Ground effect too strong in windy conditions

Bug Reporting Hub Aircraft & Systems
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Had the same experience "all the time " with a C172, the Aermachi 339 jet, maybe others too I don’t remember well now. You can’t handle these planes at stronger crosswinds during the beginning of the ground roll or at the end of the landing roll.
IR you would not have any difficulty at all when doing it right.

bye, walter

OT:
While some planes behave phantastically with the new wind/gust modeling,
the Aermachi 339 for example is unflyable. The plane is widley waggling too and fro, from left to right at strong winds. The C172, as I’m aware of after some time, behaves not much better, probably others too.
Fascinating as this sim is, a lot remains to be done.

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I experience the same problem since SU9 or 10. I tested different wind strengths and it seems that 10kn crosswind is the threshold for C172. I could takeoff with 9kn crosswind, but not with 10. With 10 I ended out of runway with full rudder or whatever I tried to do. I even tried to push forward to put more pressure on front gear and increase friction, but no difference.
And the same behavior is with C172 G1000 and classic. It is interesting that they don’t have exactly same flight model. G1000 uses CFD, but classic one does not.

I got Study-Level addon for C172 classic from WB-Sim and it has updated flight model (next to other realism features). It copies CFD from G1000 to the classic one. But more importantly I could easily takeoff and land with 13-14kn crosswind. Well, easily, after 1 hour practice and 1 quite hard landing triggering ELT.

Really nice add-on. I am not going back to Asobo version.

I understand there was some discussion between WB-Sim and MS about licensing of Deluxe aircraft. Maybe now Asobo could take over some fixes from WB-Sim.

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Cross link to this discussion: [All aircraft] Crosswind takeoff/landing physics very flawed since release - Bug Reports & Wishlist / Aircraft & Systems - Microsoft Flight Simulator Forums

This has been my main issue (rather than the speed issue of the original report), however which I think this bug report also covers. Mainly the fact that it’s impossible to hold the centreline or even stay on the runway for that matter in strong crosswind conditions (even turning ailerons into the wind etc etc). In essence the ‘weathervaning’ effect is too strong. There has been moves to add configuration to make the wheels more ‘sticky’, however this doesn’t cover all planes and seems like a bit of a workaround. Happy for the workaround for now, but those settings don’t work on most planes

So many lovely new planes, sceneries and features coming out these days, however, if you can’t even take off half the time, then it’s all not much use.

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26

So, I just tried a super simple experiment that proved beyond a shadow of a doubt that the hypothesis of this thread is spot on.

The maximum demonstrated crosswind component of a Cessna 172 is 17 kts. That is not a legal limitation, insofar as it’s not a violation of any FAR to attempt to takeoff or land in winds that have a higher crosswind component than that, but I’m not sure how relevant that is to the sim.

So, I set myself up on the end of a runway with precisely a 17 kt. crosswind. Using FULL RUDDER DEFLECTION, the wind blew me off the runway within about 100 feet, and I’m not talking about my left wheels going off, I was so far off that I would have died if this had been real life. At least 100 yards from the edge of the runway until I was able to get airborne, which only happened because you can take off a 172 at about 50 kts, or less.

What is happening is that the computational fluid dynamics (CFD) being calculated as effecting the vertical stabilizer is either way more than it should be, the coefficient of friction of the tires against the pavement is way less than it should be, or possibly a combination of both.

I repeated the test 3 times with identical results each time, independent of whether or not I steered the ailerons into the wind as you are taught to do during RL flight training.

I also attempting to taxi in the same crosswind, which was at least possible if I was at essentially a speed no faster than a normal walk, but quite difficult even at that.

I’ve made many crosswind landings during my piloting career (which is in all likelihood sadly over), and most of the time it becomes muscle memory to the point you don’t even have to think about it. I do doubt that I ever took off or landed with that much of a pure crosswind component, but that is the primary reason airports have multiple runways in different directions, so as to minimize the odds of even needing to attempt that.

However, for a sim self-described as ‘as real as it gets’, it’s done a ■■■■-poor job on this aspect. Don’t get me wrong, I have and always will be a fan, as I spend more time with this sim than most people do with their jobs, but this is something that has been an issue from day One and has never to my knowledge been addressed.

This is with the SU12 beta, but it’s not new.

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27

Incidentally, since most real word conditions do not include taking off with a max-demonstrated crosswind factor, my experience has been that at the beginning of the takeoff roll, when there is little to no help from the rudder and vertical stabilizer from an aerodynamic perspective, you have to over-correct opposite the crosswind which usually results in movement towards the side of the runway in sane winds. But when those aerodynamic forces turn on, which seems to happen instantly, rather than gradually as they would IRL, all of a sudden what was not enough control to overcome the wind becomes too much, and you end up whipping from one side of the runway to the other because the control input was too much aerodynamically.

I hope that made sense to someone other than me!

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@KevyKevTPA

not sure if this of any help (beileve me, I also feel the crosswind effect is wayy too much).

Devmode (via general options) does have a logging tool under debug > aircraft > Aircraft Data

data.PNG
data.PNG1095×669 79.3 KB

Just plotting the rudder deflection

Left_right_rudder
Left_right_rudder928×564 61.4 KB

What I’m thinking; If an enviroment occurs with crazy crosswind behaviors, it might be ideal to log this graph. In theory, if the cross wind remains steady, than the same amount of rudder and alierion must be held to hold a heading (should denote as a steady line on the graph). What I’ve been noticing is regaurdless of controls (i.e. conerning headwind, tuck the alerions into, etc), the wind just whi[s the 172 around (IRL the wind can take the skyhawk, but at least there’s still control)

Edit: I’ve made many crosswind landings during my piloting career

I feel yah man, the last couple times up in the patten, the winds were 300 @ 14 gusting 23 (with a 34 facing runway). The first attempt landing I was sideslipping all the down (the CFI could def feel the tension). Thankfully the CFI mentioned “just crab down and and the last second, rudder” (it helped out).
If it was any consolation, even the jet’s were having some diffculty (the wings were rolling a reasonable amount when coming across the threashold).

Don’t kick yourself

29

Just one more testimony from a real life private pilot. Ground handling even with moderate crosswind (7-10kt) is almost impossible under MSFS with the default C172 or DA40 (for example).

Maximum rudder action combined with appropriate “stick into the wind” does not allow you to stay on the runway. Obviously this is not realistic at all, and it even prevents a clean takeoff in perfectly standard conditions.

MSFS is a beautiful piece of software overall, and I just finished to port my entire home cockpit and software to it, but it’s very disappointing that it can have major flaws like this one… that make the whole thing almost unusable in real world wind conditions. Especially surprising when there are some quick-wins to solve it even if they are not perfect (friction settings).

The funny thing is that in my region we almost have constant windy conditions, but in the end it’s easier to find “flyable” conditions in real life than in flight simulator 2020 :rofl:

PS : please vote for this one !

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