Lack of left turning tendencies
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@Black-Square I wonder if someone has done a battery of focused simulator flight tests on a "Generic Flight model" to identify and catalog what all of these parameters do and how they interact with the CFD physics or not? Sounds like a fun project where you would get to play simulator test pilot.
@Buzz said in Lack of left turning tendencies:
Sounds like a fun project where you would get to play simulator test pilot.
For some of my other work, I have occasionally referenced documents just like this for other parts of the simulator (not aerodynamics) from as far back as FS95. They are all nicely compiled PDF's, or CHM's (if anyone remembers those), clearly created by retired engineers. It seems the mentality that created those isn't as prevalent anymore, or perhaps the systems are just too complex to "make the juice worth the squeeze" now. Be careful what you wish for, haha.
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@Buzz Correct. Not on their own they won't create adverse yaw but coupled with other unique sim-isms and some mildly misbehaving numbers in other areas the configs, you can get visible extremes. For example, combine a wing with too much twist with a plane that has the tendency to skid in a turn and you can get either positive or negative yaw/roll coupling depending on the twist number and direction (and the SDK would lead you to believe the twist works backwards from what it does. Did you know that most helis in the sim have their blades twisted the wrong way and have more aoa at the tips? I digress). Or combine that with a plane that has too little fuselage side area and a tendency to skid in level flight. Or too little yaw stability so it wanders. Or.... well the list goes on. And how the sim handles some of these extremes is less-than-ideal. But the good news is, get those in check and make this number mate up with that number and you get something that flies really, really nice.
This is getting a tad off topic now as I'm not really talking about the Caravan at all with all of the above but flightsim aircraft in general. My favourite was one plane a few years back that would have negative roll coupling to yaw, then when you gently corrected it, it would snap roll the wrong direction.
At any rate, when I can get a minute I'll fire up the sim and see if I can come up with specific recommendations for the Caravan.
@CdnCptMoustache speaking of that, isnt it amazing how the “coding” of nature has everything in order. Such complex systems functioning in a predictable and quantifiable manner without any “bugs”
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@CdnCptMoustache speaking of that, isnt it amazing how the “coding” of nature has everything in order. Such complex systems functioning in a predictable and quantifiable manner without any “bugs”
@django1489 i can think of quite a few bugs in nature I'd squash...
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@CdnCptMoustache any luck on finding a temporary fix?
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@CdnCptMoustache any luck on finding a temporary fix?
@Buzz No, I'm away from my sim gear for most of the next 6 weeks. If I get a weekend back at home I'll give it a shot
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For everyone that wants a hefty left yaw on that aircraft could test the following settings in the configs, until there is an official fix from BlackSquare:
engine.cfg
ThrustAnglesPitchHeading.0 = 0, -6Flight_Model.CFG
rudder_engine_wash_on_roll = 0leave all other parameters as is.
Have fun with lots of right rudder.
Cheers
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For everyone that wants a hefty left yaw on that aircraft could test the following settings in the configs, until there is an official fix from BlackSquare:
engine.cfg
ThrustAnglesPitchHeading.0 = 0, -6Flight_Model.CFG
rudder_engine_wash_on_roll = 0leave all other parameters as is.
Have fun with lots of right rudder.
Cheers
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@Black-Square is this issue going to be fixed in the next update?
@Buzz Yes. JayDee and I appear to have discovered that the ThrustAnglesPitchHeading parameter is interpreted drastically differently between MSFS 2020 and 2024, which has led to some of the confusion. As nobody else has mentioned this on the developer forums yet, I'm hesitant to declare it yet another undocumented change in MSFS 2024, but most aircraft in MSFS don't make use of this parameter at all. The identical values from JayDee above, which are reasonable in MSFS 2024 produce completely unflyable results in MSFS 2020. Without understanding for this disparity, it appears I will be publishing the update with two different values in the two simulators, which is something I like to avoid whenever possible, because you never know when a sim update might break (or reintroduce) parity.
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@Buzz Yes. JayDee and I appear to have discovered that the ThrustAnglesPitchHeading parameter is interpreted drastically differently between MSFS 2020 and 2024, which has led to some of the confusion. As nobody else has mentioned this on the developer forums yet, I'm hesitant to declare it yet another undocumented change in MSFS 2024, but most aircraft in MSFS don't make use of this parameter at all. The identical values from JayDee above, which are reasonable in MSFS 2024 produce completely unflyable results in MSFS 2020. Without understanding for this disparity, it appears I will be publishing the update with two different values in the two simulators, which is something I like to avoid whenever possible, because you never know when a sim update might break (or reintroduce) parity.
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Thank you Jaydee for posting this!
I've been playing around with this, mixing it with the prop_mod_moment_scalar_yaw setting. I'm currently using -4 for the Thrustangle and 2 for the prop moment.
Increasing the prop moment scalar will also increase the "left turn tendency", but will make the aircraft unstable with higher values. By mixing the two, you can tweak how responsive the aircraft is/feels to torque changes.Also worth trying is turning on CFD_ReinjectVTailX and CFD_ReinjectRotors in the flightmodel.cfg. Without this the aircraft will start turning left more, with increasing speed, during the takeoff roll (with the same engine torque). Requiring increasingly more rudder input during the takeoff roll. This seems incorrect, since the rudder effectiveness should increase with increasing airflow, requiring less input.
During rotation it should increase again, because of higher AoA / P-factor increasing.
I haven't had enough time to test this, but it seems to work better with these two settings on.
