Wing Dragon 4, a 4-Ch Aileron Trainer

Rick Allison

New member
I posted a request in the "Request Aircraft Here" thread for one of the more popular and affordable RTF aileron trainers, the Wing Dragon 4.

There are FMS models of the 3-channel Wing Dragon and the 4-channel Wing Dragon Sportster/Beginair, but not the WingDragon 4, which differs from both.

So I'd love to see a custom (read: free!) 4-ch pod-and-boom trainer for RF. Thanks to TomXP411 for choosing to give it a try.

Per Tom's request, I'll re-post the relevant information in this new, dedicated thread, beginning with...

Specs:

46.5" wingspan
35.5" long
341 sq. in. wing area
23 oz. flight weight
9.9 oz./sq. ft. wing loading
8 cell 9.6 volt 1000 mAh NiMH battery
Speed 480 brushed motor
7x3SF prop
CG: 2.75" aft of LE
Base Colors: Orange/Black

Possible aircraft variants for brusless, LiPo, etc.; more info than you can imagine can be found via links in a post at the R/C Universe Forums

Views are attached.
 

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TomXP411 has asked for data on the rudder, elevator, and aileron travel.

I don't have mine yet, so I can't measure them, but I found the following data in a thread at RC Groups where user "Vortex2001" gave the settings he felt made the FMS version of the 3-channel version of the Wing Dragon fly like his own:

0 1:Type(-) Type[0=Plane] ParDesigner Ver0.8
4 2:Tmax(N) Maximum Thrust
0.05 3rmax(rad) Maximun Rudder Angle
0.05 4emax(rad) Maxmim Elevator Angle
0 5amax(rad) Maximim Aileron Angle
3.0 6:CLmax(-) Maximum Lift Coefficient
-1 7:CLmin(-) Minimum Lift Coefficient
6.2 8:CLa(/rad) Lift Gradient
4.0 9:CLaSt(/rad) Lift Gradient in Stall
0.045 10:CDw(-) Drag Coefficient of Wing
0.04 11:CDb(-) Drag Coefficient of Fuselage
0.4 12:mug(-) Friction Coefficient of Wheels
0.76 13:dCDSt(-) Rise of Drag Coefficient in Stall
0 14:CM(-) Moment Coefficient
0.025 15:alpha0(rad) Wing Angle
1 16:b(m) Wing Span
0.2 17:c(m) Wing Chord
0.12 18:hce(m) Equivalent Center of Gravity
0.55 19:m(Kg) Mass
0.04 20:Izz(Kg*m^2) Yaw Inertia Moment
0.04 21:Iyy(Kg*m^2) Pitch Inertia Moment
0.002 22:Ixx(Kg*m^2) Roll Inertia Moment
0.04 23:She(m^2) Effective Area of Stab
0.03 24:Sfe(m^2) Effective Area of fin
0.6 25:Lt(m) Tail Moment Arm
0.01 26:VForm(-) Effect of Dihedral Angle​

As a newbie, I don't know if or how how that'll translate to RF. And because it's the 3-channel FMS model of the Wing Dragon, it doesn't give the aileron data. But I hope it's helpful as a start.

I'm hoping to have enough scraped together by the weekend of Feb. 9/10 to order my own WD4.
.
 
If you posted in "Request Aircraft Here" there is no reason to make another post and start a new thread. If a designer wants to make it he will look there. No need for a double post.

I see that Tom asked you to re-post this but there is no need too. Your original post was just fine.
 
From TomXP411:

wait! Did you say you have an FMS version? If you can find out who made the FMS model, I'm fully capable of translating the .X to a 3DS file. From there, it should be child's play to add controls to the mesh. (FMS doesn't have moving controls, so we'd have to cut them in from scratch.) ... And see if you can contact whoever created the FMS model. We can't re-distribute his mesh without permission.

The FMS 3-ch. Wing Dragon and Wing Dragon Sportster models can be found HERE.

I will contact the designer and seek permission for us to work with his files.

.
 
tnorton12000 said:
If you posted in "Request Aircraft Here" there is no reason to make another post and start a new thread. If a designer wants to make it he will look there. No need for a double post.

I see that Tom asked you to re-post this but there is no need too. Your original post was just fine.

I think he wanted to have a model development thread; I'm happy to delete my other posts in the Request thread if it's important to avoid duplication.
 
So here's what I found after a little bit of trial and error testing:

I started by using the existing FlyZone SkyFly. I modified the physics to resemble the description in your post.

1. I flattened the wings (except for the tip segment) and added ailerons. To make them effective, I set them to 25% and 30º
2. I increased the visual and physics size to 110%
3. I upgraded the motor to a Speed 480 and the prop to a 7x3 electric park flier.
4. I changed the battery to a 1.2v 1100mAh 8 cell pack.
5. I adjusted the CG to 0,-.32,0
6. Increased eleveator length to cover the whole hstab and set throw to 30º

Final weight: 1.22 lbs (slightly lighter than the 1.4 lbs of the Dragon 4)

As the SkyFly is very similar in configuration to the dragon, I figured it was a good palce to start. It turns out I was right. The plane has just enough thrust to pull a loop in level flight and with the trim at center, it'll fly hands off, climbing slowly at full throttle. Landings are interesting: it drops speed very quickly when you kill the throttle, so I pull a pretty steep approach.

I'm going to try to re-install G3, but it doesn't seem to work very well on this PC - lots of crashes. If I can get G3 up and running, and if I can get the Kex export utility to work, we may be able to make this go. If not, you might have to settle for adding ailerons to the SkyFly. I'll let you know soon.
 
TomXP411 said:
...

The plane has just enough thrust to pull a loop in level flight and with the trim at center, it'll fly hands off, climbing slowly at full throttle. Landings are interesting: it drops speed very quickly when you kill the throttle, so I pull a pretty steep approach.
FYI from flight reports on the WD4: The looping sounds about right. But it's a 'floaty' plane, and will glide nicely in for a landing with the throttle off.


TomXP411 said:
I'm going to try to re-install G3, but it doesn't seem to work very well on this PC - lots of crashes. If I can get G3 up and running, and if I can get the Kex export utility to work, we may be able to make this go. If not, you might have to settle for adding ailerons to the SkyFly. I'll let you know soon.
Thanks for whatever you're able to do, Tom. As a beggar, I try not to be too choosy. ;-)

.
 
There are a fair number of videos on the net showing the WD4 in action. There's a nice brief YouTube video right here that shows a WD4 taking off, turning, looping, rolling, and landing--if that helps true up flight characteristics.
 
Rick Allison said:
FYI from flight reports on the WD4: The looping sounds about right. But it's a 'floaty' plane, and will glide nicely in for a landing with the throttle off.



Thanks for whatever you're able to do, Tom. As a beggar, I try not to be too choosy. ;-)

.

I did play with the 3DS import process a little more last night. My WIP thread over on the G4 forum has the result: a fully functional (if not UV Mapped) plane, with retracts and interior. I can use the mesh on G3 or G4.

So all that's left is for me to get a stable copy of G3 running, and then I can import the model and get the physics (re) done.

The video will help... at least I'll have an idea of how aerobatic the real deal is; the only problem is I won't know how it "feels"... and that's just as important as anything else. (watched video...) I can see that my physics model needs help. My plane dips a lot more going into the turns, and while the roll rate is about the same, mine drops a lot more while rolling. Mine also will not fly inverted. I'm curious to know how much down elevator it takes to keep one of these inverted.

I probably need a different airfoil - one that's more symmetrical. I also probably need to modify the body airfoils to produce less drag - that will help the approach.

(Of course, I could be getting tripped up by being so used to full scale sims - full size planes approach at a pretty shallow angle, roughly 3º. The rule is you should be 1000' up for every 3 miles from the runway. However, it seems like RC planes, with their smaller size, tend to approach from much higher angles.)

On the visual model: If you can't get permission to re-distribute the meshes you found, then I'll update the physics on the G3 version of the SkyFly. With the changes I made in G4, it's definitely more fun to fly.

If I can't get G3 to work properly, I may send you a detailed list of settings and let you assemble the physics model (it's not that hard if you're basically just typing in the data) after importing the Kex file. We'll see how that goes. Either way, when we get done, I'm hoping to have a fully functional plane for G3 and G4.
 
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TomXP411 said:
...
The video will help... at least I'll have an idea of how aerobatic the real deal is; the only problem is I won't know how it "feels"... and that's just as important as anything else.
...

I'm curious to know how much down elevator it takes to keep one of these inverted.
From what I've read, it does take a fair amount of down elevator to fly it inverted..

As for feel: I'm going to go over to the R/C forums where this plane has been discussed and will look for R/C pilots who have a WD4 and who also use RF. Perhaps I can get them to contribute here, and you'll get some better answers for your questions about the real model.


TomXP411 said:
...
For clarification: do you have one of these, or are you trying to simulate one prior to buying, or are you just looking for something interesting to work with?
I don't have one yet, but am going to buy one--regardless of the sim model status--this weekend if I can get the $ together, which depends on selling some stuff on that auction site that will not be named.

Part of the reason I'm getting it is to help my son learn to fly 4-ch. R/C. He's getting pretty good with RF (still can't land 'em, but sure can keep 'em in the air). Anyway I'd like to have him practice with the virtual WD4 before taking on the real one.

At least one person around these forums--WilyJetGuy--wanted to fly it sim before buying, though that was a while back. Wingman57 had indicated he was going to try to put one together, but I don't see that anything came of it.


TomXP411 said:
...
If I can't get G3 to work properly, I may send you a detailed list of settings and let you assemble the physics model (it's not that hard if you're basically just typing in the data) after importing the Kex file. We'll see how that goes. Either way, when we get done, I'm hoping to have a fully functional plane for G3 and G4.

As for G3: Don't keep pounding your head against the wall beyond today or tomorrow. I'd be happy to try assembling the physics model--always happy to learn new things, and I can type. Passably.

FYI, I've e-mailed the FMS guy but have no response yet. He's in Indonesia, so a) it could be a while and b) he may not understand English well enough to know what I was asking him for. Of course, he probably knows English much better than I do Indonesian. ;-)

.
 
Hi, all. About FMS guy you talk about, Mr. Rizky aka WindRaider, is a friends of mine. As an admin of our local Aeromodelling Club here in Indonesia, and me as one of their sim moderator, here in http://gaero.info/forum/

I already get him permission to mod the models, make some 4ch Wing Dragon into FMS, actually adjustment in par file with our Club Logo here, http://gaero.info/forum/viewtopic.php?t=131

my_wdragon_in_FMS.jpg


I think you can use it x.files convert to 3ds as long you give some credit to him (WindRaider), me(DeVIN) and our forum (Grage Aeromodelling) off course.

Regards.
DeVIN, Grage Sim Moderator.
Indonesia.
 
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Sorry, here the model for FMS,..

Regards.
DeVIN, Grage Sim Moderator.
Indonesia.
 

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devindh said:
Sorry, here the model for FMS,..

Regards.
DeVIN, Grage Sim Moderator.
Indonesia.

DeVIN,

Greetings and thank you to you and to Mr. Rizky/WindRaider for permission to use the FMS Wing Dragon model he created. I believe the file you've provided is just what TomXP411 was looking for. I'm confident proper credit will be given if the model is used to develop the RealFlight version of the Wing Dragon 4.

Happy flying!

- Rick
 
Sweet!

One step closer... now all I need is free time.

Lots of free time.

:)

Thank you, DeVIN, and please relay our thanks to WindRaider.
 
TomXP411 said:
I

The video will help... at least I'll have an idea of how aerobatic the real deal is; the only problem is I won't know how it "feels"... and that's just as important as anything else. (watched video...) I can see that my physics model needs help. My plane dips a lot more going into the turns, and while the roll rate is about the

Ive been flying the Wing Dragon 4 for about 6mo. I have G3.5. Belive it or not the plane flies alot like the low wing Ryan to me(other than inverted roll over). It is floaty at low speed but dips a fair amount in high bank turns at speed. It actually flies inverted with very little elevator input but due to the high wing it wants to roll back over so you have to fly it on its back. Roll rate is about 1 per sec with about a 3 ft drop. Stall turns are good with some foward momentum required (not a true stall). Level flight loops are about 20ft diameter. The plane handels wind well for a trainer...I fly in 10mph wind with no problem. It is not as self correcting as the Nexstar due to not as much dihedral. (Cross a Nexstar and a Ryan and you may just have it :p )
 
HeadMaster said:
Ive been flying the Wing Dragon 4 for about 6mo. I have G3.5. Belive it or not the plane flies alot like the low wing Ryan to me(other than inverted roll over). It is floaty at low speed but dips a fair amount in high bank turns at speed. It actually flies inverted with very little elevator input but due to the high wing it wants to roll back over so you have to fly it on its back. Roll rate is about 1 per sec with about a 3 ft drop. Stall turns are good with some foward momentum required (not a true stall). Level flight loops are about 20ft diameter. The plane handels wind well for a trainer...I fly in 10mph wind with no problem. It is not as self correcting as the Nexstar due to not as much dihedral. (Cross a Nexstar and a Ryan and you may just have it :p )

Headmaster--thanks very much for the data! This will help us tune the model if I don't have mine in the air when TomXP411 is done...
 
Update

This is the current state of the Wing Dragon. I'm kind of low on free time right now, so I'm not sure how much I'll get to work on it.

The .tga file is included in the RFX; you can use this to create your own paint job. I posted instructions in a prior post on how to convert this to G3.5

As time allows, I'll try to work some more on this, but I think it's at the point where someone with G3 can take it and run with it. I'll also gladly send the current .3DS files to anyone who wants to take it further.
 

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