Aileron Servo
04-09-2004 | 08:29 AM
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From: Indian Trail,
NC
Aileron Servo
It seems that the travel for the ailerons on my plane calls for more up then down travel. Since it's only using a single servo, what's the best way to do this?
04-09-2004 | 09:33 AM
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RE: Aileron Servo
Don't put the link at 90 degrees to each other on the servo. Put it at say the 10 oclock and 2 oclock positions. You can use the star wheel and put it off center. That will give you more one way than the other. You just need to make sure to use the right side to get more up than down. You can also move the horn on the aileron itself to acheive it, but it is better to do it on the servo wheel.
04-09-2004 | 11:49 AM
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From: Indian Trail,
NC
RE: Aileron Servo
Thanks.
Are Z-Bends for the connections on the servos the best way to mount normally. I've been using Kwik Connects for all my other connections to the servos. Seems like I see alot of pictures and drawings with people using z-bends.
Are Z-Bends for the connections on the servos the best way to mount normally. I've been using Kwik Connects for all my other connections to the servos. Seems like I see alot of pictures and drawings with people using z-bends.
04-09-2004 | 03:07 PM
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From: Laurel, MD,
RE: Aileron Servo
If your ailerons use torque rods (which most trainers do), you can also get the effect (aileron differntial) by bending the torque rod arms forwards slightly and shortening the pushrods to match. You can also just shorten the pushrods a little, which as the effect of moving the arms forwards and reflexing the ailerons a little bit.
04-09-2004 | 08:19 PM
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From: Douglasville,
GA
RE: Aileron Servo
It may be a bit hard to visualize if you've never setup that way before.
If you have a single-aileron wing to play with, set it up and you'll see.
If you have a single-aileron wing to play with, set it up and you'll see.
04-09-2004 | 10:54 PM
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RE: Aileron Servo
Geistware,
Look at Mike's graphic. You'll notice that with the 6 point star there will be less throw to the front (less down), which is what you need for aileron differential.
Griffin,
You may be curious as to the reason for less down, or aileron differential. In some planes (trianers quite often), equal down throw will cause "adverse yaw", which means that the plane will "yaw", or the nose will turn in the opposite direction of the "roll" input given with ailerons. The reason it happens is; the downward deflected aileron, while increasing lift, will also increase drag. The increased drag slows that wing which results in the plane's nose swinging towards the slower wing.
For example, you give left aileron command which will cause the plane to roll left (the direction of the intended turn), but the right aileron drops, which CAN cause the right wing to slow a bit, thus causing the nose to swing to the right.
By making down aileron a bit less you can over come the tendency towards adverse yaw.
Does that help at all?
Dennis-
Look at Mike's graphic. You'll notice that with the 6 point star there will be less throw to the front (less down), which is what you need for aileron differential.
Griffin,
You may be curious as to the reason for less down, or aileron differential. In some planes (trianers quite often), equal down throw will cause "adverse yaw", which means that the plane will "yaw", or the nose will turn in the opposite direction of the "roll" input given with ailerons. The reason it happens is; the downward deflected aileron, while increasing lift, will also increase drag. The increased drag slows that wing which results in the plane's nose swinging towards the slower wing.
For example, you give left aileron command which will cause the plane to roll left (the direction of the intended turn), but the right aileron drops, which CAN cause the right wing to slow a bit, thus causing the nose to swing to the right.
By making down aileron a bit less you can over come the tendency towards adverse yaw.
Does that help at all?
Dennis-
04-06-2005 | 02:17 PM
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From: a place in,
NJ
RE: Aileron Servo
ORIGINAL: DBCherry
Geistware,
Look at Mike's graphic. You'll notice that with the 6 point star there will be less throw to the front (less down), which is what you need for aileron differential.
Griffin,
You may be curious as to the reason for less down, or aileron differential. In some planes (trianers quite often), equal down throw will cause "adverse yaw", which means that the plane will "yaw", or the nose will turn in the opposite direction of the "roll" input given with ailerons. The reason it happens is; the downward deflected aileron, while increasing lift, will also increase drag. The increased drag slows that wing which results in the plane's nose swinging towards the slower wing.
For example, you give left aileron command which will cause the plane to roll left (the direction of the intended turn), but the right aileron drops, which CAN cause the right wing to slow a bit, thus causing the nose to swing to the right.
By making down aileron a bit less you can over come the tendency towards adverse yaw.
Does that help at all?
Dennis-
Geistware,
Look at Mike's graphic. You'll notice that with the 6 point star there will be less throw to the front (less down), which is what you need for aileron differential.
Griffin,
You may be curious as to the reason for less down, or aileron differential. In some planes (trianers quite often), equal down throw will cause "adverse yaw", which means that the plane will "yaw", or the nose will turn in the opposite direction of the "roll" input given with ailerons. The reason it happens is; the downward deflected aileron, while increasing lift, will also increase drag. The increased drag slows that wing which results in the plane's nose swinging towards the slower wing.
For example, you give left aileron command which will cause the plane to roll left (the direction of the intended turn), but the right aileron drops, which CAN cause the right wing to slow a bit, thus causing the nose to swing to the right.
By making down aileron a bit less you can over come the tendency towards adverse yaw.
Does that help at all?
Dennis-
04-06-2005 | 02:52 PM
#11
RE: Aileron Servo
They have rudders in full scale planes too, but they also build differential into the aileron system in most including air transport size. Many do it by hinging the ailerons at the top, Friese ailerons I believe is the term. Why not take advantage of all available methods. He will still need to learn rudder application as the differential won't handle it all, just help.
04-08-2005 | 12:53 PM
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From: Laurel, MD,
RE: Aileron Servo
EPA will do nothing for him if he is setting up a 2-servo wing with a y-harness.
Think about it. All you'll wind up doing with EPA is making ONE aileron go up more than down as desired. But then the other will go down more than up.
To make use of EPA to get this kind of thing, you need to use 2 channels. Then, you could use the radio's mixing to make it work.
Think about it. All you'll wind up doing with EPA is making ONE aileron go up more than down as desired. But then the other will go down more than up.
To make use of EPA to get this kind of thing, you need to use 2 channels. Then, you could use the radio's mixing to make it work.
04-08-2005 | 01:16 PM
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From: Springtown,
TX
RE: Aileron Servo
Montague is right. And, he was referring to using a Y harness. If you use two different channels, then you could use the epa for differential, but with two channels you have to make sure you plug them into the same channel each time. Y harness is much simpler. It's all I use, so far. I'm sure I'll eventually use separate channels, if I want flaperons or something, but so far, that hasn't been necessary.!
04-08-2005 | 01:41 PM
#18
RE: Aileron Servo
When I use 2 channels, I mark the plugs by putting a short piece of heat shrink on one of the pairs. Many methods available to assure correct connections.
2slow2matter- Actually, he was talking about a single servo installation so there would be no Y-harness. After he he sets the differential he COULD use EPA to control total throw if he can't get it close enough with linkage positioning on the various arms. EPA or D/R would sacrifice resolution somewhat so the mechanical methods should be used first. IMHO
2slow2matter- Actually, he was talking about a single servo installation so there would be no Y-harness. After he he sets the differential he COULD use EPA to control total throw if he can't get it close enough with linkage positioning on the various arms. EPA or D/R would sacrifice resolution somewhat so the mechanical methods should be used first. IMHO
04-08-2005 | 02:31 PM
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From: Springtown,
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RE: Aileron Servo
my bad, guess I should go back and read the original post first. It's been a while since I read that first post, and we all go off on dual servos, so on.
You can use EPA to adjust total throw, but not differential. That HAS to be done mechanically with a torque rod setup.
The heat shrink tube idea is a great one. I will use that one when I use dual channels!
You can use EPA to adjust total throw, but not differential. That HAS to be done mechanically with a torque rod setup.
The heat shrink tube idea is a great one. I will use that one when I use dual channels!
04-08-2005 | 02:52 PM
#20
RE: Aileron Servo
There has been at least 1 other thread running this week where he is running dual ailerons, perhaps you were thinking of that one. He was having differential questions also. dejevu- dejevu- dejevu- dejevu ya know what I mean?
04-08-2005 | 02:54 PM
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From: Laurel, MD,
RE: Aileron Servo
oops, I mixed up threads or something.
But EPA still won't work in a 1 servo wing either. Though you can fine tune a little with it, it's still not going to be that useful.
I think someone else previously mentioned "close enough" is good enough. You don't need the exact throws recommended, just get it close and the plane will be fine.
But EPA still won't work in a 1 servo wing either. Though you can fine tune a little with it, it's still not going to be that useful.
I think someone else previously mentioned "close enough" is good enough. You don't need the exact throws recommended, just get it close and the plane will be fine.
04-08-2005 | 03:02 PM
#22
RE: Aileron Servo
Thats why I always try to get the ratios close and then just DON"T PUSH THE DARN STICK SO FAR. Best limiter I know, of course it's harder with a beginner. How often do you really NEED to bang the stick all the way to the stops?
04-08-2005 | 03:14 PM
#23
RE: Aileron Servo
Did anyone notice that this thread is a year old? It made a sudden leap forward almost exactly a year. I didn't catch it until I saw a post dated 4/9 and thought, "today's not the ninth, is it?"
-Scott
-Scott
04-08-2005 | 03:42 PM
#24
RE: Aileron Servo
You're right, hadn't noticed. Griffin_NC has a current thread running where he is building a Corsair with retracts. Probably doesn't need any more help on this. Or as Rosane Rosana Dana would say "Never mind".
Bye all
At least we were trying.
Bye all
At least we were trying.
