50 minutes ago, Rouzbeh said:

 

Interesting

The sparse comments in the linked thread about DCS are spot on based on my experience.

You can definitely fudge factor a bad flight model to make it perform closer to the real thing, but it's difficult even doing it with a programming language when you have full control of all the math, much less in a parameterized table. It can still be done, but it's absolutely no fun, as it requires trial and error over and over again, it can be maddening because it's like balancing an egg on top of another egg and using 4 fans from different angles to try to keep them from falling over. It's not going to be easy. Never done it with a flight model, but have fudge factored a moving target in code before, a dynamic one affected by logarithmic forces, and it is absolutely no fun.

 

Edited January 20, 20215 yr by Alpine Scenery

9 minutes ago, Alpine Scenery said:

You can definitely fudge factor a bad flight model to make it perform closer to the real thing, but it's difficult even doing it with a programming language when you have full control of all the math, much less in a parameterized table. It can still be done, but it's absolutely no fun, as it requires trial and error over and over again, it can be maddening because it's like balancing an egg on top of another egg and using 4 fans from different angles to try to keep them from falling over. It's not going to be easy. Never done it with a flight model, but have fudge factored a moving target in code before, a dynamic one affected by logarithmic forces, and it is absolutely no fun.

 

 

 

 

I have quoted this before but this is what Wing42, the Bleriot developers had to say about MSFS :

 

Quote

Meanwhile, Pamela Brooker took a deep dive into the new flight model, and while some aspects have been improved upon drastically in the new simulator, some other parts of the aerodynamics simulation seem to have been forgotten. The result is a flight model which needs extreme overdamping of the controls and still results in oversensitivity of rudder, elevator and ailerons. Despite those issues, Pamela managed to find a way to get the Blériot XI to conform to her numbers. From an aerodynamics point of view she has created a study-level representation of this iconic 1909 flying machine.

 

Seems right, it would conform to the wider numbers like climb ratio, glide, maybe even basic rudder controls. Beyond that it would probably be quite far off on a more detailed level if you were looking at specific smaller movements between the larger overall numbers.

22 minutes ago, Alpine Scenery said:

 it can be maddening because it's like balancing an egg on top of another egg and using 4 fans from different angles to try to keep them from falling over. It's not going to be easy.

 

Yeah, that's my concern as well.  With a fully table-based system, you define the stability coefficients in each DOF, the lift and draft coefficients in each DOF, etc and you're done.  There are equations for what those coefficients might be for different types of aircraft in Roskam's wonderful 8-volume series on aircraft design. 

With a blade element or point based system like X-Plane or MSFS, first you attempt to make it as close as possible using the blade or point based aero code, which is already a bunch of work.  Then if that's not right, you get tables of fudge factors on top of it and they all interact differently with the underlying aerodynamic model, and you are balancing an egg on an egg with fans.

I'm actually less and less convinced that the blade element or point based method is objectively better the more I think about it.  Perhaps it introduces some emergent behavior that makes things seem more 'alive' in different ways.  Maybe it's "easier" for people who want to play in X-Planes 'Plane Maker' and don't want to have to consult references for what their coefficients might be. 

I do have to think that Bruce Artwick & Co were pretty smart people and they must have considered (and rejected) making big updates to the original Flight Simulator codebase even as PCs became more powerful and X-Plane tried the blade element model. It would be really interesting to pick their brains on the reasoning. 

Edited January 20, 20215 yr by marsman2020

8 hours ago, Chock said:

This is a game which is being developed for the XBox as well as the PC, it's never going to have a flight model you can start logging time on. That's the reality of it.

The reality of it is that most simmers are sitting in a lousy office chair pushing around a cheap joystick, looking at a couple of pixels on a monitor. 

No matter how one wishes it to be otherwise, MSFS is never going to be an "FAA approved training device"; and this is a good thing because then it would cost considerable more than $70.

The purpose of MSFS, IMHO, is to "prime the pump", so to speak, that is, get you interested in aviation. Hopefully some kid is gonna get his butt out of his gaming chair and start taking flying lessons. Or become an ATC, or an engineer. 

I can also see MSFS being a great tool for teaching about cultures and geography, different airlines, etc. 

2 minutes ago, Ricardo41 said:

The reality of it is that most simmers are sitting in a lousy office chair pushing around a cheap joystick, looking at a couple of pixels on a monitor. 

 

 

but but .. stuff like this ...

 

 

Wait a minute! Real pilots having fun with MSFS? Can't have that!

Her entire channel is a nice illustration of the difference between the real world and the armchair discussions that we have here.

People, don't create a new "flight dynamics" myth. For the FS2020 all airplane "flight dynamic" with drag, lift, inertia and etc, inside those two files only - flight_model.cfg and engines.cfg. You need Notepad++,  airplane performance tables, at least basic physics knowledge and couple days to tweak and test your airplane. If you lucky, give it to the real pilot for the final testing. This is more than enough for the $60 game, and yes, FS2020 has the simplest and the most effective way to do this compare to another flight simulators. And please, do not confuse the FS2020 flight dynamics engine with the single airplane flight dynamics files that runs in it. FS2020 flight dynamics engine the best! 😃

Edited January 20, 20215 yr by OSM

So, 20 (30?) years into desktop simulations, and some still get confused? 

 

 

6 hours ago, Ricardo41 said:

The reality of it is that most simmers are sitting in a lousy office chair pushing around a cheap joystick, looking at a couple of pixels on a monitor. 

No matter how one wishes it to be otherwise, MSFS is never going to be an "FAA approved training device"; and this is a good thing because then it would cost considerable more than $70.

The purpose of MSFS, IMHO, is to "prime the pump", so to speak, that is, get you interested in aviation. Hopefully some kid is gonna get his butt out of his gaming chair and start taking flying lessons. Or become an ATC, or an engineer. 

I can also see MSFS being a great tool for teaching about cultures and geography, different airlines, etc. 

Absolutely agree.

Additionally,  FSX had a commercial version (ESP) which became P3D.  I am convinced that Microsoft will eventually launch a commercial version of MFS.  

Microsoft has an Aerodynamics video pending for release, so it'll be interesting to see what has changed and what they intend to change, given community feedback so far.

Edited January 20, 20215 yr by ErichB

12 hours ago, snglecoil said:

Just curious, how much actual experience do you have at the controls of all these aircraft that fly like #%@$ in MSFS? 

Funny you should ask...and I bet you thought you really had something here didn't you?

Baron 58

Cherokee 180 1/2 owner

Bonanza A36

Mooney M20J

Piper Cub

Oops, forgot one - T-6 Texan...but only for an hour.

and you?

As the person who posted the XP11 data to the MSFS forum yesterday, I would like to add that it was not intended in any way to be critical of XP11 or MSFS. Rather it was meant to illustrate the existence of factors that impact our perception of flight simulator behavior that may not be easily expressed in terms of textbook physics. Sitting at home in our lousy desk chairs (as suggested previously in this thread) is very different from being in the cockpit of a 172 at 2000 feet as a cold front bears down on you. We're now talking not so much about inertia as we are about gestalt (there's a word you don't see often in flight sim forums 🙂), and so it is our perceptions that matter, as well as the POH numbers.

A flight model that allowed designers to hit with precision all the V speeds, fuel consumption, and glide ratios, might be perceived as providing an "on rails" experience. MSFS appears to be reaching beyond the POH to provide that holistic experience (still in those lousy chairs) by reaching for those emergent properties, and IMO, to some extent that has been achieved, even at this early stage in the sim's development. But there's a long way to go, yet, to achieve the results that we all wish to see. Good luck to MS/A and the 3PD in leading us on that journey.

Best wishes to all.

4 hours ago, somiller said:

Funny you should ask...and I bet you thought you really had something here didn't you?

Baron 58

Cherokee 180 1/2 owner

Bonanza A36

Mooney M20J

Piper Cub

Oops, forgot one - T-6 Texan...but only for an hour.

and you?

No, it's the reason I asked. Most of the comments are (understandably) from people whose experience is limited to whatever sim they have been using. 

As far as my bonafides, I have PIC in a 7AC, J3, C152, C172, C182RG, BE36, and a BE55 Of those, most of my "pilot flying" PIC (not including dual given) is in the 172. I teach instruments based on PACs - Power, Attitude, Configuration - for a known power, pitch, and configuration you will get predictable performance.  So in a 172 for example, you will get a precision approach descent of 500 fpm at 90 kts if you set 1800 RPM and about a 1 ball width nose low attitude, flaps up. (adjusting for variances for the specific plane you are flying) 

The MSFS C172 is by far the most faithful to the generic "numbers" in all phases of flight of any I've ever used in any other sim. A2A's is second...and X-plane's 172 is shockingly bad.

Is the BE58 any good? ...Well based on the slightly lower powered BE55 that I used in my multi-engine training, it seems off, but then again it has extra horsepower and I've heard experienced BE58 pilots say that it is not as off as I think it is. What IS off is the fact that they haven't bothered to include prop feathering. I'd like to see that fixed.

Is the King Air good in MSFS? Don't know. I have no experience, 

Is the TBM? Don't know. I have no experience

208? A320? SR22? X-Cub? Don't know - you get the idea.

So to whip out a huge brush and paint everything with regard to the flight model the color of #%@$ is just not my experience. But you are certainly entitled to your opinion. I still hold that this quest for the flight model Holy Grail is a largely wasted effort in a desktop sim. There is room for improvement with MSFS, but using all 3 major sims now, I'd say MSFS is definitely on the right track.

Edited January 20, 20215 yr by snglecoil
Edited for clarity

@jrw4, beautifully stated!

Edited January 20, 20215 yr by snglecoil