Flight Dynamics: FSX and X-Plane battle it out

[AchillesP]

I found this article. It explains the differences between fsx and x-plane flight dynamics.

http://www.simpilotnet.com/index.php?option=com_content&task=view&id=20

[Trevor Hale]

Very interesting and informative reading :)

Cheers

[IanH1960]

Hi,

Also worth reading is Austin's reply to some of the issues raised in the article.

http://games.groups.yahoo.com/group/xplane-news/message/1412

Ian

[Paul G]

I have to say that I find X-Plane most unrealistic. Technically it should be way superior but every simulator I've been on that is based on X-Plane I've felt my education is more focused on X-Plane UI than on flying. And I'm a real pilot so would know.

[BlackWidow]

WOW that is some good reading

Now Im even more confused LOL.

[mauriceb]

My X-plane 'experience' dates back several years, so may not be relevant anymore. But at that time, I thought X-plane was great. However, I never tried the one test which I think would separate the men from the boys and which both FSX & X-plane fail miserably according to this article.

And I'm referring to the cross-control situation which you can use to lose altitude fast without gaining speed (or for crosswind landings). The FSX 172 (& I'm sure other models) fails very badly and is totally unrealistic. If you lower a wing, you will start turning no matter how much opposite rudder you use. From my past experience, I thought X-plane would be better but this gentleman claims X-plane is not any better.

If that is true, then I would say all the hype about X-plane flight model is just hype. Has anyone tried this with X-plane?

Maurice

[Tomlin]

This article pointed out something that I have always wondered. If X Plane's aircraft fly according to the way they are built, using geometry and BET, then why does the default C172 fly so horrible? I'll give them that the article (or response to the aforementioned article) admits that the 172 is not their 'strongest' aircraft (Im not able to find that quote now, sorry). However, if the aircraft fly according to how they are built in the sim's environment then evidently the default XP C172 was not made very well. It's a long debated topic, but certainly worth revisiting from time to time since the lastest version does look very nice compared to a few versions back. My experience with ver. 8 is where I got my personal reference from.

Thanks for the post.

[ganeshan]

Worlds costliest flight was Airbus its more attractive when compared to other flights flight dynamic it will be good.
--------------------
Ganeshan


Sreevysh Corp (http://www.sreevyshcorp)

[Paul G]

...if the aircraft fly according to how they are built in the sim's environment then evidently the default XP C172 was not made very well.

I think this is the golden point. If your basic model for creating an aircraft is based on real flight dynamics, either you spend months creating a technically accurate model with the risk that a small error will mess up the whole experience, or you approximate it.

Now here's the other thing. A vast majority of after-market X-Plane aircraft are from enthusiasts, and appear to be for free. While this is no bad thing, how many contributors will invest this time painstakingly tweaking their dynamics?!

Having a model that accurately reflects flight characteristics has the potential to be the best and most useful flight simulator on the market. The question, in my mind, is of the fidelity of the in-built and public domain aircraft.

With the Microsoft model, not needing a Ph,D in aerodynamics coupled with an apprenticeship in advanced fluid mechanics, means that it's quick and easy to build aircraft that will either closely resemble the original for 90% of performance and handling, or will be easy for someone else to come along and tweak.

In theory X-Plane has the potential to be the best flight sim, but in a practical sense Microsoft has the upper hand

[AndyT]

Another point,

Austin says that 10 or 100,000 polys makes no difference in the handling and he should know because he tested it he says.

That's true as far as it goes. What he doesn't say is that the engine is not designed for that level of resolution when computing the dynamics during flight. If it were, then more polys would equal more accurate flight characteristics.

Another thing that is not taken into account is the wear and tear on the plane and especially the engine. As a plane gets older, it loses power. Put a new engine in and get your performance back. Are we to model aging engines now as well?

If only I had a copy of FS20. I have no idea what kind of machine it will require but I bet all this will be quite moot by then. Hmm... Thats in about 25 years from now... I might live to see that.

[AchillesP]

If only I had a copy of FS20. I have no idea what kind of machine it will require but I bet all this will be quite moot by then. Hmm... Thats in about 25 years from now... I might live to see that.

The engine parameters are inside .air file. Until now fspassagers can create a failure if you do not servive the airplane. So, why next version not to edit .air file automatic for engine loss of power due to years old? It is not a big deal. Can be done. But it depends from the request's they will recieve.

[rt72]

Austin;s X-Plane was initially designed for testing prototype aircraft that hadn't been built yet.

It's a good approximation of a plane's potential, but comparing thr real-world 172 to the X-Plane one, the model is flawed for existing aircraft.

[WJH308]

One simple test I always do with any flight sim, is to see how it models P-factor. High angle of attack, and that damn ball stays centered in a prop airplane... X-plane and FS9, FSX fail horribly at this. One reason I went with X-plane is because I simply can not stand how FS9/X handle cross wind landings and watching my airplane go down the runway crabbed into the wind long after touchdown. I am sorry, that annoys me so horribly.
At the end of the day, a sim is mainly a procedures trainer. FS9/X and X-plane without question are best used for simulating and practicing instrument flight and procedures. Without question.

[Paul G]

FS9/X and X-plane without question are best used for simulating and practicing instrument flight and procedures. Without question.

You're right. You can learn where things are in the cockpit so also excellent for checklist items for the main panels. You can learn about how systems work a little. You can even learn systems like the G1000 or flight management computers if faithfully reproduced. You can learn basic American VFR ATC procedures, and as you say Instrument flying (though not so much the communciation experience as SIDS, STARS and airways are not supported by base).

But there's a good reason why the pros use (real) Level D simulators and hands on flying on flights with passengers. At least for now...