem when yanking & banking, but a real pain on a X-C. Solved the problem by looping three #64 rubber bands together, then putting one end on the stick and the other on the carb heat knob.

After using the rubber bands on the trip to Oshkosh, I decided to give Van's trim a try. Currently trying to find a pair of springs that will work better than those supplied.

Tony
 
Guys, it's just good practice to address the root cause of any wing-heavy condition. Van's has written an excellent article on the subject which can be found here. Yes, it's a pain in the butt to keep drilling aileron mounts and trying them but oh so satifsying when you get the thing to fly hands off.
 
Fred Bauer almost has a photo of the install on his -3. Use the magnify feature and you'll be able to see all you need.

http://picasaweb.google.com/airspeedzero/N313RVVansRV3BSN11366FredBauerJr#5225262612441158434

Above 180 mph tas on my -3 the left wing gets heavy. Fuel transfer doesn't help. No problem when yanking & banking, but a real pain on a X-C. Solved the problem by looping three #64 rubber bands together, then putting one end on the stick and the other on the carb heat knob.

After using the rubber bands on the trip to Oshkosh, I decided to give Van's trim a try. Currently trying to find a pair of springs that will work better than those supplied.

Tony
The flying -4 we bought has no trim tabs yet flies straighter than any certified plane I?ve owned, but it always had a slightly heavy left wing so we installed the manual aileron trim shown in your photo into our -4. Btw, most of the RV?s we considered buying had heavy left wings.

Although we attached the springs to the very bottom of the lever to get maximum leverage, it?s barely effective. But on the positive side this makes small trim changes very easy. We used the supplied springs but had to offset the location of the 90 degree bends on the outboard cotter pins to maximize the pull on the right side.

I suppose it?s true that it affects the ?feel? of the ailerons but I never even noticed it. Although the installation instructions are far from complete, once you find the right tension, it works great and I?m glad we have it.

Even if you built the perfectly rigged ship, given the large speed range RV?s fly, I think having an aileron trim is a good idea. While on a long x-country leg, I?d rather have the reduced fatigue that an aileron trim provides over the fuel situational awareness that holding up a heavy wing provides :)
 
Thanks for the comments

Randy, thanks for the link to Van's article. I had read it in the past but did not remember the info about centering the ball. My ball is NOT centered. So perhaps I should put on a rudder tab. I saw yours at Arlington.

At slow speeds my right wing is heavy but as speed increases the left one is. I love flying my -3, but because it is so "unstable" I am considering installing a single axis AP from Dynon. Yesterday I flew it 4 1/2 hours. It was enjoyable, as usual, but requires constant attention. I'm not sure what is considered 'normal' because my last 700 hours have been in a Taylorcraft, a Murphy Rebel and a C-182. Comments...

Bill Newkirk
 
Randy, thanks for the link to Van's article. I had read it in the past but did not remember the info about centering the ball. My ball is NOT centered. So perhaps I should put on a rudder tab. I saw yours at Arlington.

At slow speeds my right wing is heavy but as speed increases the left one is. I love flying my -3, but because it is so "unstable" I am considering installing a single axis AP from Dynon. Yesterday I flew it 4 1/2 hours. It was enjoyable, as usual, but requires constant attention. I'm not sure what is considered 'normal' because my last 700 hours have been in a Taylorcraft, a Murphy Rebel and a C-182. Comments...

Bill Newkirk
Yep, should've mentioned that, the ball must be centered before messing with any wing heavy issues at all. I have a TruTrak two-axis autopilot and love it. Although when flying around in the local area I often times like just hand-flying the plane just so as to "feel it", this is one of the best parts of the -3.

Though I fly of course with right hand on the stick and left hand on the throttle, I fly with left hand on the stick occasionally just for a change of pace. In turbulence I sometimes use fingertips from both hands on the stick and forearms on my thighs to keep me from bouncing around.

The autopilot is really a nice aid for managing cockpit workload. Indeed, the -3 needs a constant eye on things so when you're looking airport info up in the Flight Guide or consulting a sectional the plane can wander and there's no one to give the stick to while you're working. Such is the plight of the lonely -3 driver, wouldn't have it any other way though!
 
Aileron trim

N13BN,
I don't know what is "normal" for a RV-3 since mine is the only RV of any type I have flown. Mine has no auto-pilot and is dirt-simple VFR only. While it is not nearly as stable as say a C172, it does not require constant attention. I can let go of the stick and look at charts with no problem if the air not rough. Of course I need to look up about every 10sec and maybe make a small adjustment now and then.The ball is centered in cruse and it is just the best flying airplane I ever had the pleasure to fly. I have the aileron trim and find it useful on cross-country as fuel is burned off. If one tank has more fuel than the other, I can remove the slight pressure on the stick to keep the wings level. But I don't see how aileron trim would be very usefull on older -3s without wing tanks. If they have a heavy wing or fly w/o the ball centered, something else needs attention. But I would definitely install it on one with wing tanks.
Bill
 
My -3 is only 1 year old and has factory wings with tanks. Thanks to Tony telling me to look at Fred's photo, I now have some idea of how to install it. Now, in my usual fashion, instead of just getting after it and doing the installation, I'll walk around the plane for about a month wringing my hands and muttering about how much work its going to be. Then, when I finally get around to it, I'll probably be surprised at how easy it was. But my wife says that is what makes me "special."
Thanks for all the comments.

Bill Newkirk
 
heavy wing fixed

Guys, it's just good practice to address the root cause of any wing-heavy condition. Van's has written an excellent article on the subject which can be found here. Yes, it's a pain in the butt to keep drilling aileron mounts and trying them but oh so satifsying when you get the thing to fly hands off.

After putting it off for a very long time, I finally decided to attempt to fix a heavy left wing. Right aileron had been squeezed like a lemon without fixing the problem. Details on how to do it are in Randy's link above. Near as I could measure, the outboard end of the left aileron needed to come down 3/32" to put it perfectly in line with the wing profile. So I dropped it 1/8". When the heavy wing moved from left to right, I knew I was on to something. Moved it back up about 1/32" and with the ball centered there's no heavy wing at any speed.

Thank you Randy!!!

Tony
 
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