Posts by brunnerant

    Regarding the slow rolling, I think that it might be ok. I have never flown a hangglider, but I fly a paraglider, so I occasionally fly with some hanggliders. I think that the hanggliders that I have flown with had where more beginner-friendly ones. That means that they have a way smaller wingspan, which probably means that they're easier to roll (that seems intuitive to me, but I don't know if that intuition transfers to reality :-) ). Also, beginner hanggliders are lighter than other ones (since pro hanggliders have a solid leading edge, as opposed to just tubes and fabric), meaning that the pilot-to-glider ratio is higher, so when the pilot moves, it has more impact on the center of gravity of the whole system.

    Anyway, I will try to tweak the masses a little bit, to adjust the pilot-to-glider ratio, and see if that changes something. Regarding the horizontal position of the center of gravity, I will keep adjusting it until it feels stable.

    I am happy to read your post larrylynx , and to see that I am not the only one having a hard time understanding TMD files^^ (even though I have some solid geometry and math background). Maybe there should be a course "MA-101 - writing TMD files" at university :D.

    I will keep you updated about the progress that I managed to make, but don't be disappointed if it isn't soon, because I am very busy at university right now ;).


    Hello !

    I hope you're still doing fine in this weird 2020 :P. I finally had some time to work on the project, and I made some progress, so I wanted to give you some signs of life !

    I used your aerodynamic calculations, ussiowa, and they are quite good, even though there are probably some things that we could improve. Now the hangglider is flyable, and it can be controlled using only mass transfer. Here is what I have noticed, and what I should improve:

    • The computation for the CG and the MAC seem to give a pretty "tail
      heavy" behavior, where the glider has a tendency to pitch up. I have tried to move the pilot forward and it gave some better results (I moved it about 50cm forward, which is a lot!). Maybe that behavior could be coming from the aerodynamic of the wing as well.
    • The hangglider seems to roll pretty slowly (pitch is fine however). It
      takes about around 5 seconds to roll to a 45° angle with the pilot leaning to the right pretty heavily. That might be caused by the pretty big wingspan. Beginner gliders have a smaller wingspan as well, so that's maybe the reason why. And additionaly, some gliders have elevators as well, so I will try to add some elevators to see if the behavior is better.
    • I have added a vertical stabilizer to the glider (which is invisible) to prevent it from "sliding". Without that stabilizer, the glider is uncontrollable, starts turning in all sorts of directions, and it seems to be because of that "sliding". With the stabilizer, the glider is now very stable (and it could be another reason for the slow rolling).
    • Moving the pilot around makes the glider "jiggle". I added a "servoclassic" with the speed set to "2.0" to smooth out the pilot movement and try to mitigate that problem. It is better, but still present. I think this is due to how the rigid body system works, where the impulses that are applied to the bodies are causing those jerks.

    Thank you all for your responces, and sorry for the delay, I am pretty busy these days ;)...

    Yes of course it is :)

    That's some good news ;), it means that there is an error coming from my side. For now I have animated the graphics and the physics separately, so that's probably a bad pattern according to your answers. This also explains why I see the graphics moving but no behavior change. I will make sure that the graphics follow the physics, so that I can be convinced that the masses are actually moving.

    Thank you very much for your calculations, you rock !! I didn't have time to dig into your results, but I will definitely use your values to position the pilot relative to the wing.

    Again, thank you guys so much for your involvment <3


    Okay guys, some updates, since I had time to test the new airfoils that ussiowa gave me.

    First, I had to tweak the CG so that the flying is stable (like in your story, I have experimented, and I didn't rely on theory ;) ). After some tweaking, I was able to observe some stable flying behavior. However, I couldn't experiment much, since I somehow wasn't able to steer the glider.

    I hooked up the pitch and roll input from the simulator to a linear joint, and to the graphics. The graphical part works, because when I steer the glider, I actually see the pilot's graphics pitching/rolling. However, I am dubious that the linear joint is working because steering doesn't have an effect on the flying behavior... So I have to fix this...

    Does anyone know if there is a way to debug the rigidbodies while in the simulator ? I would really like to be able to verify that the pilot's rigidbody pitches/rolls when I control the plane in the simulator.

    Anyway, thank you guys for your involvment in the project !


    Hello ussiowa !

    Thank you for your message ! I don't have a lot of time those days since I am doing a master in computer science, but I try to work on the hangglider in my free time.

    I was thinking that you probably have the knowledge to help me with the dynamics of the hangglider, because I encounter some stability issues. The hangglider is stuck in a stall behaviour where it constantly rotates forward or backward, I guess that I may need to tweak the horizontal position of the pilot, so that the load on the wing is more stable. Also, I think it has to do with the fact that the initial speed of the glider is too slow, so it doesn't glide at all, but rather falls straight from the start.

    If you want to know more about that project, you can send me an email at and I will be happy to discuss in more depth about it ;).

    Thank you so much for the interest, I really appreciate !


    Thank you guys for your help, I really appreciate it !

    I have done what you said and started from a working file. I have taken the template.tmd file from the aircraft workshop, added my geometries, and added the aerowing definition from the asg29 glider. It doesn't crash anymore, which is some good progress ! However the dynamics are very unstable, so I will have to tweak it that so that the hangglider is actually flyable...

    For the flight dynamics, I thought about controlling the hangglider using weightshift, so that it is as realistic as possible. The setup I thought of is having a rigidbody (the pilot) connected below the fuselage through a linearjoint which can be actuated by the player. I am not sure whether this is going to work, since nobody really did that before. Anyway, I will experiment, and who knows, maybe it's gonna work.

    I attached some screenshots of my model (to tease you :P), which I am very proud of. I have made it myself using Blender and GIMP, but I haven't added specular and reflection maps yet.

    I will keep you updated if I manage to make some progress. Cheers !



    First, let me tell you that an actual issue was that I was putting an empty line at the beginning of the TMD file, causing the aircraft converter to crash... The parser for the TMD file is definitely very brittle (and not talkative, which is even worse for the aircraft developers, but anyway, let's not get distracted). But unfortunately, once one error is solved the next stupid error shows up (that seems to be a constant in the world of computer science).

    Here is the minimal TMD file that I am trying to get through :

    Now, when I use the aircraft converter, I get an "unreferenced geometry Wing, SpeedBar, Cables and Keel", even though they're referenced in the TMD file, so I don't understand the problem here. When I open it in FS2, the preview is empty, and the game freezes during the loading screen.

    I really have no idea why all those things happen to me, even though I have read all the documentation very carefully, and several times... I feel very stupid now, because this aircraft converter has driven me crazy ;)...



    Thank you so much for your help !

    I will look into your suggestions and in case it really doesn't work I can post the full TMD file. Note that in the excerpt I posted, I have purposedly omitted the "<[file][][]>" and "<[modelmanager][][]>" tags.



    It is very weird, it still doesn't work... I have commented everything in my TMD file, except for the following :

    I had to keep the telemetry section, because for some unknown reason, removing it makes the simulator crash at startup... As you can see, there is only one rigid body, and no joints, so I don't see what could be the problem here. But still, the simulator freezes and I cannot move the mouse cursor anymore.

    I am really helpless right now, and I am starting to question whether I am extremely stupid or not...

    Ok, I will definitely look into that, thank you for the insight !

    Some of my rigid bodies overlap, but that's fine, according to the tutorial. Maybe it has to do with some incorrect joints, as you say, so I will try to search.


    Again, I encounter some problems in the development of my custom aircraft. I have a 3D model which is comfortably in the poly-count limits (around 35K faces). However, when I open it in the simulator, it is incredibly laggy... I have found out that the reflections are costly, so I have disabled the reflections alltogether in the 3D model, but it still doesn't solve the issue. Also, the TMD file of the aircraft is still pretty simple, and I don't see why this would be the cause...

    If anyone knows what could be the source of the lag, I would appreciate ;).

    Happy flying !

    Antoine Brunner


    I am making progress making my own hangglider model in Aerofly. However, I find it more and more difficult to debug errors because of the lack of documentation about the aircraft SDK. The begginning is very well guided by the tutorials, but as I move into the controls, and the comunnication between dynamics and graphics, it is harder and harder to make progress.

    Is there any full documentation of the aircraft SDK ? If so, could you point me to it ? The tutorials are great, but some sections are missing, which makes it hard to know the full capabilities of the SDK.

    Thank you very much for your help !



    I am currently creating a hangglider model for Aerofly FS 2. Since I am not a 3d designer at all, I downloaded a free-to-use 3d model of a hangglider to work with. The problem is that it doesn't have square power-of-two-sized textures, so the aircraft converter won't work with that.

    After some research, I found that ProxyTextures is a 3ds max plugin that can resize textures to the nearest power of two. However, it doesn't allow me to make the textures square, so I am still stuck at that point.

    Does anyone know a way to "squarify" the textures in a 3ds max scene ?

    Thank you for your help,


    Is the texture in the correct format, I always use a BMP and perhaps the most obvious, is that texture in the intermediate folder


    Thank you for your answer !

    The textures are in PNG format. According to the documentation, this is supported, right ? They're all located in the folder where the TMC and TMD files (that's what you call the intermediate folder, if I understood right).


    I am currently creating a new plane for Aerofly FS 2. I read the documentation about converting an aircraft and followed the different tutorials that are available (those are great, by the way !). However, when I convert the 3D model that I have exported in the tgi format, the aircraft converter is stuck saying "loading texture xxx".

    This is not a big deal. The only real problem is that I couldn't find any explanation of why it doesn't work in the log files (both in the aircraft converter directory, and in the aircarft directory). This means I cannot work on solving the problem, since I don't actually know where the problem is.

    Does anyone has an idea of why the aircraft converter would be stuck loading textures ? If not, could you at least tell me where I can find more debugging information about the conversion errors ?

    Thank you for your help, cheers !

    Antoine Brunner