XP is just different and for me as a designer and pilot XPs plane design is simply much more limited than FSX.If we could agree that XP is just 'different' I wouldn't even post here!But with Austins bragging and e.g. Mortens statements I think that 'armchair' pilots do get a wrong impression about XP and that it is superior to FSX and this is simply not the case.

BTW--- I haven't tried your models yet. I hear they're good designs. That X-Plane is different.............is exactly how I feel. I believe I've tried to convey that here. When speaking of armchair pilots, I was not speaking of Goran. L.Adamson

I beg to differ here... having spent a considerable amount of my life flying one for a Southeast USA based Cargo Operator I can say that Tom's MU2 is pretty darn real. Most folks who initially complained about the flight characteristics of his MU2 either didn't read the documentation or incorrectly thought all planes flew like a Cessna 172...

Yes, be he said Beta.

Yes, be he said Beta.

But BETA and "horrible problems" aside, Tom hit the nail on the head and modeled its unique flight characteristics to a T...

@Morten >Wow - EXACTLY LIKE REAL - Thats both arrogance and serious ignorance, sorry Bernt, wake up and smell the coffee.Is this what you tell your customers. I don't know what kind of serious problem you have with FSX and its capabilities.If the simulated plane has the same pitch rate, roll/yaw instability during the stall break and enters the spin exactly like its real world counterpart....what else would you call it if not 'exactly like the real one'?Accept the fact that this is apparently only possible in FSX.It was you who mentioned that XP sucks... @ Jacoba With the Mu-2 beta you had to apply full aileron after lift off during the initial climb just to keep the wings level and I severly doubt that the real one would have been certified with that 'characteristic'

With the Mu-2 beta you had to apply full aileron after lift off during the initial climb just to keep the wings level and I severly doubt that the real one would have been certified with that 'characteristic'

No your right, but it seems to me the issue with Tom's MU2 was a tweaking issue with the add on itself and not XP, evidence to this is that it works fine today and flies remarkably like the real one does.

Goran, I was working with Morten when he was developing the 757 for x-plane and he is a very knowledgeable guy and it was a great pleasure working with him, no doubt about that.And you are correct, he for sure wasn't arrogant at that time. ( BTW just to make sure, it was Morton who said that XP sucks at stalls and spins!)

He might be of the opinion that X Plane sucks at stalls and spins, but, I have to say, I nailed the stall properties in my Duchess pretty good. Admittedly, I haven't tried deep spins though. Doesn't mean he doesn't think the stall properties in FSX are worse.

I don't know what has happened and I don't care at all who is using which simulator. I used to design planes for x-plane from v.HSR to v9 and for MSFS from fs9 to fsx and I simply found XP to be too limited.The basic idea of simulating actual airflow is nice but computing power is way too low and the blade element theory too primitive for precise results. Even Boeings super computers predicted the airflow, wing bending moment etc for the brand new 747-8 wrong so why should a cheap desktop sim be any better?If you build a plane in XP which looks like the real world counterpart it will fly approximately similar and it's a nice basic design tool.So far I haven't flown a convincing XP designed plane.It was frustrating during the XP MD-80 development and even more with the Hansajet with the forward swept wing to run into unexpected XP limitations and that's why I always gave up because getting stuck after investing a lot of work isn't fun.

Ok, fair enough. If that is your opinion, that's fine. But, how limited is FSX's flight model? No one here has once spoken out against the FSX flight model. About the only mention I have seen of it is PMDG's statement as quoted by Morten.I have delved into Planemaker quite extensively over the last year and there is so much that the vast majority of developers DON'T know about x plane. I've had many "ahhh, that's how I can do it!" moments. The way you, and many FSX supporters feel about FSX is exactly the same how many X Plane supporters feel about X Plane. This must be accepted by both groups as no one is willing to budge based on what each group knows.

The most advanced XP design I flew was the Mu-2 beta which had horrible problems in simulating the roll spoilers.In FSX you can build every feature and behaviour you want into the flight model but it's way more complex than in XP.Actio = Reactio and hence if you invest a lot of time you get very convincing flight models in FSX.

I do know a lot about FSX development. I moderated a forum for an FS9/FSX developer. I'm in touch with another FSX developer who is making a very important add on yet to be released. I know about FSX's mdl. I've had a look at the sdk. It simply does not ask for what X Plane asks for. In particular, airfoil properties, co-efficient of lift, co-efficient of drag (for both the fuselage AND the engine nacelles) propeller pitch and chord, etc...

Both, PMDG and Realair aren't top notch concerning flight dynamics. PMDG never was and Realair never improved after their SF260. I'm into real flying, aerodynamics and flightsims since at more than 30 years now and I don't understand why Morton and others are constantly trying to claim that XPs flight modeling is superior to FSX. (XPs failure model is really superb and well ahead of FSX)

Because we BELIEVE it is. I've spent several hours a day, 4 days a week, for about a year, studying Planemaker and x planes flight model. Sometimes with the help of aerodynamics reference material. I haven't seen FSX's SDK have the information that is contained in Planemaker or Airfoil maker. I can say that FSX's SDK is highly customizable. But instead of forcing the aircraft to do what I want it to do (like you would have to in FSX), I would rather let the platform decide based on the real world variables I give it. If something goes wrong, I try to figure out what variable is inconsistent and fix it. If I can't fix it that way, I then manually force it, but only as a last resort. I have only had to do that once with the Duchess. Albeit a very small adjustment to get the airspeeds accurate in all areas of the flight envelope.

XP is just different and for me as a designer and pilot XPs plane design is simply much more limited than FSX. If we could agree that XP is just 'different' I wouldn't even post here!But with Austins bragging and e.g. Mortens statements I think that 'armchair' pilots do get a wrong impression about XP and that it is superior to FSX and this is simply not the case.

Of course they are different. I have been saying that all along. But the big difference is, you think FSX is better. Morten and I think otherwise. We respect your decision. I ask that you respect ours. I don't know how far you got into Planemaker. It seems MANY x plane developers think they know everything about Planemaker. They are like poker players. They all think they're good. But only a few actually are. I've been developing for x plane in a full time capacity for over 2 years...and I am STILL learning new things about Planemaker.

@Morten >Wow - EXACTLY LIKE REAL - Thats both arrogance and serious ignorance, sorry Bernt, wake up and smell the coffee.Is this what you tell your customers. I don't know what kind of serious problem you have with FSX and its capabilities.

This is EXACTLY what we ask you, Jim, Larry and Tierborn when you say things against X Plane. Like I said, I know FSX's SDK. It is MUCH easier to make add ons for FSX than it is for X Plane. The market is richer for FSX. Yet I consciously chose to develop for X Plane because, IN MY OPINION, I believe it to be better.

This is EXACTLY what we ask you, Jim, Larry and Tierborn when you say things against X Plane. Like I said, I know FSX's SDK. It is MUCH easier to make add ons for FSX than it is for X Plane. The market is richer for FSX. Yet I consciously chose to develop for X Plane because, IN MY OPINION, I believe it to be better.

I don't know the techniques for FSX. I don't program. I don't care to program..................but I know it's a b-i-t-c-h of hacking backward engineering to get it correct. And that's because I've worked with a number of MSFS developers over the years. The good MSFS designers have spent years to become voodoo and black magic experts. If you think it's a matter of filling in a few tables here and there.... then you've got it wrong. L.Adamson edit.........thought the first word was I to start with

If you think it's a matter of filling in a few tables here and there.... then you've got it wrong.

And vice versa.

And vice versa.

And that's also what I hear.. L.Adamson

The good MSFS designers have spent years to become voodoo and black magic experts.

That's exactly the point. If one needs years to become really proficient in FDs design I expect from the sim first class results in the end and not a stall/spin model that sucks. Since XP1 constantly basic problems with XP appear and many times it's not possible for the designer to correct them but to simply wait for Austin to release a new version which corrects this error. E.g. AFAIR that was exactly the problem with the Mu-2.At one point Austin even deleted the flap design table (very similar to the airfoil maker) in planemaker for whatever reason.To convince Austin to add ground effect simulation took years and in FSX I can even tune ground effect.Sometimes the basic changes are so big that e.g. a complete redesign of the engine model is neccessary because basic flaws are being discovered all the time.

I know about FSX's mdl. I've had a look at the sdk. It simply does not ask for what X Plane asks for. In particular, airfoil properties, co-efficient of lift, co-efficient of drag (for both the fuselage AND the engine nacelles) propeller pitch and chord, etc....

We agreed that it takes years to find out how to design good flight dynamics and now you say you took a look at the SDK.What did you expect to find after just 'taking a look' ?FYI the mdl file contains absolutely nothing about the flight model in FSX. You are looking at the wrong place.The SDK also contains almost no information about air file design, again that's not the place to get any serious info about it.If FSX wouldn't look for C_L or prop pitch etc... how would it be possible to design a plane ???E.g. there are 2 separate prop entries in the airfile, each with 6 tables by default (you can add of course tables if you deem it neccessary) not counting the additional tuning options in the cfg file. You never designed flight dynamics for FSX and you don't even remotely know its capabilities.Nevertheless you claim that XP is better despite your apparently wrong and incomplete knowledge about FSX.

We agreed that it takes years to find out how to design good flight dynamics and now you say you took a look at the SDK.What did you expect to find after just 'taking a look' ?FYI the mdl file contains absolutely nothing about the flight model in FSX. You are looking at the wrong place.The SDK also contains almost no information about air file design, again that's not the place to get any serious info about it.If FSX wouldn't look for C_L or prop pitch etc... how would it be possible to design a plane ???E.g. there are 2 separate prop entries in the airfile, each with 6 tables by default (you can add of course tables if you deem it neccessary) not counting the additional tuning options in the cfg file. You never designed flight dynamics for FSX and you don't even remotely know its capabilities.Nevertheless you claim that XP is better despite your apparently wrong and incomplete knowledge about FSX.

You're absolutely right. I never designed an add on in FSX. I had a quick look (maybe 30 minutes) around the SDK. My wife always told me, "If you want to argue, argue with the wall, because I'm not listening"I'm not going to argue with you, Bernt.I have never seen anything to do with co-efficient of Lift or co-efficient of drag (for nacelles or fuselage) in the FSX SDK or AIR file or anywhere else. If you can show them to me, please, I will be more than happy to take a look. You say there are 2 separate prop entries with 6 tables by default in the FSX SDK. I forgot how many different prop designs can be used for X Plane. Let's just say you can add figures (Reynolds Numbers, Thickness Ratio at the thickest part of the airfoil, compressability effects at specific Mach numbers, intercept, slope, linear range, a setting to adjust the lift curve so it transitions into the stall, etc...) All that is just the top quarter of the airfoil maker 1st page. There are 3 more after that including a Camber design tab. Couple that with being able to import the profile of ANY airfoil that has ever been made in the history of aviation and you can easily see that FSX doesn't even stand a chance at matching what X Plane can do with airfoils. All this can be made for the wings AS WELL AS the props (since props are airfoils anyway).Please feel free to show me the equivalent in FSX. A few screenshots of Airfoil Maker. http://dl.dropbox.com/u/1192596/XP_Diagrams/21-08-2011%206-08-39%20PM.pnghttp://dl.dropbox.com/u/1192596/XP_Diagrams/21-08-2011%206-08-45%20PM.pnghttp://dl.dropbox.com/u/1192596/XP_Diagrams/21-08-2011%206-08-50%20PM.pnghttp://dl.dropbox.com/u/1192596/XP_Diagrams/21-08-2011%206-08-55%20PM.png

Delete - double post

1. I have never seen anything to do with co-efficient of Lift or co-efficient of drag (for nacelles or fuselage) in the FSX SDK or AIR file or anywhere else. 2.You say there are 2 separate prop entries with 6 tables by default in the FSX SDK. I forgot how many different prop designs can be used for X Plane. 3. Thickness Ratio at the thickest part of the airfoil, compressability effects at specific Mach numbers, intercept, slope, linear range, a setting to adjust the lift curve so it transitions into the stall, etc...) 4 Couple that with being able to import the profile of ANY airfoil that has ever been made in the history of aviation and you can easily see that FSX doesn't even stand a chance at matching what X Plane can do with airfoils.

All the points you mentioned are a proof that XP is a nice engineering type approximation....something very useful if you design a new plane or if you want to use a new concept in plane design for an initial assessment but way too primitive to exactly simulate a certain plane.If Boeing isn't able to predict and calculate the wingbending moment of their brand new 747 with the most modern high performance computers, do you really think that x-plane can seriously predict and calculate the behaviour of a complete plane? 1. I know the saying that an airplane is a lot of parts flying in very close formation and they are justed kept from desintegrating by the ability of the pilot.But in a flight sim that tries to simulate a certain plane separate a C_m for nacelles, the fuselage are useless because it's actually not a formation of parts so the only thing that counts is the total Cm. Not only that calculating separate C_m is a waste of computing power, I severly doubt that x-plane calculates the interaction between the fuselage and the nacelles. 2. No, it's not about different prop designs, it's (at least) 12 tables you use for any prop you design. 3. Why do you need the thickness ratio? Interestingly the earlier versions of x-plane didn't have that feature for a very simple reason....it's a value that's not needed. Austin implemented the feature only because x-plane used to draw a standard 15% thickness airfoil in x-plane which looked of course silly on a F-104. You have C_L C_d & C_m . Where's the need for the thickness entry except for the look of the plane?x-plane looks better than earlier with the correct thickness but it has no impact on the flight model.C_L and C_m tables are very similiar in FSX (tables 1546 and 1547). They are just not splited because they are already valid for 360deg AoA. BTW, FSX has 25! different tables to simulate compressibility for every needed control surface and their interactions. 4. Why do you want to import any airfoil in history? Does x-plane take into account if the wing is flush riveted, if there's a fuselage wing fillet? a bulge in the wing for the gear doors? There are already C_L etc...you need to adapt to a certain plane. X-planes aim is to simulate (rather coarse) the airflow which it does quite ok and that's something FSX never could do.But that's a different target than FSX has. With FSX you have to change a lot of tables in the airfile and all their interaction to be able to build a replica of a certain plane but it is possible.In x-plane you can design a plane basically without the need to know the real planes characteristics because the blade element theory is sufficient for an approximation.There's no way to get away that cheap in FSX but if you know the plane very well FSX gives you all the tools to make a very realistic real world counterpart.Well, at least 99% of the multimillion dollar flightsims also use a table based simulation. Again, x-plane is different and I really love the flow visualization and the flight path depiction but it's IMHO too primitive (not at least due to the lack of computing power) to allow an exact replica of a real plane as can be seen by the much more precise stall/spin design possible in FSX. But that's only the most visible part. Things like simulating the certain details like a tendency to dutch roll are also possible but that needs very precise tuning.

MS chose to eliminate some ground model effect around the time of 2002. It was used much more extensively in Microsoft's Combat series. X-Plane doesn't do all that well either, even though it chooses to model it. Soft & short field takeoffs in X-Plane, with yoke/stick full back, can have deplorable results as compared to the real aircraft. The X-Plane will often bury it's rear end into the pavement, swing wildly side to side, and roll over at takeoff. Of course.............this behavior can be refined by the programmer. On the other hand,,,,,,,,,,,so can the behavior of MSFS. Try the RealAir Spitfire for instance. Excellent flight dynamics on the takeoff roll...........in regard to the forces & use of rudder pedal that you'd expect. A

This is not correct LA. 1. The ground effect in MSFS is TOTALLY WRONG AN INCOMPLETE, I have proven this to you before; Below is by Michael K. Zyskowski, Microsoft. It's a few years old (FS2004)and updates have probably been made but I assume the general idea still applys. http://www.xplanefre...n/DOCS/FSGE.pdf This document it written by MSFS themselves reveals MAJOR errors and missings inthe FS ground effect model.

However, we utilize the ratio of height AGL to aircraft wing SPAN to simulatethe additional LIFT experienced in ground effect

. Ouch...!!! Thats not only way simplified, it is completely wrong! Basically they have mixed up SPAN dominated ground effect with CHORD dominatedground effect. Lift increase is a factor of CHORD above AGL, not span!It could be they had no choice since the FS wing is not devided into sections and chordslike XP is.So this means that all acft in FS with the same SPAN will experience the SAME lift increase in ground effect.A glider with the same span as a Concorde will have the same lift increase in FS.. Doh.. . Even high wing aircraft which in real usually never enters chord dominated ground effectwill get a lift increase Bummer..!Also no drag reduction or downwash pitchdown. And don't start telling me each designer can tweak it, because unless each designers builds his OWNground effect model it will always be dead wrong no matter how much you tweak! 2. I happened to be the one that documented the ground effect errors in XP to Austin a few years agoand helped him build the new one! And I can tell you we did not cut any corners. If you claim it'soff, then I want to see some DOCUMENTATION HERE NOW! You are correct in that even though ground effect is a core parameter, there are many factors on the aircraftthat impact on ground effect that the designer can tweak in XP And finally, Bernt and LA, let me once and for all make this clear: DESIGNERS IN X-PLANE ARE NOT LIMITED TO THE CONFINES OF PLANEMAKER ANYMORE. THE NEWGENERATION AIRCRAFT WE USE PLUGINS WHERE WE ALTER X-PLANES FLIGHTMODEL WHERE/IF NECESSARY. Don't know who started using the term arrogant, but just for the record, few have reported more flightmodel issuesin X-Plane over the years in public than me, and I have on several occasions told you what XP doesn't do so well.I even started XPRT - X-plane Research Team, gathered all the brightest engineers and pilots of x-plane worked got togetherto document issues of X-Plane and improve the sim. It's sole mission was to find and correct XP flightmodel issues!!! Yet, I get called arrogant by people who cant even admit ONE SINGLE error in the FS flightmodell!!!! Increddible!!! *******... guy's grow up, we are talking about simulators here made by human beings, they are BOTH FULLof errors and simplifications. Or is it just pilots that are this naive?

The ground effect in MSFS is TOTALLY WRONG AN INCOMPLETE, Also no drag reduction or downwash pitchdown.And don't start telling me each designer can tweak it, because unless each designers builds his OWNground effect model it will always be dead wrong no matter how much you tweak!

Well, every good designer alters the basic ground effect in FSX due to that fact.Of course there's a drag reduction and of course it can be different (and realistic) for every plane.May I remind you that x-plane didn't have any ground effect at all for years and once it was there it was seriously overdone and everyone had to wait until Austin deemed it appropriate to change it again.Plane maker is insufficient? A plug-in is needed? So why isn't it possible to design spins with the great plug in?I know you think that spins are not important....but it's at least as important as your quoted ground effect There are quite a few errors and shortcomings in FSX flightmodel design e.g. the lack of a dedicated drag table can make a designer pull his hair out, but many, not all of these problems can be circumnavigated by careful design. You are correct that simulators and humans are both full of errors and simplifictions and exactly that's what I don't understand.Why is the x-plane community constantly trying to convince armchair pilots that x-plane is superior while it clearly isn't.

May I remind you that x-plane didn't have any ground effect at all for years and once it was there it was seriously overdone and everyone had to wait until Austin deemed it appropriate to change it again.

So..? Want us to start debating FS4 vs XP9 He didn't have the documentation to get it right, I provided that, THEN he changed it.

Plane maker is insufficient? A plug-in is needed? So why isn't it possible to design spins with the great plug in?

It might very well be possible to improve spins with a plugin, who said it wasn't?It's even possible to modify ground effect (not that it's necessary though)

There are quite a few errors and shortcomings in FSX flightmodel design

Thanks, finally, any links on those subjects would be appreciated.

Why the x-plane community is constantly trying to convince armchair pilots that x-plane is superior which is definitely not the case.

Because it is from an engineering and aerodynamics point of view in most part of the subsonic envelope.The main reason is that FS is 1-dimensional, XP is 2-dimensional. If each individual aircraft isn't superior thats not the sims fault, but the shortcomings of the designer.