4 aileron servos on GP Super Stearman
12-10-2010, 12:22 PM
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4 aileron servos on GP Super Stearman
I just picked up a GP Super Stearman from a flying buddy, and I noticed it was built with a servo on each aileron, top and bottom. The instructions call for a connecting rod from the lower to the upper aileron, but the builder decided to do it this way. Has anyone else done this? I am considering hooking the top wing ailerons to seperate channels, and with the proper mixing, use them as ailerons and flaps. What do you guys think? Do you think they will work as flaps. I realize the only way to truly know is to try it and see.....I was just hoping that some of you guys had tried it, and could advise me. Thanks in advance for your help.
12-10-2010, 12:54 PM
#2
RE: 4 aileron servos on GP Super Stearman
I hate to break it to you, but it's a really bad idea.
Being that the ailerons are outboard on the wing, this will cause the wing tips to stall first. If that happens, the plane will fall out of the sky faster than you can react to it.
Being that the ailerons are outboard on the wing, this will cause the wing tips to stall first. If that happens, the plane will fall out of the sky faster than you can react to it.
12-10-2010, 12:59 PM
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RE: 4 aileron servos on GP Super Stearman
I kinda figured that might be the case, but needed to hear it from someone else. I'm at a loss as to why the guy built it this way. I really don't see an advantage to building it this way.
12-10-2010, 01:26 PM
#4
RE: 4 aileron servos on GP Super Stearman
Actually it's a very good way to do it. By using a pushrod between the two surfaces, you don't get the correct movement due to the geometry of the pushrods, control horns and the uneven angle of the two wings.
12-10-2010, 01:38 PM
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RE: 4 aileron servos on GP Super Stearman
What Minnflyer was responding to, is your idea to use the now separated ailerons as flaps... A bad idea on a biplane!
However having individual servos that are WELL sync'd to get identical movement out of each pair of ailerons is a VERY GOOD idea if you can implement it.
So four servos are OK... provided they actually work in paired unison.
However having individual servos that are WELL sync'd to get identical movement out of each pair of ailerons is a VERY GOOD idea if you can implement it.
So four servos are OK... provided they actually work in paired unison.
12-10-2010, 02:37 PM
#6
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RE: 4 aileron servos on GP Super Stearman
There actually is a fairly easy way to use pushrods and get equal aileron deflection.
If that's what you wind up deciding to do, that is.
A picture is worth a thousand words, and I've already used that many trying to explain how simple the solution can be... and why the usual connection method is so flawed.... and what it actually does if you go along with the ARF mfgs and use their hardware as they suggest.
If that's what you wind up deciding to do, that is.
A picture is worth a thousand words, and I've already used that many trying to explain how simple the solution can be... and why the usual connection method is so flawed.... and what it actually does if you go along with the ARF mfgs and use their hardware as they suggest.
12-10-2010, 04:29 PM
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RE: 4 aileron servos on GP Super Stearman
How would you hook them up.....a pair of Y's using two channels, or 4 separate channels(assuming I've got enough open channels)?
12-10-2010, 07:16 PM
#9
RE: 4 aileron servos on GP Super Stearman
I just used the pushrods. Cheaper than y cables and works just fine on the Stearman. It's not supersonic, or 3 D. Just a nice flyer. Make sure to keep some power on when you're landing.
12-11-2010, 01:28 AM
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RE: 4 aileron servos on GP Super Stearman
ORIGINAL: MinnFlyer
By using a pushrod between the two surfaces, you don't get the correct movement due to the geometry of the pushrods, control horns and the uneven angle of the two wings.
By using a pushrod between the two surfaces, you don't get the correct movement due to the geometry of the pushrods, control horns and the uneven angle of the two wings.
thanks
V.
12-11-2010, 04:07 AM
#11
RE: 4 aileron servos on GP Super Stearman
ORIGINAL: vasek
Hi, what is the problem (in practical therms) with having a slight differential in deflection of the top & bottom (wing) aileron?
thanks
V.
ORIGINAL: MinnFlyer
By using a pushrod between the two surfaces, you don't get the correct movement due to the geometry of the pushrods, control horns and the uneven angle of the two wings.
By using a pushrod between the two surfaces, you don't get the correct movement due to the geometry of the pushrods, control horns and the uneven angle of the two wings.
thanks
V.
It may just be me, but I've experienced no problems with the differentiation of deflection between the top and bottom ailerons. My Super Stearman flies just fine with this setup.
12-11-2010, 05:10 AM
#12
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RE: 4 aileron servos on GP Super Stearman
ORIGINAL: vasek
Hi, what is the problem (in practical therms) with having a slight differential in deflection of the top & bottom (wing) aileron?
thanks
V.
Hi, what is the problem (in practical therms) with having a slight differential in deflection of the top & bottom (wing) aileron?
thanks
V.
There really isn't any problem for most model airplanes. At least not any more of a problem than having the CG a bit off, or a little warp in the wing that we trim with aileron and ignore, or a stab that epoxied in at an angle. Look over all the weekend warriors at the flying field next Saturday, you'll see lots of airplanes that don't have a problem... but do.
Problems like the differential won't be noticed by most flyers flying like most flyers do.
Want some perspective? A buddy has an Ultimate like mine except his has the mfg's rigging. The other day, he had another airplane out that he'd just put very expensive servos in. They were about .03 seconds faster and gave maybe 15% more torque. He was overjoyed at the improvements he thought he was getting. If he could fly without crashing every couple of weeks, I'd let him fly my Ultimate and see if he noticed the difference in our two Ultimates.
12-11-2010, 05:15 AM
#13
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RE: 4 aileron servos on GP Super Stearman
There is a slight problem with explaining what differences you will see. There is the accuracy a model exhibits in the flight envelope and the problems that happen during things like landing.
Slight warps and aileron differentials obviously make models less accurate in flight, otherwise we wouldn't be advised to make our split elevator halves deflect exactly the same side to side, or iron warps out of wings, etc.
Then we have a different part of the envelope, landing and taking off. The downgoing aileron that's doing 26degrees when two others are doing 20 and the 4th is doing 24degrees is going to be a possible problem. It has a better probability of stalling before the other 3. Do you want that, or even the possibility of it? Especially when you can simply install the provided hardware differently and have a "straighter" airplane?
Problems like the differential won't be noticed by most flyers flying like most flyers do.
Sometimes they aren't IDENTIFIED as being the cause of a problem that is noticed by most flyers..... snap on takeoff is one. snap on landing another. (Would they have happened if the ailerons didn't have one moving more than the rest?)
Slight warps and aileron differentials obviously make models less accurate in flight, otherwise we wouldn't be advised to make our split elevator halves deflect exactly the same side to side, or iron warps out of wings, etc.
Then we have a different part of the envelope, landing and taking off. The downgoing aileron that's doing 26degrees when two others are doing 20 and the 4th is doing 24degrees is going to be a possible problem. It has a better probability of stalling before the other 3. Do you want that, or even the possibility of it? Especially when you can simply install the provided hardware differently and have a "straighter" airplane?
Problems like the differential won't be noticed by most flyers flying like most flyers do.
Sometimes they aren't IDENTIFIED as being the cause of a problem that is noticed by most flyers..... snap on takeoff is one. snap on landing another. (Would they have happened if the ailerons didn't have one moving more than the rest?)
12-11-2010, 01:36 PM
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RE: 4 aileron servos on GP Super Stearman
ORIGINAL: da Rock
There is a slight problem with explaining what differences you will see. There is the accuracy a model exhibits in the flight envelope and the problems that happen during things like landing.
Slight warps and aileron differentials obviously make models less accurate in flight, otherwise we wouldn't be advised to make our split elevator halves deflect exactly the same side to side, or iron warps out of wings, etc.
Then we have a different part of the envelope, landing and taking off. The downgoing aileron that's doing 26degrees when two others are doing 20 and the 4th is doing 24degrees is going to be a possible problem. It has a better probability of stalling before the other 3. Do you want that, or even the possibility of it? Especially when you can simply install the provided hardware differently and have a ''straighter'' airplane?
Problems like the differential won't be noticed by most flyers flying like most flyers do.
Sometimes they aren't IDENTIFIED as being the cause of a problem that is noticed by most flyers..... snap on takeoff is one. snap on landing another. (Would they have happened if the ailerons didn't have one moving more than the rest?)
There is a slight problem with explaining what differences you will see. There is the accuracy a model exhibits in the flight envelope and the problems that happen during things like landing.
Slight warps and aileron differentials obviously make models less accurate in flight, otherwise we wouldn't be advised to make our split elevator halves deflect exactly the same side to side, or iron warps out of wings, etc.
Then we have a different part of the envelope, landing and taking off. The downgoing aileron that's doing 26degrees when two others are doing 20 and the 4th is doing 24degrees is going to be a possible problem. It has a better probability of stalling before the other 3. Do you want that, or even the possibility of it? Especially when you can simply install the provided hardware differently and have a ''straighter'' airplane?
Problems like the differential won't be noticed by most flyers flying like most flyers do.
Sometimes they aren't IDENTIFIED as being the cause of a problem that is noticed by most flyers..... snap on takeoff is one. snap on landing another. (Would they have happened if the ailerons didn't have one moving more than the rest?)
This is the best example I've ever seen of someone trying to make a point where there is none.
12-11-2010, 03:47 PM
#15
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RE: 4 aileron servos on GP Super Stearman
To make it simpler for you.........
If you have experience, yes you can probably tell the difference.
Also, it won't matter that a biplane with no differential is safer on takeoff or landing because you won't be making the mistakes that lead to that.
Or to put another way in hopes it's more understandble for you.........
If you don't have the skill or experience, you won't notice one way or the other.
Also, your takeoff and landing mistakes are going to happen no matter how your biplane is rigged.
Simple enough?
If you have experience, yes you can probably tell the difference.
Also, it won't matter that a biplane with no differential is safer on takeoff or landing because you won't be making the mistakes that lead to that.
Or to put another way in hopes it's more understandble for you.........
If you don't have the skill or experience, you won't notice one way or the other.
Also, your takeoff and landing mistakes are going to happen no matter how your biplane is rigged.
Simple enough?
12-11-2010, 08:40 PM
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RE: 4 aileron servos on GP Super Stearman
ORIGINAL: da Rock
To make it simpler for you.........
If you have experience, yes you can probably tell the difference.
Also, it won't matter that a biplane with no differential is safer on takeoff or landing because you won't be making the mistakes that lead to that.
Or to put another way in hopes it's more understandble for you.........
If you don't have the skill or experience, you won't notice one way or the other.
Also, your takeoff and landing mistakes are going to happen no matter how your biplane is rigged.
Simple enough?
To make it simpler for you.........
If you have experience, yes you can probably tell the difference.
Also, it won't matter that a biplane with no differential is safer on takeoff or landing because you won't be making the mistakes that lead to that.
Or to put another way in hopes it's more understandble for you.........
If you don't have the skill or experience, you won't notice one way or the other.
Also, your takeoff and landing mistakes are going to happen no matter how your biplane is rigged.
Simple enough?
Go ahead and delete..this is not appropriate
12-11-2010, 09:14 PM
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RE: 4 aileron servos on GP Super Stearman
ORIGINAL: WCB
and you are a moderator? You are a joke. Must not take much to qualify as a'' moderator.''..political appointment?
Go ahead and delete..this is not appropriate
ORIGINAL: da Rock
To make it simpler for you.........
If you have experience, yes you can probably tell the difference.
Also, it won't matter that a biplane with no differential is safer on takeoff or landing because you won't be making the mistakes that lead to that.
Or to put another way in hopes it's more understandble for you.........
If you don't have the skill or experience, you won't notice one way or the other.
Also, your takeoff and landing mistakes are going to happen no matter how your biplane is rigged.
Simple enough?
To make it simpler for you.........
If you have experience, yes you can probably tell the difference.
Also, it won't matter that a biplane with no differential is safer on takeoff or landing because you won't be making the mistakes that lead to that.
Or to put another way in hopes it's more understandble for you.........
If you don't have the skill or experience, you won't notice one way or the other.
Also, your takeoff and landing mistakes are going to happen no matter how your biplane is rigged.
Simple enough?
Go ahead and delete..this is not appropriate
12-11-2010, 09:37 PM
#19
RE: 4 aileron servos on GP Super Stearman
Note to WCB:
You insult a moderator and then wonder why your post got deleted?
Do you argue when a cop pulls you over for speeding too?
FYI, *I* deleted your posts, not da Rock. And I suggest you be a little more respectful.
You insult a moderator and then wonder why your post got deleted?
Do you argue when a cop pulls you over for speeding too?
FYI, *I* deleted your posts, not da Rock. And I suggest you be a little more respectful.
12-12-2010, 07:28 AM
#20
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RE: 4 aileron servos on GP Super Stearman
I actually loved my Stearman and its 2 servo set-up. I wish they would redesign it so, you had a removable hatch on top of the fuselage. My personal habit is to check all internal connections after 3 or 4 flights (OCD?). This got pretty aggravating at the field always taking it apart just to check on everything. Anyway, I plan on installing two servos in my Kangke Waco when I get around to finishing it. They recomend 4 servos but, state that it can be done with 2. A few people have built it with 2 and built the slave rod between. My Stearman's set-up made me feel that the 2 servos would be perfect for the Waco as well. Just my .02
