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Inherent flaw of FSX to give too much ground friction?

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Hi All,

 

Thank you guys for all the information and effort to fix the FSX ground friction issue. I'm pretty excited about this new development.

 

I looked in the DynamicFriction.lua file but had a few questions:

I saw where one user had indicated that FSX applies various friction reduction levels for wet, snow and ice covered surfaces. Has anybody been playing around with those values?

 

Can those values be set via the lua file as well?

 

I havent tested it out but has anybody seen where the friction reduction levels for wet, snow and ice covered surfaces plays a difference in the takeoff and landing performance?

 

I suspect that if aircraft developers are made aware of this development then they can really use this to enhance the realism of their aircraft without having to spend significant time working on the air file itself.

 

I suspect the DynamicFriction.lua can be further enhanced. I like the fact that it handles taxi operations realistically below 30 kts and resets the ground friction to default above 30 kts so that for the most part our takeoff and landing performance remains the same.

 

What would be interesting is if the DynamicFriction.lua can increase the wet, snow and ice covered surface friction levels during takeoff and reduce them during landing which would esentially give us longer takeoff and landing rolls when those conditions are present. The lua would need to factor for a RTO event as well since it would need to factor a slower acceleration to V1 and slower deceleration from V1 to 30kts where the lua switches back to taxi operations mode.

I suspect the best way to implement something like this would be to have the lua look at throttle position above 30kts (outside of taxi operations mode). If the throttle is above a preset value say 50% then the lua can assume the aircraft is trying to takeoff and would therefore increase the wet, snow and ice covered surface friction levels to simulate a longer takeoff roll when conditions are not dry. If the trottle is below the preset value say 50% then the lua can assume the aircraft is trying to land and would therefore reduce the wet, snow and ice covered surface friction levels to simulate a longer landing roll when conditions are not dry.

The advantage of using throttle position versus others would be that RTO situations could easily be handled. I figure that most developers could then set their own values for wet, snow and ice covered surfaces when trottles are above and below the preset value so that the aircraft behaves closer to the real thing.

 

Regards

 

Kamal

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  • Hi everyone; I've been steered over here by folks who are extremely interested in what's being discussed. As an adviser on realism for MSFS going back to the FSX Beta process I can tell you that this

  • 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. -

  • Pete Dowson
    Pete Dowson

    Okay. This is done in version 4.859i of FSUIPC, downloadable now from the Download Links subforum of my Support Forum.   The facilities are enabled by parameters in the INI file. You'll need to look

And also when throttle below 50 percent, the lua could increase the value for sliding friction, to simulate ground handling when touching down in crabbed condition... Great idea working with the throttle!

 

Mas

 

And also when throttle below 50 percent, the lua could increase the value for sliding friction, to simulate ground handling when touching down in crabbed condition... Great idea working with the throttle!

 

Mas

Martin Jensen

You have to account for a rejected take off and bouncing landings, so you would need some kind of timer linked to the in air flag for a landing to activate the higher side friction on landing only and then possibly a go-around if you mess up due to the crabbed landing with higher side friction. Lots to account for.

Cheers, Andy.

Hi All,

 

I think the DynamicFriction.lua already includes increased sliding friction as a default regardless of whether you are below or above 30 kts.

 

Assuming this is the case i think it's easier to just keep it that way. If increased sliding friction helps in tracking the runway centerline during a crosswind situation i suspect it'll also help in a V1-cut or OEI landing situation. In these cases things would get very complicated if you tie the sliding friction to throttle position. During a V1-cut all throttle levers would be forward of 50%, however you would still want the increased sliding friction to help you keep the runway centerline. During an OEI landing situation you may just find that you have the remaining throttle at or above 50%. In some cases it's probably better to fly the aircraft with the higher power setting until touchdown and then retard the throttles to idle. If this technique is used you would perhaps have a few seconds where you would have less than idle ground friction.

 

Regards

 

Kamal

WOW I happened to come across this thread by pure accident. I read it with interest, downloaded the sim1.dll for my FSX Acceleration and fired up my trusty Air Canada 737 NGX. I was simply astonished at the difference. I can now taxi like a Pro lol. I had recently brought the Saitek Pro Rudder Pedals and I can only say that anyone watching me try and taxi anything would think I had been drinking. Good job there's no "Ride Programs" on the taxiways !!

 

I also updated my FSUIPC and it made a reference to adding the following line to the ini file

 

 

PatchSIM1friction=Yes

 

What do I need to add this for? I am just interested to learn what this is for that's all

 

Richard

 

Richard

i7-12700K | Noctua NH-D15S Black Version | MSI Pro Z690 - A | 32 GB DDR4 3600 | Gigabyte Gaming OC 4090 | 1TB WD Blue NMVe (MSFS 2020) | 500 GB WD Black Gen 4 NVMe | 4TB WD Black Conventional | Fractal Design Torrent Case | Seasonic 1000W Gold Plus PSU | Thrustmaster Boeing Yoke | Honeycomb Throttle | Airbus Side Stick | Virpil Rudder Pedals | Sony X90K 55 Inch TV |

mmBbmS1.png

 

Hi Richdem,

 

I hope you backed up your sim1.dll, since you really don't need to use this method anymore. This method works but has the added disadvantage of messing with the takeoff and landing performance of whatever plane it is that you are flying.

 

If you instead use the dynamicfriction.lua method you get all the same benifits you get with the sim1.dll, except that once you are above 30kts (say for takeoff) the lua restores flight sim's default friction values thus preserving the aircraft's takeoff and landing performance.

 

I'm going to do a seach and then talk to a module developer (if i don't find what i'm looking for) to see whether an application could be created that records take off distance (brake release to lift off and brake release to 35ft) and landing distance (50ft to a full stop). If i get this then i figure i'll put the PMDG heavy hitters through the paces and see how they compare with TOPCAT SIM's figures particularly when operating on Wet, Snow and Ice covered runways. If i see where i can improve the realism a bit more then i suspect that i'll try to convince someone here to make a lua based on trottle position that dynamically changes the wet, snow and ice friction values based on trottle position so we can get better takeoff and landing performance realism when operating from contaminated surfaces.

 

Regards

 

Kamal

Thank you very much for the FSX update, Pete. Any chance of an FS9 version?

 

Regards

 

John

Supporter.png

 

John

Hi Richdem,

 

I hope you backed up your sim1.dll, since you really don't need to use this method anymore. This method works but has the added disadvantage of messing with the takeoff and landing performance of whatever plane it is that you are flying.

 

If you instead use the dynamicfriction.lua method you get all the same benifits you get with the sim1.dll, except that once you are above 30kts (say for takeoff) the lua restores flight sim's default friction values thus preserving the aircraft's takeoff and landing performance.

 

I'm going to do a seach and then talk to a module developer (if i don't find what i'm looking for) to see whether an application could be created that records take off distance (brake release to lift off and brake release to 35ft) and landing distance (50ft to a full stop). If i get this then i figure i'll put the PMDG heavy hitters through the paces and see how they compare with TOPCAT SIM's figures particularly when operating on Wet, Snow and Ice covered runways. If i see where i can improve the realism a bit more then i suspect that i'll try to convince someone here to make a lua based on trottle position that dynamically changes the wet, snow and ice friction values based on trottle position so we can get better takeoff and landing performance realism when operating from contaminated surfaces.

 

Regards

 

Kamal

 

Hi Kamal,

 

Thanks for the reply, Yes I have backed up my Sim1.dll. I did read about the dynamic friction.lua method but I am unsure how to implement it in FSUIPC. Would you be kind enough to tell me what I need to do,

 

Regards

 

Richard

 

Richard

i7-12700K | Noctua NH-D15S Black Version | MSI Pro Z690 - A | 32 GB DDR4 3600 | Gigabyte Gaming OC 4090 | 1TB WD Blue NMVe (MSFS 2020) | 500 GB WD Black Gen 4 NVMe | 4TB WD Black Conventional | Fractal Design Torrent Case | Seasonic 1000W Gold Plus PSU | Thrustmaster Boeing Yoke | Honeycomb Throttle | Airbus Side Stick | Virpil Rudder Pedals | Sony X90K 55 Inch TV |

mmBbmS1.png

 

Very interesting topic and great efforts already, thank you very much! :)

 

I wonder if you know AeroflyFS which is so perfect on simulating physics. It is already fun watching the Cessna during taxi from external, seeing how it behaves when rolling on different surfaces. And take-off runs and landings are amazing as it is very important to control your aircraft right, for example not to slip in the moment of touchdown, otherwise the aircraft can get hard to control or you even risk to off the runway or to roll over.

 

Will we be able to see this also with the new possibilites through lua and FSUIPC? Does the dynamicfriction.lua loose effect on slipping touchdowns because it is thought for slower speeds?

  • 4 weeks later...

did read about the dynamic friction.lua method but I am unsure how to implement it in FSUIPC. Would you be kind enough to tell me what I need to do,

 

Regards

 

Richard

 

Could someone pls explain for dummy's how to make this work I have reg version of FSUIPC, what do I need to do to make this work.

Many thanks.

David Murden  MSFS   Fenix A320  PMDG 737 • MG Honda Jet • 414 / TDS 750Xi •  FS-ATC Chatter • FlyingIron Spitfire & ME109G • MG Honda Jet 

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Welcome to Avsim, Marcel. :smile: I think the best combo currently is to use the registered FSUIPC and Bob's modification for the fading friction correction. By this, no detailed addon gets mixed up too much due to the lowered values. However, I would also add the new

since this enables a more detailed ground behaviour including reactions on e.g. the side forces.

 

Click the link to see the video on the difference when it comes to the ground handling. Since Accufeel can be adjusted for any plane, it's a tip.

 

To answer David's question. http://forum.avsim.n...00#entry2541796 Bob explains the auto startup of the additional script.

Thanks CoolP but am still not 100%

You'll need to put the DynamicFriction.lua file into the modules folder, and then in FSUIPC4.INI you need to have an "Auto" section to invoke it, something like this:

 

[Auto]

1=Lua DynamicFriction

 

Where is the DynamicFriction.lua fil?

David Murden  MSFS   Fenix A320  PMDG 737 • MG Honda Jet • 414 / TDS 750Xi •  FS-ATC Chatter • FlyingIron Spitfire & ME109G • MG Honda Jet 

 Fenix A320 Walkthrough PDF   Flightsim.to •

DCS  A10c II  F-16c  F/A-18c • F-14 • (Others in hanger) • Supercarrier  Terrains = • Nevada NTTR  Persian Gulf  Syria • Marianas • 

• [email protected] All Cores HT ON   32GB DDR4  3200MHz RTX 3080  • TM Warthog HOTAS • TM TPR • Corsair Virtuoso XT with Dolby Atmos®  Samsung G7 32" 1440p 240Hz • TrackIR 5 & ProClip

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Where is the DynamicFriction.lua fil?

 

If you install the only currently supported version of FSUIPC4 (version 4.86) you will find that Lua in the Lua plugin examples pack in your FSUIPC Documents folder, which is inside.the FS Modules folder.

 

Regards

Pete

Win10: 22H2 19045.2728
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

Thanks Pete.

Then all I do is add this to your ini

 

[Auto]

1=Lua DynamicFriction

 

yes?

David Murden  MSFS   Fenix A320  PMDG 737 • MG Honda Jet • 414 / TDS 750Xi •  FS-ATC Chatter • FlyingIron Spitfire & ME109G • MG Honda Jet 

 Fenix A320 Walkthrough PDF   Flightsim.to •

DCS  A10c II  F-16c  F/A-18c • F-14 • (Others in hanger) • Supercarrier  Terrains = • Nevada NTTR  Persian Gulf  Syria • Marianas • 

• [email protected] All Cores HT ON   32GB DDR4  3200MHz RTX 3080  • TM Warthog HOTAS • TM TPR • Corsair Virtuoso XT with Dolby Atmos®  Samsung G7 32" 1440p 240Hz • TrackIR 5 & ProClip

  • Commercial Member

Thanks Pete.

Then all I do is add this to your ini

 

[Auto]

1=Lua DynamicFriction

 

yes?

 

Yes

 

Pete

Win10: 22H2 19045.2728
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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