[All aircraft] Crosswind takeoff/landing physics very flawed since release

The wind comes from your right, so when you touch ground, Should be your left wheel the first to touch ground?

I think it should be the right wheel the first to touch ground.

Sorry for my english.

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You are quite correct well spotted :slight_smile:

UPDATE: I have re-watched the video and I think I may have applied too much left rudder to straighten up before touching down.

Flying in MSFS is a lot more difficult than in real life…

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Hi. I am non IRL pilot and have absolutely no understanding of weather physics but it seems completely broken in SU10 to me.

I’ll explain my problem and hopefully you’ll have the answer for me and explain how its accurate to reality.

This is my flight setup. Cessna 172 steam gauge, live weather departing from Wick airport in Scotland starting cold and dark.

I’m sitting in the plane with everything off. I can hear the wind, but it’s not influencing my plane yet. Rock solid not moving. I turn on the battery, alternator and avionics. Fuel pump in, set my beacon and nav lights on so far so good.

Start the magnetos apply some mixture, lift hand brake.

Now the wind magically appears. I haven’t even applied enough throttle to start moving yet, practically on idle but my plane starts blowing to the left. I apply differential braking and it manages to hold the plane in a straight line, standing still.

I communicate to ATC that I would like to depart straight out and taxi north.

They instruct to use taxiway A out to runway 13.

I cannot get to runway 13 because even with full right rudder, differential braking the plane wont’ turn right because its being blown to the left.

In the end I just let the plane blow to the left, and decide to make for the grass as I can’t reach the runway.

I apply max throttle the plane wants to careen off to the left but with my right foot fully on my rudder pedal I’m able to keep the left lurch to a mild camber.

Building up speed to 55 knots I pitch up, coincidently at exactly the same time the wind stops and I’m now up in the air, having taken off from the grass and now enjoying a nice smooth and stable flight.

The weather phenomenon that only affects the plane on the ground and when the engine has been turned on has abrubtly vanished.

If you know of an IRL pilot, experienced simmer or meteorologist that can provide an explantation for my ignorant ears I’d love to hear it.

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Yes, the crosswind componment does exceed the recommended value within 172 POH. The problem lies with how the model behaves on the ground.

The issue come into how, even if you’re facing into the wind, the turn tendency on the ground got very whacky
Case example; Winds 330 @ 24 gusting 30. Trying to taxi to the SE/NW runway (16/34) the controls did not maintain consistency, even if observing the standard dive into the wind (if headwind) / dive away (if tailwind) method. If I attempt to turn to the left, the plane will then start turning to the right (with the exception being the plane would weathervane to the left, without rudder correction). Even if applying full left rudder, it would still turn to the right at the same velocity (a skid condition perhaps) . It would require full braking to stop the spin. I was doing donuts.

After correcting, repositioning the plane to face into the wind, it then spins the opp direction with the same inputs. The plane then “tipped” (as mentioned in the piror post), and when you’re using an occulus rift, it def throws you off, seeing yourself at a 30-45 degree pitch, while at a 30 degree yaw.

I’m wondering how the model came the conculsion of being inconsistent on the turn behavior with high ground wind speeds

(Edit; can the fourms please add a spellcheck feature please)

To the alleged “real world pilots” claiming everything is correct on MSFS:

If you try to land on MSFS with a C172 and 33kt crosswind, you’ll end up in the grass next to the runway (if you are lucky to get to the runway)

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There is definitely something wrong with the ground handling of the aircraft in MSFS. Try taking off in a 152 or 172 with 15 kts direct crosswind and enjoy the inevitable runway excursion even with full rudder deflection. It’s great!

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How the wind effects an aircraft on the ground is different from when it is in the air because the wheels act as pivot points, resisting the effects of the wind.

Basically as a cross wind applies force to the aircraft it will pivot around the wheels. As there is a larger surface area to the aft because of the stabiliser it means the nose will always turn into the wind as the force of the wind is stronger - you turn like a weathervane into the wind.

With the parking brake applied the SIM holds the aircraft in place. In strong enough winds once you release the brake the aircraft can start to get pushed around. As you gain speed on a takeoff roll a complex process starts where the various forces acting on the aircraft alter dynamically (flight control surface authority grows, wheel friction reduces as the wings start to create lift, but intertial forces also increase). It’s especially complex in a high-wing taildragger.

But as soon as you are airborne there is nothing anchoring you to the ground acting as a pivot point - you are now afloat in the stream of air and moving with it and the vaning effect stops. The reverse is true when landing.

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The 172 is at best half tuned for crosswinds currently, in it’s default state anything stronger than a stiff breeze and you’re going to have problems.

This has become incredibly hard in light aircraft since SU10 dropped, I can’t remember it being this bad during the beta. The slightest crosswind and it’s full rudder, that ain’t right.

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Thanks, this is a really helpful explanation. I’m not so clued up on technical term so can I just clarify a few things?

So the reason the plane wasn’t moved around in my example above prior to starting the engine, was probably becase the wind forces occured when I lifted the handbrake, and that is therefore accurate? That does make sense.

When you say there is a larger surface area to the aft, do you mean the back of the plane with the tail? is that what the stabliser is, the tail with the shark fin? Apologies for my lack of technical knowledge, MSFS is the only flight sim I’ve ever played and I’ve never even sat in a real GA plane.

When you say the nose will get turned into wind. I think I understand. So if the wind is blowing from the left to the right as I’m travelling down the runway, the wind will turn my plane from the tail end, so I will now be turning into the wind with it blowing directly over the front of the plane?

If so that is totally counter intuitive to what I thought was happening, which is the wind was blowing across the runway from left to right that I’d be blown to the right.

If you can confirm I’ve got the above right it does at least give me something to build on, as my intuition of how the wind was blowing me and in what direction seems to be have completely wrong.

If the wind was blowing left to right across the runway, what way do I turn the yoke for aileron correction do I steer right to resist turning left or steer left into the wind?

You got it all right.

The weathervane effect can seem counter-intuitive. You counter it by using the rudder and with rudder trim also (depending on the aircraft type). But as you apply rudder that has the effect of rolling the wings too, so you need to counter that with aileron. The wind itself will create a rolling effect as it will create differential lift on each wing - this is especially pronounced on a high-wing aircraft like the 172.

Now here is the thing - as soon as you lift off these forces will change. Now you will drift in the direction of the wind and if you want to maintain the extended center-line you will have to quickly but smoothly reverse control inputs.

Flying a light GA aircraft in strong winds is challenging and many of them have real limits on how much cross wind they can operate in . So don’t expect smooth take off and landings if you have a 30knt cross wind!

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Agree 100%, this is well said. That’s a good idea with your license in your avatar, I should do the same.
The gust frequency is an issue, ground friction is an issue, twitchy ground control is an issue, but the biggest killer of immersion is the EXTREME exaggerated Weathervane effect. Fixing this needs to be their 1st priority in order to be called a simulator.

I marvel at the job they’ve done with the global rendering and weather, it is truly a huge evolution. But let’s get the very basic fundamentals of flight down now.

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I’ve read every post in the thread, and I agree that the ground handling part of the sim needs some serious work (among others). Dropping a line to say thanks for persisting with this for months, and to the others for keeping the thread active!

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since the su10 i’ve observed that many small propeller planes like the c172 or arrow feel like they are made of paper in crosswinds, sometimes below 10 knots. Sorry for the expression but I can’t think of any other description. Even in the SU10 beta, the aircraft were significantly easier to fly under the same conditions. I’m not flying with an Xbox controller on the Xbox SX. I put together a small cockpit and I can definitely say that there is something terribly wrong with the ground physics

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The only thing that changed after SU10 is the new silly turbulence/gust system that is very annoying especially in live weather. This added to the wrong ground physics made crosswind landing way more difficult than in real life.

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Had a similar experience yesterday (C172 G1000). Did some patterns in live weather and according to the windsock, I had a mild crosswind component of some knots (I also checked this with simvar-watcher). But on the ground during takeoff and landing, it felt like a ten times bigger crosswind. While ground physics always had its peculiarities, I did not encounter such a strange behavior in light winds before…

Edit: I read this in another thread about ground handling (https://forums.flightsimulator.com/t/is-there-something-going-on-with-wind-or-runway-friction). Will try this out…

Solution: I enabled legacy flight model and restarted the sim. Then I changed back to modern and restarted the sim. Voila!

Edit2: Tried this out, did not change the behavior.

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yup this whole gusts has been very annoying, wish it could be disabled in live weather.

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Just checked the new development update. The ground handling problems introduced specifically in SU10 didn’t make the report list for new bugs reported in the last three months which is why I was annoyed that the thread Merkuel posted up a couple weeks ago got merged with one from over a year ago.

Hopefully they are reading the forums at least as there’s no Q & A until November so live weather probably a no go in the 172 for the rest of the year.

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For Xbox users yes, for PC users you can just go to the flight_model.cfg and delete the lines

ground_crosswind_effect_max_speed = -1000
ground_crosswind_effect_zero_speed = -1000

and it will return to it’s exact pre SU-10 state.

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Really, as easy as that? I though they added some complex new weather physics, not two lines of code? I will try it tomorrow and be mightily pleased if that works!