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

Bug Reports Aircraft & Systems
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Another good question. My guess would be:
It is hard to talk from a level of competence and confidence here as a user and customer, since it is difficult and takes time to set up a home cockpit with all necessary hardware controllers and sensitivity curves, from which one then could draw conclusions about the actual quality of the sim realism, more than the deficiencies of one’s own hardware interface…
I often also wonder, what the actual developers use and how close to realism it could get them even only theoretically… I’m confident, would Asobo’s in house sim hardware be sophisticated, we would have seen pictures of it. But we haven’t…

I know a few professional pilots, who all disregard MSFS completely as a flightsim, BUT give it some credit as a PROCEDURE trainer when using study level airplanes like PMDG737 or Fenix320 etc.
They casually slam the plane on the ground when landing, or do the silliest take off rolls, well knowing it doesn’t matter, since there is zero training effect for the real world when it comes to actual hand flying of aircraft.

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You tactfully omitted pilot competence from the list of variables! But yes, I think you require a fairly high degree of knowledge, experience and a well tuned set up to start to appreciate that it’s not you, or your controls, that are the issue.

I’m not an airline pilot and I don’t find button pushing that rewarding…but I do get a great deal of satisfaction flying well modelled GA aircraft - the VFR experience is outstanding. But yes, until ground physics, control surface behaviour (including trim), adverse yaw, icing and proper control surface behaviour are modelled better it’s always going to have some big caveats on it.

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yes, my bad, of course actual hand flying pilot competence needed as well.
But I think we have nailed down the reasons here why Asobo is not facing a bigger sh*tstorm for their ignorance toward improving the flight model realism.
What can we do about it?

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It’s a complex set of issues. Let me try to apply my engineering mind:

  1. The start of the resolution has to be user evidence - good quality empirical data of the various issues with the variables factored. Eg proper flight testing.

  2. Better presentation of the evidence. These forums can be very limiting when it comes to arguing a complex issue like the flight model as we get channeled into single issue stove pipes. There can also be a fair amount of ‘noise’ that dilutes the evidence. So a headline thread with subtopics would be my way of project managing such a set of tests

  3. More engaging presentation of the evidence. I’ll cite the VGSI issue here. This was long identified as an issue - PAPIs at the 1000ft marker make you land long. But I bet hardly anyone knew about it until 737NG Driver made a video about it. That kind of reach is worth a 1000 posts like this.

  4. Get organised! We are customers and we are deeply invested in the product. Other consumers form associations to give weight to their voice. MSFS pilots union, anyone ? (I’m only half joking here).

I’m not going to bash Asobo - they have tough job and are responding to all sorts of market and customer signals and have a big client to keep happy. I appreciate their engagement and clearly they can be sensitive to consumer feedback. It’s just that their method of gauging feedback places a lot of weight (or so it can seem) on the volume and not the quality. At the end of the day if we want change, we have to argue our case.

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There’s a good video just posted in the Bf-108 thread illustrating some of the discussion of crosswind behavior during takeoff.

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There are a lot of folks who don’t know what they don’t know and user needs run the gamut from: “how do I turn the plane on” to “how do I properly execute an NDB approach.” All valid.

But aviation is one of the most interdisciplinary fields in the world. There are so many things going on at once that it takes pretty extensive education and experience to put them all together. And despite that, even the most experienced pilots are still learning, every flight. It’s an unspoken requisite for the job.

Yet, one of the biggest factors missing from the sim is risk. We can do it right or wrong all day and it doesn’t matter. You get up after the flight, no matter the outcome, hug your loved ones and continue about your day. So doing it “wrong” (in a way that would impart real-world risk) begets doing it wrong. In that regard, we meet the sim at whatever level it needs to be met, flaws and all, because whatever works, works.

Just a reminder that you can vote for this :wink:

I’m a firm believer that foundational, fundamental education is the key. This is my prime motivation for being here and doing my stream, etc. There’s no reason we can’t enhance our knowledge and enjoyment of all the joys and challenges of simulated aviation through “simucation.”

I’ll add that it’s not easy to effectively translate or compare real-world to sim, or troubleshoot, isolate, and communicate found issues. It’s an entire skillset unto itself.

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Voted! (I thought I had before). But at 46, well its got some way to go I fear!

I share your philosophy. I’m making my Kodiak tutorials simply to help others not give up in frustration. Likewise, I stream both to educate, but also it does introduce risk (the risk of embarassment, haha). It also forces us to focus on good practice and to review and learn. Same for using OnAir or Vatsim. (I certainly dont expect to make my YouTube millions and buy a real Kodiak…)Those environments both introduce consequences for failure. So there are risks, just different kinds.

There are limits to what can realistically be expected in a home simulator (as in the discussion on turbulence or ATC - what some players would like is beyond any reasonable expectation) . But it’s the things that can be reasonably addressed so there is at least an approximation. You yourself have done a great job of identifying several of just these issues. The question remains - how do we get it out of the dusty corners of these threads and onto the agenda?

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Link? Would be good to see. Not that I’m ever likely to fly the Bf-108, but who the audience is and how they discuss the issue would be of interest.

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Oh, I embarrass myself all the time. It’s actually one of the fun things about streaming - it adds a lot more task saturation, real-time interaction, and humility. I’m learning all the time as well, but some of that is through discovering the limitations of the sim, the seams at which it goes from being fairly realistic to not at all, and more than anything, taking risks I’d never take in real-life, pushing the boundaries of comfort. Like single-pilot partial-panel NDB approaches in icing conditions at night. Real-life, hard nope; sim, why not?

There’s a lot of “this is why we don’t do this/ do it this way” we can learn from the sim.

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I’ve streamed some horror story landings… But yes, we get to do many things we would never dream of doing IRL…but one thing I am most desirous of is to GO IN A STRAIGHT LINE WHEN LANDING IN A 4KNT CROSS WIND!

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Interesting. And the same issue highlighted above at several times in this thread is flagged again - a sudden, dramatic, increase in weathervaning at some critical speed. Same thing in the CJ4 at c80KIAS.

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Its a long story, according to Asobo its… fixed :rofl:.
I opened topic like this long time ago, see this:

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:unamused: I’ve noticed it’s better the last few flights, but I’m on SU11. It may be the aircraft I’m flying are modeling wheel friction better.

The best way to test it is use a 7 knot right crosswind (in a single engine prop plane). If you’re having to sustain left rudder to maintain centerline during the takeoff roll, it’s not fixed.

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The problem with MSFS is that the wind turns on on the hull after reaching a certain speed (according me about 35-40 kts or 65-75 km/h), and goes out the same way. This means that suddenly there will be a wind that will push you off the main, center track. There is no such thing that the wind strength increases gradually with increasing speed as it is in real life and in many simulators, even “old” like FSX/P3D or DCS for example. This is an obvious bug, as it basically makes rudder ineffective, which is especially bad for taildraggers :face_with_symbols_over_mouth:. I still don’t understand why the problem is not solved. Developers of models get blame according users, but it’s the MSFS engine that has the problem to a greater extent.

This is typical take off in MSFS with kind of small wind:

It’s true that at this (about 35-40 kts) speed the wind creates lift mostly for GA, but it acts on the hull from zero speed and probably someone here hasn’t done their physics homework :frowning:

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There are so many things happening with this and missing some data with which we might isolate a specific cause. I’ll try to unpack:

  1. As you likely know, a propeller that is rotating clockwise (as viewed from the cockpit) is going to impart left-turning tendencies - p-factor, torque, spiraling slipstream and for tailwheel aircraft, gyroscopic precession (at the moment you bring the tail up). Without getting into the specifics of each of these, let’s just say yawing and rolling left at high power settings and low speeds is normal and right rudder is usually needed to correct.

  2. The rudder, if unassisted by a nosewheel or tailwheel steering, has less control authority at slow speeds due to lack of airflow, however, the propwash at higher power usually helps.

It looks like you have full right rudder the entire time. I’m not familiar with that aircraft’s flight model, so I don’t know how effective the rudder is. Is there a rudder trim setting at all for that aircraft? Part of me wonders if this specific case is simply attributable to the aircraft design?

  1. A crosswind will usually impart some yaw due to weathervaning effect (this is the main point of the thread, no?). This is much more pronounced in a tailwheel aircraft, in which the main wheels are usually set more forward, closer to or ahead the center of gravity, leaving a larger surface area behind than in a tricycle aircraft.

  2. Aileron should to be used to counteract the upwind wing’s tendency to lift first (which imparts a lot of unpredictable forces on the wheels, which leads to pivoting/rolling, more lifting, and eventually a ground loop or other loss of directional control). As the speed increases on takeoff roll and the controls become more effective, reduce the aileron.

It looks like the yawing moment is happening when the tail raises. That’s when I’d expect it to do so because of gyroscopic precession. The tail is usually going to raise at a specific airspeed, depending on the plane. You have an 11 knot left crosswind component, so that’s contributing to the left weathervaning and overall left turning tendency. That’s more crosswind than I’d attempt in many tailwheel aircraft.

Where I see the sim falling short is more with tricycle aircraft, where friction on the three wheel points (with mains being farther behind the CG) should overcome weathervaning in all but the strongest crosswinds (we’re talking like 20 knots or greater). In those cases, I’ve had a light right crosswind overcome the left turning tendencies and cause me to use sustained left rudder, which never happens in real life. But it could be contributing to things here as well.

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I took off the other day with a 1.5 knot right crosswind component in the C172 and I was having to apply left rudder. That’s when I went and created a script in Spad.next to add some left rudder trim as a function of throttle and angle of attack. It’s better now, but still not great.

As @PlatosCave4408 said, these problems with the sim become more evident when you have better hardware, but I really wish Asobo would dedicate some effort to fixing the yaw behavior on the ground and in the air on their GA aircraft. I’ve long since voted in all threads on this subject, though, so all I can do now is wait and hope.

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Hi, thx for post :+1:, of course, you are right if we are talking about reality, it would be possible. But unfortunately you got carried away with fantasy and personify MSFS too much in relation to realism :wink:. MSFS does not work that well, at least not yet, and the topic of crosswind is primarily related to problems in modeling quite simple functions. Torque effect like this it could be possible but not with this Argus engine, maybe if we use Twin wasp here (btw. I don’t think I’ve even encountered the torque effect anywhere in any model in MSFS yet), also note that the RPM has been increased gradually. Its also worth adding that I did take off from the other side (unfortunately I don’t have a video) and it was pushing the same to the houses, so it’s no Torque effect Im 100% sure). The rudder in MSFS hasnt alomst any effect at low speed (only the tailweel works), so you can’t counter the pressure of wind gradually like in real live, here it starts working suddenly as you can clearly see in the video, I deliberately use the rudder to the maximum from the beginning to show this senseless behavior, ailerons do not help here either and their effect is negligible, I know this technique and it could be used, for example, in P3D, nothing helps here, in MSFS at all.

And now the most interesting thing, I did this test then exactly in the same conditions but with full rudder to the left and also free (neutral with correct correction like IRL), the effect is identical. This just shows exactly where MSFS has prioritized and how unrealistic it presents behavior in this respect.

So yes, you are right in what you write, but if these were the effects here, I would be happy, because any person with aviation experience would be able to deal with them intuitively. Here at MSFS, we have a set of incomprehensible cases that, regardless of the pilot’s behavior, cause the same thing, without affecting the aerodynamic behavior of the aircraft. Undoubtedly, this is one of the greatest sins of the authors of this simulator. I think that, for example, the side wind is great in P3D (along with Active Sky), also in DCS it is impeccable, you can even fly with the scissor technique, which is practically unattainable in MSFS. They should fix it here and it should be priority for Asobo team. :pray:

I read once interesting hypothesis that it could be the tire edge effect (what? :innocent:), which causes this behavior in MSFS if there is a crosswind (so it would be something completely different, maybe the weather is ok after all, but the probem is elsewhere). Who knows maybe it’s true. :pensive:

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@rafikst can you have a look in the “flight_model.cfg” of the aircraft (it’s the BF108), what these values are set to?
ground_crosswind_effect_max_speed
ground_crosswind_effect_zero_speed

These define, when the crosswind effects sets on depending of IAS (the unit is pecularily ft/s)
See SDK documentation: flight_model.cfg

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I dont see those values in model’s cfg.