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FSX:SE Help Please with prop animation

Hi guys
I am delving into aircraft conversion from FS9 to FSX and also P3D to FSX. So far all is going well except for the prop conversions. There is so much information out there that I have a brain ache.
Can anyone point me to a simple explanation that will help me with this. I understand the texture and alpha issues so they do not need to be explained. It is mainly just getting the props to spin at the right speeds that is doing my head. I have tried to read Toms "TUTORIAL TO CONVERT FS2004 AIRCRAFT TO FSX (AND LATER SIMS) USING MODELCONVERTERX" but I just get lost among the techno for MCX. I do have a reasonable grip on MCX and once explained, perhaps with pictures, I can usually grasp a technique.

Grateful for any help or suggestions.



Resource contributor
There is so much information out there that I have a brain ache.
OMG, so true! Imagine actually making them in the first place! But don't strain yourself!

It is getting to the point, however, that if converting and leveraging and simulating were any simpler, someone could just say, "Siri make me a Cirrus Vision that works in P3Dv5 and MSFS, purple iridescence, please."

Which would probably be better than developers that wrote software for Prepar3d wondering why someone needs to convert their product to FSX.
I doubt you'll find a simpler explanation than Tom's tutorial. Chapter 2 on Saving and Animating The Props takes you through the process step by step. If you follow that exactly, then in my experience it should work in most cases. Perhaps if you have problem with a particular step then you could post a more specific question ? Tom is on here most days (I think) and is very helpful.

BTW this assumes you are doing a straight FS9 to FSX conversion. If you're doing more than that e.g. changing the speed of the props, then I don't believe that is covered in the tutorial. But in any case you should do the conversion first.


Resource contributor
There is no way to change the speed of the props nor to change when they switch models - that's hard coded into FS. But you can change the animation speed in the sim by adding the following line in the plane's aircraft.cfg file (into each fltsim livery section):


I have seen values from 0.9, 0.99, to 1.46 - depending on the aircraft.
Thanks for the responses guys.
Tom I have read that FSX does not use this command line and that is was used by FS2002/2004. Is this the case??
My problem is that I have an AI dornier a/c (freeware) that functions perfectly as an FS9 model in FSX but when I convert it, with no errors indicated by MCX, the props appear to rotate at a much slower RPM. I have changed the prop textures but to no avail. I am also experiencing this with an AI C130E, made by Fernando Martinez, but I think that may purely be a texture issue.
I have attached the Dorniers *.MDL files, Aircraft.CFG and a set of texture files. I wonder if it will present the same to you?
Incidentally, I am unable to find a FSX model on line for this aircraft.



  • Aircraft.rar
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Resource contributor
I loaded the model into MCX. There are 14 prop parts, all of which are assigned to prop0_still or prop1_still. Only 4 have geometry, the other 10 are invisible. None have any Visibility conditions, so they are visible all the time.

If the only prop parts you have are prop still parts, then you will never get the correct animation. There must also be prop slow and prop blurred parts, and they must have the correct visibility conditions so they switch from one to the other.
Thanks for the quick reply Tom.
I will try another go with your conversion instructions and see how I go.
Regarding my question: Is prop_anim_ratio still used in FSX, I have found many conflicting answers, are you able to answer this for me also?
Hi Tom,
I've gone through your instructions meticulously this time, I think :) , but I still have the issue. Are you able to take another look for me please to see if I have made mistakes?
If I cant resolve it I'll simply use the FS9 model this time.


  • AI Do228-200.rar
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Resource contributor

My instructions are for flyable aircraft with no LOD models. Your model is an AI model with many LODs. When you do the Merge step with an AI model you must specify the LOD model you want to add them to. You left that box at the default 100 and thus the blurred props you merged became the LOD 100 model, when your plane has 260 and 130 LOD models as the two most complex ones (and the ones that blurred and slow props should be added to at the least) . You have to do the Merge step for each LOD model you want to add them to, specifying the model each time.

Hope this helps,
Thanks again for the reply Tom.
Just so I have it right: I need to load each LOD version of the original model and then merge the slow and blurred with each of these?
I assume an export and save after each LOD merge?
Thanks so much for your patience and replies, hopefully I'll get it right eventually :) .

That's really interesting. I've converted many FS9 a/c to FSX for AI, but they've all been flyable models, so only LOD 100. I suspect had I tried to convert a FS9 AI model I might well have tripped over the same problem as Andrew. Might be worth adding a note to your tutorial, Tom ?


Resource contributor

Good idea, I will do that. But there may be other things you need to do as well, so I already direct people to AI web sites for further information.

Andrew, no, you do not load each version. If you load the plane into MCX, you will find an LOD drop down box to the right of the animation slider. That is what you use to select the "current" LOD model.

But merging does not care which model you have as "current", since you specify that in the Merge dialog box. So the work flow is nothing more than:

1. Load the model into MCX and use the LOD drop down box to determine the LOD models you want to add props to. Keep in mind the smaller numbers are only used further away and blurred props may not be visible then. You can always test this in the sim later, if you like. Keep in mind that blurred props don't have many polygons so it's not really critical.
2. Choose Merge.
3. Specify the LOD model you want to add the props to and merge the props as usual.
4. Repeat steps 2 and 3 for each model you want to add props to.
5. Continue with your conversion.
Thanks Tom

I have made progress and can now see the slow and blurred props on the model. I can see the slow on all close LOD's and the blurred at one LOD so at least that's progress. :)
I am going to start the process from scratch and see how I go. Thank you so much for all your help.

You should also know that you don't need nearly as many LODs in FSX/P3D as you traditionally did in FS9.

When you first pull the FS9 model into MCX you can go into the LOD tool and delete most of the LODS. Keep the highest and the lowest and optionally keep 1 LOD that is midway between the 2 (especially if the model is complicated).

You need to do this when you first import the FS9 model before you export it in FSX or P3D format.

Then you need only merge 2 or 3 instances of the props.