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chabrier

Inherent flaw of FSX to give too much ground friction?

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The main problem has allways been side friction. MS FLIGHT corrected it... :-/

There are problems with exactly this same subject on other sims, including MSFS's direct competitor - X-Plane10.

 

Each has it's bad aspects, but I still preffer FSX's model, even if not perfect. I know X-Plane's one will probably get addressed during the current v10 cycle... MSFS's will not... Maybe Prepar3d v2.0 brings a ground physics model closer to what we have in MS FLIGHT (still not perfect but very good...) or almost perfect, like in DCS World, Condorsoaring...

 

+1

 

:good:

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With kind regards,

 

Bart S.

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I'd say that the problem is that there is very little ground friction in FSX. It is ridiculously hard to get in trouble landing. Get a little off axis in a taildragger and you should know it immediately, with forces trying to throw you into a ground loop. It should be similar in a tri-gear, with side loads and tire deformation that you should feel in the motion of the aircraft. Others have mentioned the gliding on ice feeling. I think contact with the ground physics are almost non-existent. It's my biggest complaint with FSX. Some addons do get it better than others but none get that close in my experience.

 

So, I have no idea about the coding nuts and bolts but I'd guess that this lack of GROUND physics has been compensated for by unrealistic BRAKING in all planes. That's why people experience "friction" only along the inline axis of the aircraft, and why the OP and all of us sometimes experience silly deceleration rates on the ground at idle. I'd bet quite a bit that even with the brakes off, the code is always applying some braking when on the ground to SIMULATE friction without actually modelling any wheel to ground friction physics. I don't know, but that's my guess from over 1000 hours in many different FSX planes and trying to understand how FSX gets contact with the ground so wrong.

 

I also suspect that very little can be done about it outside of external physics modules on the line of what A2A does. And I'd LOVE for them to tackle this in their aircraft!!

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I think A2A should look into adding something like this to Accu-Feel

 

Obviously they can't fix the problems in fsx completely but I'm sure they could figure something out to make braking and friction more realistic

 

Lee


 

 

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Anyone cared to take a look in the excel sheet instead of rambling on ?

It CAN be done.

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As you mentioned above, looking at a set of hex values we don't understand doesn't tell us much. And I'm not sure what CAN be done without understanding what those values are used to do. I'm not sure there are many people outside the ACES team that know that.

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I have done it!. Now on to testing and tuning, but the first results are very nice!.

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Finding until now:

 

- sliding coefficient raised, saw no ill side effects like in fs9, like the shudder on start of roll.

- steering much more direct, great no more skid on normal taxi speeds.

- keeping runway centerline much better

- rolling friction lowered, little breakaway power needed, then taxi on idle, depending on weight of course

- much more difference on dry versus wet versus snowy runways and taxiways, as it should be.

- needed to adjust the brake value a bit in the aircraft cfg to compensate the lower friction. Easy.

 

Tests were with Cessna, DC3 and L749 and B737 at this moment.

 

AI doesnt seem to bother by the effects.

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no more skid on normal taxi speeds.

 

How fast are you guys taxiing anyway?? I've been able to get a skid in a turn on wet pavement by running way too fast. I like to keep about 12 knots ground speed on the straight and 8 knots in turns. I'll do 15 to get off the runway. I usually fly lighter aircraft, which may make a big difference.

 

Hook


Larry Hookins

 

Oh! I have slipped the surly bonds of Earth
And danced the skies on laughter-silvered wings;

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Finding until now:

 

- sliding coefficient raised, saw no ill side effects like in fs9, like the shudder on start of roll.

- steering much more direct, great no more skid on normal taxi speeds.

- keeping runway centerline much better

- rolling friction lowered, little breakaway power needed, then taxi on idle, depending on weight of course

- much more difference on dry versus wet versus snowy runways and taxiways, as it should be.

- needed to adjust the brake value a bit in the aircraft cfg to compensate the lower friction. Easy.

 

Tests were with Cessna, DC3 and L749 and B737 at this moment.

 

AI doesnt seem to bother by the effects.

 

Just tried it out.... I LOVE it...

 

I can realistically now simulate idle taxi on the NGX. Nosewheel is much more responsive. Thanks so much!!!

 

Also, single engine taxi on the NGX is MUCH more realistic... I can actually chug along at 15 kts without having to constantly leave the single engine at 40% N1.

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Ok, great.. now download the excel sheet, and lets get together about the values, because there are more to adjust.

Like the effects when wet, ice or snow.

 

In your version only concrete,asphalt and tarmac are been adjusted.

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Finding until now:

 

- sliding coefficient raised, saw no ill side effects like in fs9, like the shudder on start of roll.

- steering much more direct, great no more skid on normal taxi speeds.

- keeping runway centerline much better

- rolling friction lowered, little breakaway power needed, then taxi on idle, depending on weight of course

- much more difference on dry versus wet versus snowy runways and taxiways, as it should be.

- needed to adjust the brake value a bit in the aircraft cfg to compensate the lower friction. Easy.

 

Tests were with Cessna, DC3 and L749 and B737 at this moment.

 

AI doesnt seem to bother by the effects.

Just tried it out.... I LOVE it...

 

I can realistically now simulate idle taxi on the NGX. Nosewheel is much more responsive. Thanks so much!!!

 

Also, single engine taxi on the NGX is MUCH more realistic... I can actually chug along at 15 kts without having to constantly leave the single engine at 40% N1.

 

Must have missed it....can you guys post a link to the fix?


AJ Pongress

Boeing777_Banner_BetaTeam.jpg

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Must have missed it....can you guys post a link to the fix?

 

Me too! Please!

 

Pete


Win10: 21H1 19043.1865
CPU: 9900KS at 5.5GHz
Memory: 32Gb at 3800 MHz.
GPU:  RTX 24Gb Titan
2 x 2160p projectors at 25Hz onto 200 FOV curved screen

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Before I have to mail it to everyone, where to put it for download? any suggestions?

I dont know if it can be uploaded to the library, meaning if avsim allows it?

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