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Old Feb 11, 2007, 08:50 AM
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Worth adding Ailerons?

I have a Windstar EP glider by Thunder Tiger, and dislike having only elevator and rudder controls. I would like to add ailerons. Considered using HS-55 servos on the outboard panels, with ailerons on the trailing edge of the outboards. Perhaps looking like an older or vitage wing. Good idea, or Bad? And why or why not, advantages, disadvantages? Thanks.
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Old Feb 11, 2007, 01:03 PM
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Quote:
Originally Posted by Wing Zero
I have a Windstar EP glider by Thunder Tiger, and dislike having only elevator and rudder controls. I would like to add ailerons. Considered using HS-55 servos on the outboard panels, with ailerons on the trailing edge of the outboards. Perhaps looking like an older or vitage wing. Good idea, or Bad? And why or why not, advantages, disadvantages? Thanks.
EP is heavy to begin with. Adding ailerons with servos to the wing tips would not be an improvement. My suggestion would be to learn as much as you can with your Windstar, while building the ship of your dreams for the future.
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Old Feb 11, 2007, 01:14 PM
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Ailerons.

Hello Wingzero.

Ailerons on a sailplabe : There ought to be a Unite Nations Ban on sailplane models WITHOUT aillerons !!

Your Idea is quite usable and wil give you experience in altering a plane to another config.

As Histarter writes you might consider a new plane with a higher performance.

You might benefit if you look deeply into :

www.gliders.dk
www.f3j.dk

May you have luck with your work.

KR

hld - OY-9901.
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Old Feb 11, 2007, 03:49 PM
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Originally Posted by Hans Dahl Christ
Hello Wingzero.

Ailerons on a sailplabe : There ought to be a Unite Nations Ban on sailplane models WITHOUT aillerons !!

Your Idea is quite usable and wil give you experience in altering a plane to another config.

As Histarter writes you might consider a new plane with a higher performance.

You might benefit if you look deeply into :

www.gliders.dk
www.f3j.dk

May you have luck with your work.

KR

hld - OY-9901.
There are airspeed concerns with ailerons.
Because added weight your EP will fly a bit faster, however to work low lift, one needs the slow airspeed of higher alpha, and this situation is catered best with poly (i.e. no high alpha control reversal).
Floating is partisan to Poly; whereas, if one is more dedicated to cruise speeds, ailerons are favored.
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Old Feb 12, 2007, 06:12 AM
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A wing designed to fly well in an R/E configuration will usually not work well with ailerons.
Buy yourself an aileron wing kit from a different model that will fit on that fuselage, if you like, but you won't be happy converting the wing you have..
..a
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Old Feb 14, 2007, 10:50 PM
SlingWinger
San Bernardino, California, United States
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Ailerons,schmailerons. Just increase the dihedral and add rudder effectiveness. Use 1/8" sheet foam to add 1" extra width to the rudder.
Extending this foam piece to increase height and have some area fwd of the hinge line is even better.
The easiest way to add dihedral to an all ready built plane is to use
sheet foam (meat trays work well) and make winglets that can be easily taped on to the wingtips. I use masking tape as it is easily removed at the end of the day.
My first rc was a Hobie Hawk, in fact my first half dozen rc's were Hobies. It wasn't 'til 1980 that I ever flew anything else, and boy was I surprised to find that most fliers thought the control authority found on a stock Gentle Lady, Oly, or Spirit etc. was adequate. Since I can no longer afford Hobies I've learned how to make most any R/E glider jump when I say Frog. Wish I had a nickle for all the times I bought R/E gliders from some one dirt cheap because they thought ailerons were needed to get a quick roll rate. Ailerons are more efficient because you're not skidding the fuse, creating drag, but at really low "floater" speeds remember that skidding a dihedral/polyhedral
wing makes the whole wing an aileron, not just a piece of the trailing edge. If you understand how a thing works you won't have any trouble figuring out how to make it do what you want.
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Old Feb 15, 2007, 02:18 AM
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If it has spoilers, add dual micro servos and make spoilerons. They are fairly effective at all speeds and you still retain the RES status if you need to by making turning off the spoileron functions. As for bare R/E, you might as well fly a freeflight plane. They are great to learn on, but ailerons are the way to go. Control reversal does not happen in unpowered airplanes. There is no propstream to keep the inboard section flying with a stalled outboard. Besides... doing rolling circles while thermaling is kinda fun. Try that with a poly plane!
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Old Feb 15, 2007, 09:33 AM
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Originally Posted by threcixty
If it has spoilers, add dual micro servos and make spoilerons. They are fairly effective at all speeds and you still retain the RES status if you need to by making turning off the spoileron functions. As for bare R/E, you might as well fly a freeflight plane. They are great to learn on, but ailerons are the way to go. Control reversal does not happen in unpowered airplanes. There is no propstream to keep the inboard section flying with a stalled outboard. Besides... doing rolling circles while thermaling is kinda fun. Try that with a poly plane!
Dayhead, you are right on my friend, however with mixed aileron and rudder you have almost the same situation as poly - as far as losses are concerned. Both situations require a bit of forward slip to accomplish the spiral program.

Threcity, servo reversal is airspeed oriented. Light weight (floater) sailplanes flying low airspeed will demonstrate a lifting wing tip and total lack of turn authority - as demonstrated with my experiments with turbulation (that could force controlled high alpha low speed flight). [More delta D than delta L]
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Old Feb 15, 2007, 08:10 PM
SlingWinger
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This hobby is all about the adventure of discovery. I think you would enjoy the whole process of modifying your glider by adding ailerons. The glider in it's stock configuration uses what is called yaw-roll coupling to reach a desired bank angle. When the rudder is angled the glider goes into a skid, the dihedral (polyhedral is just another form of dihedral) causes the wing to have a differential angle of attack- more on one side and less on the other. This results in a rolling moment and you get a bank angle, or a complete roll if the rudder is kept deflected. You say you are dissatisfied with the gliders control mechanism, and I am not surprised as most of these designs don't respond quickly to roll input. I flew a Windstar a few years ago, but knowing what it would be like handling-wise ahead of time due to most of my 30 years of rc gliding, mostly with R/E type gliders, I modified mine by adding rudder area and winglets to the wingtip. This is by far the easiest way but adding ailerons will work also. Keep in mind that deflecting the ailerons alone will create an adverse yaw that, when coupled with the dihedral,will actually try to roll the glider the wrong way, so the roll rate will be slow unless you input PLENTY of rudder at the same time you input aileron. This is why you should plan ahead when configuring the geometry of the servo-to-aileron connection so that a good amount of aileron differential will be present. On this particular glider I wouldn't be surprised to find that up-aileron travel should be almost twice that of the down-aileron travel. This will help reduce the amount of rudder input needed to counteract the aileron-induced adverse yaw. Another thing to check into is the possibiliy of electronic troubles due to the long wires required to reach the wing-mounted servos. It's my understanding that these long wires can act as an antenna, and that they should be twisted some minimal amount per unit of length. They will also have more resistance to electron flow so it might be necessary to go to a 5 cell rx battery pack (6 volt). Check with the guys in the electronic forums for help with this. So I think you can see what you're up against here. Nothing too difficult,really, and you will have fun and can take pride in having a "Customized" arf. I prefer the simple aerodynamic mods myself, but then again I'm a lazy cheap-skate.
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Old Feb 15, 2007, 08:15 PM
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Quote:
Originally Posted by histarter
Threcity, servo reversal is airspeed oriented. Light weight (floater) sailplanes flying low airspeed will demonstrate a lifting wing tip and total lack of turn authority - as demonstrated with my experiments with turbulation (that could force controlled high alpha low speed flight). [More delta D than delta L]
I can see where you are coming from, but with the right aileron differential, i.e. not much down aileron for the upmoving wing, control reversal doesn't happen. It cannot without addition of a stall or atleast a huge seperation moving up from the trailing edge. Aileron gliders can and do perform better at slow speed then poly gliders IF they are light and utilize an airfoil for the cause. Also, extending ailerons to the tip can cause an earlier tipstall (control reversal) because of the increased camber and flow turning on the upmoving wing. It surprises me that the Supra has this in its design. I love poly planes, and they will roll just fine with enough control surface on the rudder. Also, keeping the tips very light makes them roll much better without much yaw before roll. Also, high alpha flight in an unpowered aircraft results in an incredible increase in induced drag, and sinkrate. Sorry, but your control reversal observations seem to be from a very unlikely situation that will not happen unless most of the tip is stalled. Ailerons are better.. More fun also!
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Old Feb 15, 2007, 09:32 PM
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Originally Posted by threcixty
I can see where you are coming from, but with the right aileron differential, i.e. not much down aileron for the upmoving wing, control reversal doesn't happen. It cannot without addition of a stall or atleast a huge seperation moving up from the trailing edge. Aileron gliders can and do perform better at slow speed then poly gliders IF they are light and utilize an airfoil for the cause. Also, extending ailerons to the tip can cause an earlier tipstall (control reversal) because of the increased camber and flow turning on the upmoving wing. It surprises me that the Supra has this in its design. I love poly planes, and they will roll just fine with enough control surface on the rudder. Also, keeping the tips very light makes them roll much better without much yaw before roll. Also, high alpha flight in an unpowered aircraft results in an incredible increase in induced drag, and sinkrate. Sorry, but your control reversal observations seem to be from a very unlikely situation that will not happen unless most of the tip is stalled. Ailerons are better.. More fun also!
I love ailerons on an Ellipse that has a RG-15 and has about an 11 to 1 AR. Launch it high with about 10 oz ballast; it was a dream come true. Differential ailerons, crow for landing, 50 degree flap, mixed flap and elevator, mixed aileron and rudder. However flying it empty with turbulators (used to extend slow flight for short launching) that is better regulated, even with more up aileron then down, she was almost as gamey as a Legionair set up similar with flaps and ailerons. The Legionair's 15 to 1 AR probably aggravated the situation; plus the fact the loading was less for even slower airspeed.

I have yet to see a 24 ounce 2 mtr aileron floater out thermal a lighter correctly set up poly machine. Now set up both machines at 7 oz per foot plus, and ailerons will have an advantage (especially if poly is not maximized for the airspeed increase). I have enjoyed watching Brian Agnew fly his 11 oz/ft 2mtr, and beat out my 8 oz/ft GL with poly in competition, but that was because he was a much better pilot! Switch aircraft and he would still beat me - probably by a bigger margin!
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Old Feb 16, 2007, 02:03 AM
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You flew with Brian... was he flying a Banshee by any chance?? Don't get me wrong.. There is a time and a place for poly planes. Mainly RES comp and the 80's There have been days where the thermals were smooth and did not try to invert my glider every 2 seconds. There werent many of them. A poly ship will do wonders here. The problems with poly planes are this:
1. They are statically and dynamically stable, and will try to return to level flight when upset. This is great for a beginner, as hands off flight AND righting when upset keeps people out of trouble. The problem with this is that turning in a thermal requires a surface or two to be deflected to maintain the turn. This and the fact that a poly plane needs to be in a slip to make it stay in the turn create a lot of drag. Most aileron planes will hold a turn better without as much control surface deflection. When you do need to deflect a surface, an aileron is much more efficient at initiating a turn then a rudder IF it is used correctly. I am not talking about people that mix in rudder on the aileron stick. Close to the ground in light lift, with two identical airframes, one with ailerons and one poly, the aileron plane will outperform and out maneuver the poly plane every time. Most people seem to use ailerons ineffectively by using large deflections and a lot of them. This will undo the advantage. As to the original question in the thread, Why not make yourself a straight wing and put ailerons on that? I am sure that someone in your club/hobby shop has a foam cutter. Add some 3m77, some balsa, mix well and serve. Also, back to the spoilerons. They work very well and are easy to add to a plane like yours. It would take you about an hour and cost less then $30 including the servos. Good luck!
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Old Feb 16, 2007, 02:07 AM
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forgot to add.. Why trip a RG15? Just wondering. E387, maybe. E205.. I never found it to do anything other then look cool. An RG15 is pretty similar to a 205, just wondering if it helped it or not.
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Old Feb 16, 2007, 11:17 AM
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forgot to add.. Why trip a RG15? Just wondering. E387, maybe. E205.. I never found it to do anything other then look cool. An RG15 is pretty similar to a 205, just wondering if it helped it or not.
Banshee is correct for Brian.

RG-15 was too slick for low launch scoring. The turbulator slowed her down a bit for improvement, but it still could not compete with a Mirage (poly) at 7 oz/ft - when launch was below 400 feet. This experiment was flown with 3 different pilots at the time making statistical records to establish conclusions. Now launchings above 400 feet (where statistics do not work for establishing reliability of a fixed soaring factor task) the superiority of the Ellipse was totally obvious! The Ellipse was typically the last bird down.

Only one small flaw in your aileron argument, and that is a pilot is not aboard the model* so a coordinated turn is impossible. Mixing ailerons with rudder sets the machine back toward poly, where the inboard slip to maintain a spiral is still a mathematical necessity!

*[One can build in a 'pilot' through programming a small computer - using a few modern sensors]

Footnote: And the turbulator for the E205 worked to fix the missing low end, turning the Saggita into a floater when needed. Seemed to be invisable when doing speed runs... My turbs are at least 0.032 thick.

PS Static and stable gives us slow thinkers time to look around and plot strategy i.e. act like a pilot! I realize I am showing my age here.....
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Old Feb 16, 2007, 01:41 PM
SlingWinger
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While I agree that the aileron version may at times be more efficient, I really think we are splitting hairs here. I just don't agree with the attitude shown towards the newbie who shows up at your local site, or this international virtual site,with his new pride and joy R/E glider only to be told that he made a poor choice of design and that gliders without ailerons should be "banned", for crying out loud.
Saying something like that is not only discouraging to the newbie but also publicly displays your own ignorance of the mechanics of flight control and stability. Honestly guys,it will only take a half hour of your time to make the mods to a R/E glider that I discussed earlier and prove to yourselves that that R/E IS a viable means of controlling an rc glider. Over the years I've amazed more than a few slopeheads with the roll rate,response time, and aerobatic capability of Oly's, Spirit's, GL's and the like with the simple mods outlined earlier. The fact is that the polyhedral glider is simpler to build and easier to stay oriented on in the air than the flat wingers. The Hobie Hawk proves me correct. Why the designers have continued to push these sluggish handling gliders is beyond me. If over-control by a newbie is the issue all ya gotta do is reduce the throws until they get some experience. Over the years I'll bet we've lost a lot of potential glider guiders because their first experience away from the powered scene convinced them that gliders weren't any fun. My first few gliders were Hobies and when I first tried something else (about 1980) I was literally flabbergasted that anyone would even bother flying something so sluggish and boring. Thanx for the opportunity to rant and get this off my chest. The arrogance displayed, rather than the helpful guidance that could be offered to the newcomer, just sticks in my craw.
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