Ah I get what you mean now. Agreed, I thought so too!
Well, my opinion: marketing slogans are lies in a nice packaging. As long as Asobo does not officially sign the statement: “FS2020 is fully and only based on fluid mechanics using the Navier Stokes equations” I think they use a hybrid model.
But now to business. The airplane geometry is told to the simulator in section [AIRPLANE_GEOMETRY]. But this is very elementary. After giving values in this section, the airpalne can fly. But normally you are not satisfied with the flight behavior, e.g. the real airplane does react more sensitive or less sensitive to aileron. Aerobatics airplane react more sensitive. Now you could fiddle at aileron_area to make - in the model - the aileron larger. More intelligent is to use section [FLIGHT_TUNING] and increase aileron_effectiveness. The “numerical integration beast” uses aileron_area and aileron_effectiveness together to calculate the variable that really controls the flight model.
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I took the time to watch the video. The Asobo CEO says: “So the integration is now super realistic. It’s exactly moving the aircraft as they should in the world”. Okay, this is the marketing statement.
But now I talk about configuration parameter work I do right now. The picture shows the polar curve of LS 4. But all polar curves look the same. It looks like a hill. You have the hill top and left and right you have a slope. The hill top is minimum drag. If you go slower or faster you have more drag. I can simulate the right slope - more speed results in more drag, but I can not simulate the left slope - less speed results in more drag. By the way, FSX could not simulate the left slope either.
Some people call the left slope “lift drag” and the right slope “parasitic drag” and teach it on Youtube. See https://www.youtube.com/watch?v=I0c9eY9kU68
I say “this is elementary, Dr. Watson”. No wonder that real pilots say the simulator is harder to fly then an real airplane.
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I have teached ATPL Principles of Flight and ATPL Performance for years so I’m familiar with aerodynamics, lift / drag curves, speed stability etc. I’m have no knowledge how the FS2020 flight model works, I thought I had some idea as the Asobo video implies it is somehow physics based with “1000 simulated surfaces” and what not but apparently it is not…
So if you can’t simulate the drag curve properly this also means there is no possibillity to simulate speed instability i.e. “back side of the drag curve”?
Don’t get me wrong! Since two days I really believe that the FS2020 has more potential then Flight Unlimited, the fluid mechanics based work of Seamus Blackley. But at the moment in some areas FS2020 is as limited as FSX is.
I won’t start the “no thermals” topic.
The left slope in the polar curve is the “back side of the drag curve”. Maybe Asobo/Microsoft have some hard-coded trick that “kicks in” by a trigger (flaps down?) to simulate the back side. But this feels very artificial if you can not model it on a per airplane basis.
As a former flight instructor I wish all my C152s were as powerful as the one in MSFS2020 
But it gives you a very nice impression on how a stall works, for example. Way better than previous simulators did. It’s really hard to translate the real feeling into a simulator where you can’t feel the engine vibrations or the wind.
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The problem is that non of us FDE oldtimers who are developing flight models for sims like FSX and x-plane since decades have presently any idea how FDM design in MSFS precisely works.
It’s still pretty much unclear which data a read by MSFS and which are computed. Significant basic changes to the FDM are presently impossible.
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Hi, I’m not a real pilot, but I believe it’s wrong what you are saying.
A German newspapern puplished a report written from a real pilot.
It’s in German sorry. He writes, like many other people too, that there is not a single plane with a realistic flight model. Why are so many mods out there? Even when I look what the Tbm930 does in the new version, compared the last version I’msure there a lot’s of bugs in this particular plane. I had a look into the original tbm930 manual, especially to the autopilot, the actual version of msfs2020 is doing stupid things. In the moment fs2020 is a super game, with fantastic graphics, but far away from a simulation.
Reiner
Example: There is a new FS2020 parameter best_glide in [REFERENCE SPEEDS] What does the documentation say? It says “Best Glide (Kts)”.
It is possible that drag below best_glide increases by some average number. This would be an improvement over FSX. Maybe the parameter is available, but no “machinery” is behind, the parameter is ignored. Or the machinery is doing something different like light a lamp in the cockpit: “You have best glide”.
How does this work with different weights? Different weights mean different min. drag speeds, is there a way to model this?
Well, as PZL104 said, we configuration editors are on a learning curve here. My opinion: do not expect miracles. As you fly, fuel is used and the center of gravity (CG) can shift. This should impact the flight model. I don’t know if it does!
There is a difference between having the CG at 25% MAC versus 50% MAC at the start of the flight. But this is - maybe - only computed at the start of the flight and never updated as you consume fuel and shift the CG.
When you roll it sounds like they didn’t lock some cargo down in the forward hold!
I wonder if that’s exactly what happened when they recorded them? Maybe they just rolled around the airport…
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I think MSFS simulates physics by using air simulation sorta like XP does (it’s different tho) and then tweaks that model using the .cfg files.
Correct me if I’m wrong tho
Real world airline pilot here, with 10 years of GA experience on the side.
Absolutely love the graphic detail and immersion of the sim but agree with others about the flight models being overly sensitive.
I’m using a Logitech Extreme 3D Pro joystick and have been continuously experimenting with reducing in sensitivity of the X,Y and Z axes to make the GA craft feel more realistic to control. Of course without the weight on the yoke that you feel in the real world from wing loading, this is never going to be like the real thing, however with FSUPIC 7, have made some headway to prevent my over controlling tendancy.
In the real world, as well as in previous sims, the most satisfying aspect of a flight is a smooth touchdown. It seems almost impossible to achieve this in FS2020 at the moment, as the control surfaces seem to have a rapid acceleration towards the edge of the axis scale, particularly in the pitch axis during low speed flight. Small and deliberate control movements are required to prevent large jumps in nose up input, where as with less airflow over the elevators during the landing phase, this should not occur. In the real world, you can make larger more abrupt control inputs at slower speed with lesser effect noticed.
If this can be fixed in the future, it will really up the enjoyment factor for me. For now, I’m having to fly flatter than standard approach profiles and land faster, with more power on than I would in the real world to prevent nasty pitch ups at the last second.
I also frequently experience a large yawing motion just prior to touchdown- not sure if this is the real world weather data switching between meteoblue and the local airfield METAR data and causing a wind shift, or is ground effect is just modeled in this way. Rather annoying to experience after a long smooth flight with light winds loaded.
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As a not real pilot there are two things that bug me about the FM. One is the lack of adverse yaw, so you don’t need rudder when you enter a turn and the control authority is the other. I have very little real flying experience but it’s clear just from watching videos of real landings how much control movement is used compared to the very small amount in the sim.
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Yes, sir, I believe you. But the simulator … The FS2020 has a new section [AERODYNAMICS]. There are lots of non or badly documented parameter. Maybe there is a parameter that can exactly do what you want. But again:
- Asobo did not use these parameters, I think because there was no time
- We have no documentation, specially not about how parameters interact
- And maybe the parameter is there, but no machinery behind the parameter
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I am an armchair pilot. But even I recognize the difference between the real flight instructor videos on Youtube and FS2020.
Because I have no rudder, only a Xbox controller, I am happy about not needing the rudder.
If I look at the ball (turning instrument) I see that using rudder makes a difference. Without rudder, ball is somewhere, no corrdinated turn. With rudder, ball stays in the middle, coordinated turn.
I don’t know if there is some “rudder automatic” . But I like to switch it off. If necessary you can load one mod without rudder automatic and the other with rudder automatic.
You need to use the rudder to enter a turn. Here’s a short article about the turn coordinator in nearly every “steam gauge” aircraft.
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Hello Tacot37. Cap10 mod version 1.1.1 is out at http://www.andreadrian.de/FS_2020_sailplanes/index.html
I tried to give the Cap10 and the other aerobatics airplane a (more) realistic sink rate, that the planes want to touch-down. Sink rate is 1000 feet per minute (fpm) at 76 KIAS and 1200 fpm with flaps full down. Flaps is the trigger to get Lift drag. Furthermore I gave them (more) realistic cruise speed. At level flight in still air, the Cap10 should now only do 127 KIAS.
Another real pilot wrote about “I need no rudder”. Can you tell me how realistic/not-realistic is the rudder behavior of the simulated Cap10 for you?
What do you mean by “you need to use the rudder to enter a turn” you enter a turn by use of aileron input, only using the rudder for coordinated flight. Sure yaw will cause roll but that is not the proper way to enter a turn.
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