One aileron only: Which one is best ? - RC Groups
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Jul 13, 2003, 12:23 AM
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Rsmith's Avatar

One aileron only: Which one is best ?

Hey Guys,
I want to reduce weight on my sp400 Micron pylon plane flying the Calgary rules. I want to do this by removing one aileron servo from the wing (currently one servo buried in each wing panel running each aileron).

If I were to do this, which aileron should I leave active ? For turning the 3 pole pylon course, do I want the left aileron to be active and go UP to bank left or is it better for the right aileron to be active and have it go DOWN for the turn.

By "better" I mean least drag caused by the deflection.
Your thoughts ???

Randy Smith
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Jul 13, 2003, 12:50 AM
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slammin's Avatar
having the one aileron go up will cause less drag and give you "proverse" yaw. Having one aileron go down will give you adverse yaw and more drag
Jul 13, 2003, 12:00 PM
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One Aileron


Our club's pylon races have several pilot's using the one aileron approach to flight control. If your going to use the one aileron system, you may need some additional aileron area, or low speed can be a Expletive deleted by Moderator. Put the working one on the top or right wing as increasing the drag on the top wing will tend to raise the nose. Left wing aileron will lower the nose. A plane that wants to drop the nose in the turns is not a lot of fun to fly.

Couldn't you eliminate one servo and just use one servo to controll both aileron's? Add some linkage and you'll be ready to go... From my experience, two ailerons are better than one... I doubt that you would be able to see much difference in the half ounce weight savings in a 14-15 oz. airplane. Good Luck..... Jeff
Last edited by DaveSawers; Jul 13, 2003 at 01:50 PM.
Jul 14, 2003, 08:28 PM
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Just my cents worth.This approach doesn't sound quite usual to me. It depends on which direction your plane will be rolling most of the time. Most pylon plane rolls to the left to fly its course. The up going aileron causing less drag than the other and so, most single aileron pylon planes usaully have only left aileron. It sounds new to me but I never notice any dropping of nose when I have my left aileron going up during left roll, for my single aileron plane. In fact, the absence of down going aileron not only reduces drag, it also prevents adverse yaw, which in terms helps the roll.
To convince you, other than my own design pylon racers, the K&A model 'Evolution 400' and the 'Feigling' from the Electric Flight uses only left aileron.
Jul 14, 2003, 10:25 PM
Registered Taranis User
Miami Mike's Avatar
Here's a plane with one aileron:

Here's a thread about it. Skip down to the ninth post and read from there for a few comments about the single aileron:
Latest blog entry: Taranis: Aileron-To-Rudder Mix.
Jul 14, 2003, 11:32 PM
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rogwinger's Avatar
Hello Randy

Another two cents for you. I'm sure you have seen the Whisper that I designed. I have over 50 flights on this model and honestly I cannot notice any adverse yaw or pulling the nose up in any maneuver, left or right. This is a very smooth flying aircraft! That's why I like flying it so much. I am using a right hand aileron only. I will say that the roll rate is slower than most people would like for a sport model but on the race course it is more than adequate. In the end all that you can do is build it, fly it and see what works for you.
Jul 16, 2003, 10:57 AM
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Rsmith's Avatar
Thanks everyone for your input.

I guess I will just have to try it and see what happens. I can easily just disable one servo on my current Micron setup and see what happens. Probably increase throw on the active one.....

I am no stranger to one aileron. I used to use one (left) aileron in F3D glow powered pylon planes where we had lots of horsepower. Rolls were a bit non-axial and slower but for just racing around the course where little input is needed, it was just fine. I am just interested if the right vs left debate is more critical on a much smaller plane with less power available.

I'll just try it. thanks,

Jul 21, 2003, 09:11 AM
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I fly right aileron only on a 1 metre MH30 open model pylon in Australia. This has a 22/30/2 motor and 10*1950FAUP on a Graupner 5.5*5.5 for our 3 minute races. The theory behind the right aileron is that the only direction you will want to go in a hurry is to the right (assuming left hand circuits) If you overcook a turn, then you need to roll to the right and an upward right aileron is going to be the quickest way. Also, I would expect that a downward left aileron whilst in a high speed turn would risk a high speed stall of the left wing with fatal results. Touch wood, my model is still alive after 5 years because it has no vices
Jul 21, 2003, 09:15 AM
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PS - Joe, I would hope any pylon model rolls to the right as much as to the left in a race, unless you do rolling circles around the course!!!

Jul 21, 2003, 09:34 AM
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Originally posted by philmaur
PS - Joe, I would hope any pylon model rolls to the right as much as to the left in a race, unless you do rolling circles around the course!!!

Well, that's a very personal style of you. You fly it that way and you like it, so it's best for you. I roll my plane very well on left aileron only and I'm used to it. I don't even need to roll a lot if I keep my flying smooth. Why in the first place do you overcook your left turn anyway? Do you compromise all the left turns just to overcome the few overcooked turns for the entire race?
Every method, there's a theory behind it and it all depends on which one you buy. That's at least what I believe. If you're not quite convinced, go ask the designer of the Graupner Viper, the K&A Evolution and the Electric flight Feigling.
Last edited by Joe Yap; Jul 21, 2003 at 09:37 AM.
Jul 21, 2003, 05:02 PM
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Joe, I agree it's what suits you best - I don't claim to be an aerodynamic expert and the wings I use were acquired from the builder who flew back in the '94 WC - it was his theory and it seemed to have some logic.

I personally haven't had a problem with overbanked turns, but we lost two quick S400 models last Sunday through over tight turns at pylon 1 and I have seen a number of cases of a Hummer which snaps, fortunately to the right, if you give it too much elevator.

Your point about not rolling a lot also matches the view of one of our top local glow pylon flyers, who suggested that the straights should be flown at about a 45 degree bank, not with wings flat. Not sure about this at 3 minute race speeds or on the longer F5D course 'though!

Safe and happy flying

Jul 22, 2003, 08:04 AM
Registered User
For every setup, there's will be it's own pros and cons. For left only aileron, left turns will be smoother and if you are skillful enough to avoid overcooked turns, you'll have the advantage. But for one who does it often, right only aileron may be the ticket for him. If one could not get used to flying on single aileron, twin aileron setup will be the best for him. The idea is to fly the course at smooth as possible to avoid unwanted sharp turns or too many flight corrections. If the particular setup allows you to do that, it'll be your ticket. Even the fastest plane in the race may not be the winner. Ultimately, if you win the race, either by skill or luck, you can 'proof' to everyone that your particular theory is 'correct', even though it may not be the fairess way to do so. Isn't this sounds familiar to you?

BTW, I'm do not disagree the use of right aileron only, but it's just unfamiliar to me. The left aileron only theory mentioned earlier is just what I've learnt from an article from a designer of a pylon racer, which rather makes sense to me, at least.

If people goes to the extreme of reducing drag from the down going ailerons without compromising roll symmetry, maybe someday someone will design a plane with 2 up-going only ailerons. Why not? At least the full-size later version of B-52 uses the theory by forgoing all ailerons for roll control and uses spoilerons instead.