More Physics, More Real Winds

Try as I might I just don’t like X-Plane, and before MSFS came along I would spend most of my time in P3D.

the problem I feel with X-Plane is not systems related but the pure stick feel, and while MSFS lacks in system modelling in comparison to both P3D and X-Plane, the stick feel at the exclusion of all other things of P3D and MSFS feel closer to one another, with X-Plane as the out layer.

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Correct is a broad term, but in theory X-Plane should be “more” correct.

The main difference between Microsoft Flight Simulator and X-Plane is, that the latter determines the aerodynamic properties of an aircraft from how it is shaped and what kind of propulsion it has, while the former just looks up the aerodynamics from tables that can be complete fantasy. It all depends on the developer providing the correct numbers.

That is why you can create a flying doughnut in FS2020, but not in X-Plane.

As far as I know, FS2020 also lacks many or any propeller physics, while X-Plane has them. Of course X-Plane also simplifies the calculations required at some juncture, but according to LR it is a more robust system.

Considering that the X-Plane approach managed to create a realistic Mars atmosphere many years ago, maybe there is something to it. Sure FS2020 has a lot more data points compared to FSX, but the basic principle is the same. If the developer of a plane uses false data, the sim will just use that without asking.

In X-Plane, when an aircraft is shaped correctly (important to have a correct 3D model), the physics will be empirically sound, thanks to Blade Element Theory.

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That’s a given, because P3D and MSFS use the same type of physics modeling while X-Plane does not.

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Msfs does not use lookup tables (unless you enable the legacy flight model)

Only fsx and P3D do.

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That was my understanding as well. I was actually searching trying to find the official statement but can’t find it again. Do you have a link?

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the fact that MSFS can have a flying doughnut and X-Plane cant per se doesn’t mean at all that X-Plane is any better or worse, its is just they use different methods to achieve the same thing.

the problem with the X-Plane method is ANY small errata in the underlaying Blade Element Theory has a global effect, likewise if it was really that good at what it dose, the arguments of X-Plane vs. P3D would have been done and dusted years ago, but as we ALL know that is NOT the case with many many IRL pilots preferring P3D over X-Plane as the former produces better flying results.

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Can you please show me, like the example in my video?

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Only X-planes flight model isnt all that great. Flew on X plane earlier and the turbulence effects only suddenly kicked in on approach as I came down the last few thousand feet. The rest of the time felt like being mostly on rails.

With a little polish the flight model on MSFS will be far better.

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The Turbulence effects are there you, just need to define the altitude. But if you show me with a video, I will check it, and show you how to set it up.

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What is your source on that? As far as I’ve understood MSFS doesn’t use lookup tables (at least with the Modern flight model). They’ve included the ‘Legacy’ flight model for backwards compatibility (which does use lookup tables). Pretty sure the flying donut uses that legacy model.

The legacy model is crap. .The modern model is based on calculations over the wing surfaces.

screenshot taken from:

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i don’t think laminar can make something even close to what msfs is doing rn. It will only get better

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also the flight model in msfs can be great if configured properly. It uses the aircraft geometry and the wings to make the flight model, but it also uses tables for certain properties because geometry is never perfect. It still needs improvement, but it’s already in an ok state

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Thank you for your feedback, I would really love to see your flying with FS2020, and land the plane with 80 degrees cross wind at 23 knots, and 46 gusting wind. It would make me very happy, Everyone here should learn from the physics you understand and apply.

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Why would it make you happy? It might be simpler if you wrote plainly what you aim to prove here.

Nice landing in the video by the way, although the final looked a bit wobbly. The engines in reverse reminded me of my heat gun that I use when roasting coffee. :slight_smile:

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It does use lines of code from the .cfg file, even for the “modern” flight model. The flight model is different from X-plane. The X-plane flight model is the more realistic approach, calculating everything on the 3D model. Depending on how good the 3D model is of course. In my opinion X-plane more closely represents reality, its not perfect but propeller effects etc. are all simulated and reasonably accurate and most of all, not dumbed down. In one of the developer QAs they said the slipstream effect was tuned down because they believed users “wouldn’t understand why the aircraft would yaw to one side, they expect the aircraft to go straight like in the car”. Thats their approach towards developing an accurate flight model…

Maybe third party devs are able to reach a greater level of realism with this approach as compared to X-plane, but the default MSFS planes are so far not a very great showcase for their flight model. The atmospheric model isn’t that great either (true altitude for example not affected by temperature), systems, autopilots etc. not working or having bad logics. So far the only thing great about it are the graphics.

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I’m not saying you’re incorrect, but I’ve seen this stated multiple times, but never seen a credible source on this.

If you’ve got a source, then please share it.

If the source is ‘those lines exist in the CFG file’, then consider that the modern planes have to work for people who set ‘legacy’ as well, so maybe those lines were included just for that? Unsure.

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Easy, just look at the recent bug regarding the wrong flap modelling, their workaround is to open the .cfg file and change some values (divide by 2), isn’t that the evidence you are looking for?

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Yeah, and most aircraft mods will tweak this file in particular to, hopefully, better model reality.

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Nope, it’s not.

I can understand they use some scalars to increase/decrease certain effects. This does (at least in my opinion) not prove that they’re using a lookup table for all those thousands of points along the surface of a wing (like in the screenshot I posted above).

Again, I only see a lot of people jumping to conclusions based on partial information at best, and stating it as fact.

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I’m not saying everything is coming from the .cfg file but its not like the X-plane flight model either (everything based of the 3d model), as I understand the 1000 of surfaces etc. are used to calculate how the aircraft reacts to the environment, wind, turbulence etc. I’m not a programmer, I can only argue based on my knowledge about aerodynamics from being a classroom instructor and pilot. In the last aerodynamics video there are still numerous of inaccuracies if you look closely.

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