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FSX Sim1.dll in FSX?


I read several posts where people edited the sim1.dll in FS9 to adjust ground friction. It seemed to be a great successful fix.
However almost every thread on this was closed years ago. So my questions:

1. Why aren't there any topics on this nowadays? Does it not work?
2. Can it be used in FSX?
3. Which characters have to be changed in sim1.dll?

Thanks for any help!

@Yves_G once had declared a few years ago in FlighXpress Forun (Germany), how to do that with a hex editor in FS9.
Hallo, Rainer!

thanks for the tip with flightexpress.
As Yves_G describes I went to line 0004A090, but there were no E1 7A 84 3F characters in the line?!
Instead I found this string in 2 other lines, but as I don't know which is what...:(

Maybe the entries were changed in FSX.

Does anybody know which to edit?


P.S.: I would be happy with a working d/l link to an already modified dll. EVERY link I've tried yet was dead!
Last edited:
Hi Steven

The offsets and data structure for surface parameters are different in FS9 and FSX. I created an Excel sheet that lists all the offsets for both simulators.
In FSX there are three new scalars on the two friction coefficents which are applied for rain, snow and ice. This means in FSX the surface condition (e.g. snow) decreases the ground friction and braking force.

Herve Sors' AFSD now shows the ground friction of the current surface.

The Excel-File is available at the following link:

Thank you for the instruction spreadsheet. This helped me greatly to edit both FS2004 and FSX SP2 sim1.dll to obtain more realistic results in crosswind landings and takeoffs. I used a sliding friction coefficient of 1.92 for concrete and asphalt to replace the default values of 0.64.