Aileron setup help
 

Hi there,

Pretty much finished my reborn Sig Skybolt and I have everything lined up except I want to get more movement out of my ailerons on both low and high rates. I talked to a guy and he figured I do not have to go to a large control horn on the bottom wing, it should be able to be adjusted with the radio. I am using a Spektrum DX7 and was wondering which function I would choose to fix this issue?

Input would be appreciated. I am using dual rates on the ailerons as well...

Thanks

RE: Aileron setup help
 

I know nothing about your brand of radio. Most though have a ATV or travel adjustment. You can turn it up past 100% in most cases. You could also change the geometry of the linkage but the radio is a better option.

David

RE: Aileron setup help
 

Hi Brrzee,

The DX7 has it all in its menu. You can adjust the movement of the servo for Ailerons up to 150%. How's it done you ask, simple. With the radio already turned on hold down the select key and push the scroll down key directly above it, this will place you into the correct menu for this change. Once in the menu, using the scroll up key to find your way to a menu called [TRAVEL ADJUST]. Once there you will need to push the select button repeatedly until the arrow is next to AILE, then use the increase button to change the value up to 150% for left aileron and then whilst holding the aileron stick to the right (this selects right aileron, you will see the little arrow move from left to right when you move the stick) increase that to 150%. Remember that 150% is fine, if your servos can move that far. I tend to have the plane turned on electrically and whilst I make the changes to the radio I can check it on the plane straight away, just by moving the stick left or right. Hope this helps.

RE: Aileron setup help
 

thanks for the info, I figured it was the travel adjust option to make the adjustments.

RE: Aileron setup help
 

You don't have to, but it is easier and more accurate to simply adjust your rigging.

Use the farthest hole on the servo arm if the pushrod isn't out there already. It takes only about 20 seconds to move a pushrod connection.

My setup right now is with the pushrod in the next to farthest hole in the servo arm. It goes to the 3rd hole out on the aileron horn. And the airplane rolls quite fast. I've had the pushrod in the 2nd hole out on the aileron horn, but it was too fast for my wishes when using high rates. I'm betting you'd have liked that roll rate.

Thanks for bringing up this question, because it made me go look at my rigging. Since there are farther out holes on both the servo arm and aileron horn, I can probably move the pushrod out equally on both at the same time. Why do that? Same reason you want to change throws on the airplane instead of in your radio. It's more sensible to do it that way. For accuracy and leverage.

BTW, if you really want more effective ailerons, you need to read up on the problem the ARF rigging causes with the Skybolt and most smaller ARF biplanes.

RE: Aileron setup help
 

The hardware and design for connecting many of the smaller ARF's ailerons is flawed. It uses whatever horns are used for rudders, elevators, and such.

What you wind up having is 3 different throw amounts every time you move the aileron stick. You got 4 ailerons and two go the same amount, while one of the upper ailerons goes a different amount than the lowers, and the other upper aileron goes yet an entirely different amount than the other three.

Say you want 20 degrees of aileron movement. What you get is the two bottom ailerons going 20 degrees. Kewl. But one of the upper ailerons winds up going 23 degrees and the other goes 26 degrees. Sound sensible to you?

RE: Aileron setup help
 

Rock, I see what you're talking about.

My question is; does it really matter for a sport plane?

I've had two CG Ultimates, one I built and the other an ARF. Both had the "flawed" set-up you show; but they flew just fine.

Was I missing something?

I'm building a GP Super AeroMaster, and have a Sig Skybolt kit for a future project.

Some more info (assymetric roll rates, etc.) on potential problems here would be appreciated.

.

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RE: Aileron setup help
 

Were you missing something?

Yeah, the way the model flies when all 4 aileron throws are the same.

The roll rates aren't going to be different clockwise to counter clockwise since the inequality works the same both ways.

What does happen is that having all 4 ailerons throw the same gives 4 outer wings that reach stall AOA more nearly equal. And it also happens with the stock rigging that one of 4 will have a lot quicker stall. You could say that the bad setup creates washout on one of the pair on one side while creating even greater washin on one of the pair on the other side, while no washout or washin is created on the lower halves at all.

I've flown a couple of other ARF Skybolts other than mine. Mine shows me no real tendency to snap out of stuff unexpectedly. I got no idea if that's because I've got mine better balanced, or if I'm just more familiar with mine. But the others caught me by surprise and didn't seem as easy to fly accurately. I also didn't feel at all comfortable slowing those others on landing like I do with mine. Probably just familiarity, and respect for other peoples models. Who knows.

I first saw the problem when I was assembling my World Models Ultimate 40, and fixed it before I ever flew it. And fixed the Skybolt on assembly. So I've never flown and gotten used to a biplane with the screwed up aileron rigging. It would be really interesting to have gotten used to the screwed up rigging and fixed it and gotten to see how much effect the cleaner rigging gives. But not "really interesting" enough to screw up my excellent flying Skybolt.

There are lots of models flying around with too forward a CG for "safety's sake". And lots of other details that are known flaws. And people are perfectly happy with 'em. kewl.....