Why is the ground handling upon touchdown off?

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So lets talk physics for a second, if you are coming down on a runway, no matter the wind, once your landing gear which points directly forward touches the ground, it should be easier to stay in a straight line. Compared to a second before when you were battling the wind and you were not touching the ground. But in MSFS the opposite seems to happen. Upon touching down, most planes want to go off a straight line, often violently.

Is this something hard to fix? Or am I off base and is this a unique problem regarding my setup?

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I agree.
Seems ground friction is barely modelled.
The wind has an outsized effect on aircraft during taxi too. The amount of power required to taxi with a headwind vs. tailwind is highly unrealistic.

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@Summer1Man Are you applying any rudder, and aileron connection on touchdown?

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Yes sure, the problem is; with crosswind you lineup with the runway and come down straight enough, but upon touching the ground the planes want to go left or right off the line, in a rather physics defying way.

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The obvious answer may be you either aren’t adding enough rudder correction to stop this, or you have run out of rudder authority, and the crosswind is beyond what your aircraft can handle.

The less obvious answer is the sim still has issues with ground handling, but Asobo added some options to deal with this, but these need to be tweaked on a plane by plane basis. Two variables control at what point the effects of crosswind begin to be felt, and when they stop. The other two variables control static friction for the nose, and main gear.

You didn’t say what plane you are flying. Could you elaborate, or perhaps post a link to a video demonstrating it?

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This isn’t something that players should have to deal with, though, this should be something that plane authors at Asobo and other developers set up correctly before they distribute their planes.

Ground handling is known to be bad, and there are many many many threads about it.

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I think it may well be a combination of the things you mention. But I do think the biggest thing is the issues with ground handling. I will try to update a video if I can, but it is pretty hard to miss what I mean, if you try to land in any crosswind with the Hawk T1 for example. A similar thing happens pretty violently on t/o as well with that plane.

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Preaching to the converted here, but it is what it is.

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This seems to be the issue, I also found some of the threads after some looking. Some planes are better than others in this regard I think.

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I’ve never flown the Hawk so I can’t comment on that plane specifically, but you haven’t given enough detail to comment further other than mere speculation.

Plane, crosswind velocity etc, plus a video would be useful, but my guess at this moment is you aren’t putting in another rudder but I may be wrong and it’s a defect with the Hawk.

I’ve been looking over a manual for the Hawk, and there is a passage that states the crosswind component should be no more than 15kts for runways up to 150ft wide, and 20kts for runways wider than 150kts. That’s not to say what the simulated Hawk can, or cannot do, only what the real world one should be capable of. There is another section that states the flaps should be in the DOWN position rather than MID or UP.

https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/948765/Binder1.pdf

How do you get on with other planes, by the way?

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This is a physics problem that seems to puzzle simulator creators from all works. And it’s an issue that has been around for a very long time as well.
In some versions of MS FS it was less pronounced and sometimes it could be corrected to some degree in the individual aircraft cfg files…by tweaking friction numbers and power efficiency numbers to reach a happy medium.
I know we did that with the Connie’s for FS9 and FSX.
But the same is true to some extent in Xplane as well.
I always likened the effect to landing on a frozen runway and the trajectory vector at the moment of touchdown is locked in until you are stopped.

With real airplanes in strong crosswinds one technique is to use the upwind main wheel to plant the aircraft and then lower the other main and finally the nose wheel.
Executed absolutely perfectly of course that upwind wheel rolls along parallel to the centerline. Realistically it is lightly at an angle towards the wind and is rotated as the other main is lowered.
In MSFS that is enough to have you go off into that upwind direction afterwards until stopped.
Some of that tendency to turn could be the wind forcing the airplane to weathervane.
If you increase friction forces you can reduce this issue, but you also end up needing much more power to get going.

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What you see is what has to happen. As you say it´s plain physics. But short answer for MSFS is that both weather and aircraft simulation are currently broken like hell and it has been like that for really several months.

For instance during this week I have been flying over Vietnam for quite a long time. Real weather reports included 3-5 kts, always in the prevailing wind direction for this country which is from sea (NE) to inland (SW). Game live weather included 30-40 kts quickly oscilating winds in all directions, even below 1000 ft, during the whole week. And it´s not even Monzon time yet… There are few weather stations in the country, and interpolation of data clearly fails as soon as the amount of sources is not enough resulting in those crazy winds.

On the other hand, as explained above, flight model configs can tune both the crosswind effect and the wheels friction in the aircraft addons. If not done correctly you can see rolling rockets going out of center line even below 100 kts. Not to mention that some tailwheelers can even go 90Âş out of runway during the transtion to 2 wheels, no matter what you do.

Cheers

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In RW transitioning from flying to rolling in a crosswind is a demanding task. Extremely demanding if you fly taildragger, for which you must train especially to avoid a condition known as a ground loop.
I one of the development videos Sebastien from Asobo explained that they still have a lot of work ahead to properly simulate physics of this transition. It’s never a binary transition: either flying or rolling. If there is a speed there is also a lift so part of the plane weight is supported by lift and part of the wheels - this is not easy to be mathematically modelled.

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A friend of mine just posted this elsewhere, thought it fits here as well.

By: Raven Mazankowski

Tailwheel planes have to land slow because the nose points up, and nose up plus speed makes planes fly. But don’t go too slow or you’ll crash! And bring the wind-side wing down so you don’t flip over, but not too far. And also straighten your butt with rudder so you land straight. Landing diagonally may make the plane flip over or spin around in a tiny, destructive circle, the prop hit the ground and breaking -everything-. Land on the windy-side wheel first, but don’t accidentally turn. Then put the other wheel down. Then push forward on the yoke to keep the tail up so you don’t try to fly again. Then, before the plane falls over forward, bring the yoke back to put the tail down. Do this with authority: stick it. Here’s where you find out if you did it too soon and had too much speed: you accidentally lift off about 20 feet and then crash to the ground. I’ve seen it happen.

While all of this is happening, also move your feet around on the rudders you keep the plane pointing forward, because it reaaaallllly wants to spin around backwards. Every time you touch the rudder on one side, you have to do it a split-second later on the other side to stop the plane’s reaction. Repeat. Don’t rudder too hard or at the wrong time; the plane will ground loop, prop-strike, break everything. I’ve seen it happen.

Also, you can’t see the runway because the tail is lower than the front, so just trust it’s still there and a coyote hasn’t run in front of you, or whatever. Slow down on the runway slooooooowly, adding brakes carefully so you don’t flip over forwards. I’ve seen that happen.

While you are doing all this, listen to air traffic and answer if they call your tail number. They may be saying something important about that errant coyote.

Congratulations, you’re on the ground! You still have to keep using the rudder and ailerons to correct for wind as you taxi and talk to tower, then ground, and use all inputs to taxi home, being careful not to spin the plane around into anything. The butt is low and way back there, and runway lights are tall.

Drag the plane backwards into the hanger. Have a healing adrenaline-cry and take a nap.

In contrast, landing a nose-wheel plane:

Bring airspeed to 70kts. Aim for the ground. Three feet above the ground, try not to land. The plane will land. High five yourself as you taxi home with one hand, waving at tower.

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Thanks for the forward, I should add one thing for anyone coming across this thread in the future; it seems to be mostly about strong crosswinds. It catches you unaware in MSFS because you don’t expect strong crosswinds given the weather that day but it may well also be accurate for that location that day.

To sum up, when I kept trying it seems less about the sim acting in an unrealistic way, and more about me refusing to recognize strong crosswinds.

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I think that is something that comes with practise, in the absence of a visible wind sock being aware of how far your nose is pointing away from your course to know which side the wind is coming from, then correcting for this.

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Interesting topic, I think ground handling is a little overdone as well.

Im no real life pilot but you don’t normally watch pilots fighting the controls on ground.
Even during taxi it can be a fight most times to keep the aircraft in a straight line, especially in light aircraft. I realise you need to negotiate for any crosswind and such, but I just think its a little overdone in the sim.

I hope they look into this.

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They are, but in real life it is easier, so it is not much of a “fight”. You feel the wind and make corrections with controls, I think it is more difficult when you don’t “feel” the wind and the aircraft as it takes your instincts out of it more.

That being said, some adjustments could be made probably. It seems to depend on aircraft in MSFS as well. Some are just better in their flight model.

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One thing that was added a patch or two back was the ability to adjust static friction, and at what airspeeds a crosswind affects the aircraft.

Playing around with those values can help, but you’d need first hand experience to set something that felt realistic.

ground_crosswind_effect_zero_speed
ground_crosswind_effect_max_speed
ground_high_speed_steeringwheel_static_friction_scalar
ground_high_speed_otherwheel_static_friction_scalar

I believe those are the four values, referring to the SDK:

https://docs.flightsimulator.com/html/Content_Configuration/SimObjects/Aircraft_SimO/flight_model_cfg.htm?rhhlterm=static%20friction&rhsearch=static%20friction

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