In turbulence, wobbling on the yaw axis is overdone and not true to life while on the roll axis is underdone. You can get away with minimal aileron inputs and maintain roughly level flight. There is also this odd accel/decel jerking moment in moderate turbulence which I never experienced IRL.

As sd_flyer says though, trying to simulate these forces and movements when the “eye camera” is stationary can’t be easy. IRL both the aircraft and your body are being bounced around, and never in unison with each other.

Still, I don’t like the way it is currently done, hope Asobo refines their turbulence modelling over time. It definitely can be improved.

In my limited GA experience the constant wobble in the yaw axis is overdone.  CFD is raw and unrefined.

2 hours ago, LRBS said:

I do hope that this constant unsettled movement not to be the new "normal" behavior from now on. Do you remember/noticed what kind of winds you had? 

Westerly winds, no more than 10 knots, no gusts IIRC. 

I think MFS, just as XP12, are too sensible to wind variation.

The rocking in MFS can take place if there are mountains nearby, and with the new CFD supposedly also in cities where hrere are all kinds of obstacles and if you fly low and wind is blowing with some intensity IRL and in MFS you'll be bounced around.

But whenever in a METAR there's a DDDvDDD field expressing variable winds between two wind directions ( true headings ) both MFS and XP12 tend to create variation frequencies which are higher than usual IRL. That, IMO, s one of the most frequent causes for that wind rocking, and I do think it would be great if they could fne tune it.

Austin @ LR has been advised ... I can't reach Sebastien @ ASOBO that easily 🙂

Reported variation is based on 10 min observation, if higher than 60º and according to:

ICAO Annex 3

§ 4.1.5.2:

1) when the total variation is 60° or more and less than 180° and the wind speed is 6 km/h (3 kt) or more, such directional variations shall be reported as the two extreme directions between which the surface wind has varied

2) when the total variation is 60° or more and less than 180° and the wind speed is less than 6 km/h (3 kt), the wind direction shall be reported as variable with no mean wind direction; or

3) when the total variation is 180° or more, the wind direction shall be reported as variable with no mean wind direction"

I thought that in RL yaw movement due to wind/turbulence was uncommon in the air in general. That most airplanes are fairly stable in the yaw axis. On the ground it's different and light aircraft can be susceptible to weatherwaning. Or is this incorrect? 

9 minutes ago, jcomm said:

But whenever in a METAR there's a DDDvDDD field expressing variable winds between two wind directions ( true headings )

While you may be correct, the issue is persistent throughout the flight regions, not just due to variation in surface winds (which can be extremely local phenomenon btw).

Just take a glance at the slip/skid indicator in any G1000 equipped plane in MSFS. It's going literally bananas whenever wind direction or speed is changing by just 2 degrees/kts or so. I have never seen that behavior on any G1000 plane I have flown IRL. 

Just my 2cents.

19 minutes ago, Cpt_Piett said:

I thought that in RL yaw movement due to wind/turbulence was uncommon in the air in general.

Any horisontal gust will exert a force on the airplane empennage. Gusts tends to veer clockwise in N. hemipshere so you can expect both a change in speed and direction of the wind acting on the rudder. Hence yawing motion is to be expected since the acft wants to weather vane. But not as violent as in MSFS in my opinion. 

This is again a difficult topic. Not only has the flight model to be realistic, but we are looking at a static screen, while the plane is moving, because of that also our body and attached head moves within that moving plane but with inertia effects on al axis, AND our eyes can greatly compensate for part of those movements too. If I look at the corners of my monitor, when the plane is accelerating in some axis, the image of parts of the plane should move relative to my monitor edges. Which it mostly (never?) does not. At least not when I was monitoring that behaviour.

And then there is VR. That is even more complicated. Compensating movements of the eyes (saccades etc?) will work differently, but one has to realize that compensating not only runs via a visual pathway, also the vestibular system plays a large role: and we cannot feel how the plane/body moves! (Yes I would definetely love to have a motion platform installed!)

Try watching a video from a fixed cam in a cockpit, it will not be compensated and looks very shaky. On a gimbal already quite different. On pilot's head mounted also different.

(I am a MD, but no neurologist or neuriphysiologist or aviation MD or so and lessons on these subjects I had many many years ago)

Edited November 10, 20223 yr by Rene_Feijen

Hey guys, 

for turbulance in an small aircraft cross check this video (in German, but check plane's  movements) and the first landing (originally I was also wondering about how the Sting behave): 

 

I think the real problem with the current turbulence modeling is specifically the jerky yaw oscillation -- make sure you carefully watch this section of Cpt_Piett's video (starting around 5:20). I'm fine with the other aspects, but this thing needs to be fixed...

I agree. It looks like the plane  is fixed by rubberbands and vibrating within that in 1 plane of motion.

Edited November 10, 20223 yr by Rene_Feijen

6 hours ago, Cpt_Piett said:

I’ve noticed this too. After reading through the “anyone excited about 20km CFD” thread by Abrams (it should really be called “the MSFS word not allowed vs XP word not allowed slugfest), I decided to do a flight in the Sting S4. I thought the constant movement in the yaw axis seems excessive. It was a SU11 flight from KSBA over the hilly terrain, and the Sting has CFD and prop physics in the flight model. 

For some reason I didn’t capture a video flying over the hills, but I got this from the same flight, which shows the aircraft reacting to the surrounding air whilst in a holding pattern over LAX:

The yaw movements are not as pronounced in the video as earlier in the flight, near KSBA. Perhaps the air was calmer over LAX.

I see that MSFS still has the "bomba-deer" ATC problem that exists in FSX and P3D

The excessive side to side turbulence I was experiencing went away when I found a way to deal with the hyper-sensitive rudder axis on my joystick. Now I rarely notice it. This was on the Thrustmaster Airbus stick. If you have one of those it's worth checking that first. 

2 hours ago, SAS443 said:

Any horisontal gust will exert a force on the airplane empennage. Gusts tends to veer clockwise in N. hemipshere so you can expect both a change in speed and direction of the wind acting on the rudder. Hence yawing motion is to be expected since the acft wants to weather vane. But not as violent as in MSFS in my opinion. 

Thanks. I think what we are observing in MSFS is excessive yaw movement even in light wind (turbulence). Like in the video I shared - I can't recall exactly but I think the reported wind strength was less than 10 knots, no gusts. 

3 hours ago, tymk said:

I think the real problem with the current turbulence modeling is specifically the jerky yaw oscillation -- make sure you carefully watch this section of Cpt_Piett's video (starting around 5:20). I'm fine with the other aspects, but this thing needs to be fixed...

Exactly. This type of movement does not make fully sense for me in light winds. It would have been better if I had remembered to enable the shift-z wind speed/direction during the video. Next time...

3 hours ago, Christopher Low said:

I see that MSFS still has the "bomba-deer" ATC problem that exists in FSX and P3D

Haha, yes. And for some reason something strange has happened in SU11 as ATC are using reg. numbers instead of callsigns. 

Edited November 10, 20223 yr by Cpt_Piett