Could you imagin

[dmaher 0]

Actually they don't. X Plane uses Blade Element Theory (BET), which was originally developed to try and settle arguments about whether paddle steamers were either more or less efficient than ships with underwater screws. BET calculates the forces generated by shapes, which means X-plane reads the shapes of its 3D objects and then calculates how they will act in a fluid (air in the case of X-Plane of course).FSX is completely different, in using 'look up tables' to determine the effect of values in the aircraft configuration files, which it then translates into how the aeroplane should fly, so the 3D model itself has no bearing on how it acts in the sim.You'll get a lot of arguments over which one would be more accurate or flexible, they both have plus points. Of course if you drill right down into all that, both sims do eventually have to emulate the laws of aerodynamics, lift, weight, drag etc, but they get there by very different routes, as far as the computing aspects go.Al

Thanks Al, I see. I was actually aware of Xplane’s use of 3d geometric aerodynamic models – but I thought they were moving away from for some reason. But you tell me, the geometric models are used to generate the data. That data, I suspect, goes into standard Roskam's equations. You could use AVL (too slow for realtime) to do the same to generate FSX tables - I've tried this. And this process is used in at least one professional prototyping sim I've found, so it works. Xplane has a more user friendly processes...but it doesn’t follow that the core has better potential. The process is different, yes. Getting tables correct by hand is harder but there is no intermediate geometry that must be interpreted by code (sometimes incorrectly or primitively). I had a long talk with Xplane at Oshkosh years ago….trying to convince them that the visual geo and the dynamics geo needed to be separate – each limited the other. They weren’t pleased – but I don’t blame them – it’s Oshkosh ;) and I was all enthusiasm and no tact, so maybe a jerk :( Again I haven’t tried Xplane, but because building an accurate geometric model is more intuitive, I think the Xplane process will make the average flight model better. But hand editing the tables directly in MSFS produces a more refined and subtle flight model in the hands of an expert…like realAir. And I’m absolutely convinced using tables directly is better for hardcore users - if there's any doubt ;)Dannyand...Go Canucks Go!

[Chock 17,769]

I agree, I bought X-Plane some time ago to give it a shot, but to be brutally honest, I wasn't hugely impressed with the flight dynamics it created. Although BET sounded brilliant in theory to me, in practice it appeared to only be a basis upon which to start further refining things, and if one has to do that, I felt that I might as well have been doing it from charts in the first place in the manner that FS does.Of course X-Plane has developed considerably over the years, so all that may very well have improved and I daresay it has, but I'm awaiting the reports of version ten before I'll commit to it again.Al

[Tierborn 188]

I agree, I bought X-Plane some time ago to give it a shot, but to be brutally honest, I wasn't hugely impressed with the flight dynamics it created. Although BET sounded brilliant in theory to me, in practice it appeared to only be a basis upon which to start further refining things, and if one has to do that, I felt that I might as well have been doing it from charts in the first place in the manner that FS does.Of course X-Plane has developed considerably over the years, so all that may very well have improved and I daresay it has, but I'm awaiting the reports of version ten before I'll commit to it again.Al

no real improvement ..... in comparison to MSFS 

[Gibbage 199]

I personally have always wanted to model for Xplane. It sounds so promising in the fact that the FM is partly calculated by the way the aircraft is shaped. Its a modelers dream! The only problem is, the dev's make 3rd party life a living nightmare with constant updates that brake 3rd party aircraft. So even after you release a product, you CONSTANTLY need to do updates for almost every version, and there dev cycle's are in the weeks. So every few weeks, you need to revisit old models to make sure they work, or have a bunch of customers angry at YOU, and not the developer of Xplane. Everyone I have ever spoken with about developing for Xplanes laugh it off, or turn faint at the thought. Its just not 3rd party friendly like FSX. I really hope Flight is 3rd party friendly, and considering they want an online store, they NEED to be. Whats the use of having your own store if you have nothing to put on the shelf to sell?

[mgh 89]

Before we get too deep into a discussion of the relative merits of X-Plane's and FS's areodynamics let me quote from the X-Plane website. http://www.x-plane.c...de_X-Plane.html"Downwash is found by looking at the aspect ratio, taper ratio, and sweep of the wing, and the horizontal and vertical distance of the "washed surface" (normally the horizontal stabilizer) from the "washing surface" (normally the wing), and then going to an empirical look-up table to get the degrees of downwash generated per coefficient of lift." (My emphasis)So it's not all calculated on the fly.I'm pretty sure I understand how FS deals with flight dynamics. I'm not at all sure I know how X-Plane does it. Can anyone provide links that explain X-Plane - going beyond the general words in the previous link?

[Attila 2]

If the methods used to calculate flight dynamics in XP9 were any good, the default planes would not have a roll rate like an F16, among other things. It makes no difference how you get to an incomplete flight model if you have to manually tweak it just the same.As for the constant updates and user interface, I think this all comes down to the fact that XP has no professional programming roots. It is clear that there are no such things as functional specifications before development starts and no attempt is made to be backward compatible with previous versions.XP seems to be going down the path that all other games are taking. Putting more and more eye candy in, but not paying attention to many other things that are more important.The problem is that we can't blame them as people buy games based on screenshots, not game play.

[Chock 17,769]

XP seems to be going down the path that all other games are taking. Putting more and more eye candy in, but not paying attention to many other things that are more important.

Couldn't agree more. Many people are going into raptures about the way Flight looks based on the paltry number of screenshots that have been shown. I couldn't give a toss about how it looks, what does it fly like? The name of the product is 'Flight', not 'Eye Candy'.Al

[orchestra_nl 923]

Couldn't agree more. Many people are going into raptures about the way Flight looks based on the paltry number of screenshots that have been shown. I couldn't give a toss about how it looks, what does it fly like? The name of the product is 'Flight', not 'Eye Candy'.

I think "eye candy" is an important part of the sim. The popularity of scenery add-ons show that many agree. Off course realistic (or at least believable) flight characteristics and simulation of aircraft systems is equally important. It all depends on what kind of flightsimmer one is.

[TedG 1]

In reality the experience provided by XP 9.6.7 (or higher...latest 9.7 is just a couple of minor tweaks) is quite enjoyable and plenty of quality payware options as well.As far as speculating about XP10/MS Flight....as far as I am concerned they are vaporware until they go retail and real comparisons can be made.The bonus for every sim enthusiast is-obviously-choice....errrr....unless you happen to be on a Mac/Linux OS where XP afford everyone the opportunity to enjoy the hobby-not just MS WIN users :(.And by the way-as far as dev houses "running away from XP"....you will note that dev houses ranging from the large (Aerosoft) to the smaller (Carenado) and even one man bands (Air Hauler) have made successful entry to the XP market. Not to mention the growing number of quality independent developers native to XP.Just sayin!

[Chock 17,769]

I think "eye candy" is an important part of the sim. The popularity of scenery add-ons show that many agree. Off course realistic (or at least believable) flight characteristics and simulation of aircraft systems is equally important. It all depends on what kind of flightsimmer one is.

Oh I'm not disputing that, otherwise I would never have bought any sceneries for FS. But when MS releases screenshots, but nothing about improvements to how it actually simulates flight, which when all is said and done is the whole point of a flight simulator, then it doesn't exactly fill me with optimism in regard to where their priorities lie.If one only cares about how a flight sim looks and not what it flies like, then there is no need to wait for Flight to come out, because you can get all the eye candy you need in other games that concentrate more on looks than fidelity. Frankly, I'd put up with Flight Sim looking like FS98 if it actually simulated flight and air mass modeling better.Al

[PingPong 60]

I think it bears stating that the view out the cockpit is also an important part of flight "simulation", at least as a part of "suspension of disbelief". My FS flights are usually GA/IFR operations to echo what I do in real life, and X-plane's empty desert airports make it hard for me to enjoy the sim(thankfully they are addressing this).Besides as all these discussions end up leading to, there's no "correct" way to flight sim, it all different strokes for different folks.

[Chock 17,769]

That's certainly true, although one would certainly hope that the advances possible in computing would make the evolutionary process that MS Flight Sims have been through over the years involve more than simply visuals in their forthcoming stab at it. I'll be happy to see it looking more realistic of course, but the opportunity is there for MS to make it feel more realistic too.Al

[Guest ShinyJetSyndrome]

If the methods used to calculate flight dynamics in XP9 were any good, the default planes would not have a roll rate like an F16, among other things. It makes no difference how you get to an incomplete flight model if you have to manually tweak it just the same.

That brings up a debate about how to accurately model control forces when 98%+ of your flight sim pilots aren't going to have any sort of force feedback controller.Let me tell you that a lot of aircraft are capable of relatively fast roll rates (more than you would expect from FS) if you go full deflection at a cruise airspeed. The thing is aerodynamic load is going to keep you from doing that in real life but with your PC yoke or joystick there's nothing stopping you from going full deflection. Speaking for the CH Products yoke, the travel between neutral and full deflection for the ailerons is around half the distance compared to the large yoke in the later model C172's. So you can expect to get much more of a response out of a PC yoke than say in real life.That said, I've got around 50ish hours in Frasca's C172SP, Seminole and CRJ-200 Flight Training Devices and their flight dynamics/control forces aren't all that great compared to real thing either. (And both FSX and XP9 easily outdo their graphics engine ) Only differences are they cost thousands of dollars more than your PC and you can log time in them. (Depending on FAA certification of course.)

[n4gix 4,947]

Again I haven’t tried Xplane, but because building an accurate geometric model is more intuitive, I think the Xplane process will make the average flight model better.

Danny, unless something's changed, there are actually two separate models involved. One from which the "flight dynamics" are derived, and the other (optional) model which is strictly visual...