A few days ago I posted a thread on how i cut ailerons into the wing of the Parkzone Super Decathelon.

Everything looked and worked well after the build

Today was the first day i took it out for a test run, and .....well it didn't work. The plane was not stable and the aileron didn't seem to do anything. Crashed it very lightly twice and gave up.

I had my doubts about doing it but i said "What the Hell". I think the wing design is the contributing factor here.

I will put on a stock wing and go leave it as is.

Red before you give up on your mod, which looks good by the way, you might want to try this,,,, remove some of the dehedrial, the wing is designed to work with rudder, that is why it has dehedrial in it, if you will take a CF rod or even a couple bamboo skewers and glue them across the the middle of the wing on the bottom and use some packing tape pulled tight on the bottom it will pull your dehedrial out, you will also need to shorten your wing struts. I had a Cub with the exact same style wing and I added ailerons and removed about half the dehedrial and it work perfect. The undercamber isn't going to be a prob, it will still work good

Just read through your first thread, the SD Cub is what I had, it is a great plane but will come very tail heavy and needs a couple mods before you fly it,,, you can also make a steerable tailwheel for your decath and the cub for no extra $$$ very simple mod.

Thanks AJ...

But even flying the plane straight not using the ailerons at all it was very unstable. Tried to straighten out with ailerons and it did nothing.

I will try taking out the ' dehedril' and see if that works.

By the way the cub is a nice flying plane ... flew that today also and it flys better than the Decathelon.

Oh... one other questions, how much of the wing did you cut out for the ailerons? Did i cut enough out?

P.S. do you have any pictures

I would say you did make the ailerons a good size, if the plane was all over the place even in normal flight you need to find what was causing that first, did your mod change your CG. Also if you used a servo from a crashed plane is it working properly, I know when you go from rudder to ailerons on a 3 channel you no longer use the rudder, so did you secure it so it couldn't move and make sure it was centered. The pics I have only show how I set the servo up in the cub wing and ran the cable to the aileron, not a good shot of the aileron itself. don't make your wing flat just remove about half of the dehedrial or a little more than half, now when you do this it will no longer self correct itself, or it will not appear to so be prepared for the change in flight habbits. It will act more like one of your warbirds

The Cub is a sweet flyer, I have had 2, the first I basicaly destroyed because I was a newby and didn't have enough experience to fly it, the second I modded, ailerons went brushless and lipo added a steerable tailwheel, it was a dream to fly.

I ground tested the servo many times to make sure it worked.

I hand launched it twice and both times it was uncontrolable instantly.

i think the rudder servo should be strong enough to keep rudder straight. Check plane after each time and rudder was straight.
Question, how did you fit a lipo in the battery compartment?

Descibe what it did at launch, I mean was it suddenly trying to turn or was it dragging it's tail struggling to gain air speed, or was it the tiniest touch had it wobbling all over. If the ladder applies you need to move your cable to the outer most hole on the horn and middle on the servo. Ailerons work completely different, they sort of rock the plane, like waving the wing, if your throws are set too much it may be that your just not used to it. OR you might be gettnig flutter, to correct that you can loosen each aileron and push it down to 45 deg then run a strip of packing tape across the gap of the wing and aileron, this will reduce the air getting between them and give better control

As to using a lipo in the Cub
I cut out the devider between the top and bottom area and stood it up, also I had cut out the wall from the batt bay into the area behind the motor, this allowed me to push the batt into that area behind the motor.That made gettnig CG easy without adding weight. I had however replaced the ESC and RX I located the ESC behind the motor and put the RX in front of the servo's
I know for me to just say all that sounds insane, sounds like it wouldn't work, but to see it makes perfect since. I wish I had some pics to show you but I have since given the plane to a freind and it is sitting in a closet waiting for him to move. Maybe I can coax him into taking a couple pics

RedGN,

I agree with AJ that you should not give up on your aileron mod. A number of flyers have successfully modified the J3Cub to work with ailerons; the SD should be no different.

Go to the J3Cub thread in this forum. I know that its an extremely long thread, but look up one of the contributers, named "Glacier Girl". He is the most knowledgeable flyer when it comes to J3Cub modifications, so if you PM him, I'm sure that he will be able to help you sort out the problems with your SD.

I recently upgraded my J3Cub to brushless/LiPo. I bought a 3-cell 800mah LiPo from Heads-Up-RC (on ebay) that fits the J3 battery compartment like it was made for it.