3 hours ago, robert young said:

If you look through the flight model configs in the simobjects folder, you'll see clearly three things: 1) The inertias of almost all the aircraft are set at ludicrously low values. 2) The pitch stability params are set far too low 3) The control surface authority params are set way too high. In another post I have observed that the Bonanza maximum roll rate in this sim is equivalent to a high performance aircraft. It is way too strong.

 

Just so we are on the same page, it sounds like you're saying that when you looked into the different airplanes configs, you found those three things to be TUNED wrong for each airplane. 

Does this mean that we can go in an edit said parameters?

If we can go into the config files and edit them ourselves, the problem lies with how the airplanes were tuned and not the actual modeling of flight within the software. Is this a correct assumption?

Just now, ahsmatt7 said:

Just so we are on the same page, it sounds like you're saying that when you looked into the different airplanes configs, you found those three things to be TUNED wrong for each airplane. 

Does this mean that we can go in an edit said parameters?

If we can go into the config files and edit them ourselves, the problem lies with how the airplanes were tuned and not the actual modeling of flight within the software. Is this a correct assumption?

I would urge caution on this. You need to make a rock solid backup of the flight model cfg file and place it for safety in another folder well away from the sim. The params in that file are not at all straightforward and they've added some new stuff, while getting rid of others. The lift and moment data is differently presented from what I'm used to so it will be a long learning process.

But you could safely tweak the "flight tuning" section which has fairly easy to implement and somewhat global controls over stability, drag, lift etc. But I think things are more complicated than that. There are probably tparamaters outside of the flight model which affect the aircraft, the most obvious being air mass, winds, gusts etc.

Tweaking the aerodynamics on this sim is far less straightforward than past sims, not because there is anything new (apart from maybe the weather influence) but the syntax and descriptions are not obvious.

7 minutes ago, robert young said:

I would urge caution on this. You need to make a rock solid backup of the flight model cfg file and place it for safety in another folder well away from the sim. The params in that file are not at all straightforward and they've added some new stuff, while getting rid of others. The lift and moment data is differently presented from what I'm used to so it will be a long learning process.

But you could safely tweak the "flight tuning" section which has fairly easy to implement and somewhat global controls over stability, drag, lift etc. But I think things are more complicated than that. There are probably tparamaters outside of the flight model which affect the aircraft, the most obvious being air mass, winds, gusts etc.

Tweaking the aerodynamics on this sim is far less straightforward than past sims, not because there is anything new (apart from maybe the weather influence) but the syntax and descriptions are not obvious.

Does the SDK contain any information about the model cfg data, e.g. how to edit it, what the various parameters do, etc.?

I'll be very disappointed if we can't edit the specs and settings ourselves.

Dave

Edited August 19, 20205 yr by dave2013

Can we all agree that by default a control input like a joystick axis, or a yoke axis, or a throttle, sends out a number via USB to the PC. This number usually ranges from 0-1023, but other ranges are possible, like 0-127 or 0-511.

So ... full deflection of the rudder pedal to the left sends a 0 and full deflection to the right sends 1023.

In the Windows control panel we have 'printers and devices' where we look for our controller and we calibrate it. We see the x,y cross move, or the bars for throttle and other axis. They need to be calibrated there first ... only then Windows knows what numbers to expect (0-127 or 0-1023) and translates this internally to the Windows default min and max values.

Up to here, all linear.

To stay with the rudder ... when we just calibrated the input in the Windows control panel, full deflection left right should result in a visual full deflection of the rudder, bot the pedals in the virtual cockpit, but more importantly ... the rudder on the back of the plane.

If someone who has MSF running could use an outside camera to have a look at the rudder and how it moves with controller input from full left to right ... then we know.

How (fast) the plane reacts to that deflection ... that depends on the flight model and the plane inertia. If it feels too twitchy our 'workaround' is to change the controller sensitivity ... but it is no more than that ... a workaround.

And I am very curious if the sensitivity curve in MSF is lowered (which makes the shape sort of exponential) how the actual rudder deflection responds. Is it now also exponential, as in the beginning the movement is less than linear but further to the end it much more than linear? Or is it a timing, the rudder reacts slower to our inputs?

Edited August 19, 20205 yr by RudyB24

3 minutes ago, dave2013 said:

Does the SDK contain any information about the model cfg data, e.g. how to edit it, what the various parameters do, etc.?

I'll be very disappointed if we can't edit the specs and settings ourselves.

Dave

I haven't downloaded the SDK. But if it is anything like previous SDks you get something like this:

parameter 201: sideslip on yaw  --- Explanation: This parameter adjusts sideslip on yaw

That's how helpful most aircraft container SDKs are!!!

3 minutes ago, RudyB24 said:

And I am very curious if the sensitivity curve in MSF is lowered (which makes the shape sort of exponential) how the actual rudder deflection responds. Is it a time delay, or is it actual deflection?

In p3d and FSX it is most definitely a time delay only. There are no exponential or other curves. In FS2020 I'm not so sure it is time delay. It looks like direct manipulation of the available travel, which is common in a lot of other games and sims, especially racing sims.

Robert, if I understood right you have MSF running ... have you looked at rudder deflection with a rearview camera? Does it move linear from left to right, linear with pedal or joystick deflection?

I won't say a best fix - but an option is to cut off full travel and to then mirror 1:1.  Maybe that can be done in config? It would certainly have other limitations, but for that 4" of travel pulling back on Yoke could then theoretically perfectly match a given aircraft.  The tradeoff is that if the real plane travels 9", you lose that ability.  I'm of the mindset that if you can't have equipment that is highly accurate on travel, then you are just chasing solutions with bandaids.  Some will be better than others, but you will never be perfect or really that close to it, especially at the further travel limits.

After hearing Roberts explanation and answer to my questions I asked him. It looks like it's very apparent that the airplanes weren't tuned right. If this is truly the case, then 3rd party add on developers will do what they do and give us much better airplanes just like in past Sims.

The same thing will happen, the default airplanes will stay in the hangar as new more finely tuned airplanes are put into the market. 

After hearing Roberts explanation, I'm not worried at all about the flight model anymore because I know smarter people than me will learn how take advantage of the newer flight model.

I'm with Rob Young on this.  I've been saying for a while that the proof of the pudding with this new FDE is going to be in the tasting, and so far Asobo has given us *nothing* in the way of flight dynamics that suggests in any way that their flight model is superior to, or even at-par with the previous iterations of flight sims.  In the last 36 hours I've flown the MSFS SR-22, the DA-62, the C208, the BE-350i and the Citation Longitude, and I'm sorry to say that none of them behaves like I'd expect an acft of their class to behave.  I am not talking about nit-picking whether they fly right on the numbers...I am talking about big, in-your-face problems, like the 350i flying down final with gear and 50% flaps at flight idle and unable to slow below 135 KIAS, like massive pitch changes in pretty much all of them when the flaps are retracted or extended, and the hugely oversensitive control axes--like an elevator axis that can produce a 30 deg nose-up pitch change in less than a second with 50% control input 20 KIAS above stall speed in the DA-62.  C'mon, that's just absurd.  The FDE are a huge miss...they are not favorably showcasing their new flight dynamics model with the default fleet as released. That's not to say there isn't something positive in how they're doing things...but so far I honestly cannot see it, and it's results that I'm looking for.  The platitudes about not expecting anything but the worst from a default acft don't help. 

I've tried tweaking the flight_model.cfg on the DA-62 to try and calm down the wild pitch overcontrol and instability problems, and so far it appears that none of the changes to that file are affecting the flight model behavior--I've tried the flight tuning settings, changing pitch moment values, elevator area etc to no avail--I wonder if the cfg file is being used or if the parameters are coded somewhere other than the Simobjects\Airplanes folder in the package.  Those problems are not input device issues, either--they were experienced with an assortment of different control devices including TM Warthog, Cougar, and T.16000M sticks and a custom PFC yoke.  I use tools that monitor the raw inputs made by the HID devices to the computer.  A normal range of control inputs is producing an abnormal range of control responses, plain and simple.  The large amount of rapid attitude translation experienced when applying a modest 20-30% elevator control input is not in any way realistic, and de-linearizing the controller input curve doesn't change the fact that small control movements are producing inconceivably large and abrupt control responses in these flight models.  They are really, really flawed as they exist now.

I'm kind of surprised at how much hostility Rob is getting over this--he's a well-known FDE designer that has produced some of the best models we've seen in FSX/P3D.  He's a bona-fide expert on this stuff, and no, he's not wrong here.

 

10 minutes ago, w6kd said:

I've tried tweaking the flight_model.cfg on the DA-62 to try and calm down the wild pitch overcontrol and instability problems, and so far it appears that none of the changes to that file are affecting the flight model behavior--I've tried the flight tuning settings, changing pitch moment values, elevator area etc to no avail--I wonder if the cfg file is being used or if the parameters are coded somewhere other than the Simobjects\Airplanes folder in the package.

I think this file may be for backwards compatibility (the second flight model mode in the sim) rather than the new engine.

Perhaps the extreme control sensitivity is intended for Xbox controllers rather than PC joysticks?

1 hour ago, robert young said:

I haven't downloaded the SDK. But if it is anything like previous SDks you get something like this:

parameter 201: sideslip on yaw  --- Explanation: This parameter adjusts sideslip on yaw

That's how helpful most aircraft container SDKs are!!!

Yeah, I know what you mean.  I have always had to make adjustments to the MOIs, and tweak the flap scalars as the flap effects are usually exaggerated, on most default and other freeware aircraft.

We have had the same aircraft flight dynamics since FS2000, or maybe even FS98, roughly 20 years.  That was a lot of time for folks to figure out how things work, what effects changing this and that has, etc. 

It looks like we all have a lot to learn with this new sim.

Dave

Edited August 19, 20205 yr by dave2013

Very good thread.  Thanks @robert young for that great info as usual.

28 minutes ago, w6kd said:

I'm kind of surprised at how much hostility Rob is getting over this--he's a well-known FDE designer that has produced some of the best models we've seen in FSX/P3D.  He's a bona-fide expert on this stuff, and no, he's not wrong here.

 

Thanks Bob. I appreciate that. I try not to get stressed but there have been a lot of post that dismiss out of hand what I, and others, have been saying. I think you are absolutely right, and eloquent, to say that the proof is in the tasting. I try to not read any marketing stuff before trying something (though that's hard to avoid). I just fly the machine and think "hang on, that doesn't match anything I experienced in the real aircraft", or similar aircraft. I think a very telling part of this is that when doing an approach, if it is actually easier in the real aircraft than the simulated one, then something is wrong.

After a few years in this game, you can tell almost within seconds of taking off that it doesn't feel right. What is disappointing is that in their understandable enthusiasm to cheerlead this sim onwards, I honestly think some comments are either spell-bound or somehow choose to ignore the blindingly obvious.

I took the C172 for a flight earlier, and I was dumfounded at how unrelated to any real c172 I've been in it was. Every single input, control, every jerk, twitch and bounce was so removed from reality it is just incredible that anyone could possibly describe this as "authentic". I am coming to the conclusion that many simmers believe that an aircraft is only authentic if it is impossible to control. ALL aircraft are hard to control in extreme weather, or big cross winds, or when landing in inclement weather. But why should any aircraft be almost uncontrollable in benign conditions? They are designed to be stable, to not deliver surprises. The C172s of this world are specifically designed to be the most ;pilot-friendly, agreeable aircraft on the planet, That is why they are so successful and why thousands of flight schools buy them.

Even in challenging conditions they do not buck up and down in pitch, nor do they yaw 50 degrees from left to right in less than a third of a second. They are designed to be stable, and they are.

Best Wishes.

 

Ok i have a question.  After seeing all this talk about what a perfect flight model/behaving aircraft should be, has any sim thats available right now pulled it off? Please let me know the sim and the aircraft that is perfectly modeled because I would like try it out, or does that not exist? I genuinely would like to know, not trying to be smart or take shots at anyone.