Technical questions about the flight model in FS

[Daube]

Hi all,

I just hope Phyl Talyor or any FS guru comes across this subject.
This subject is NOT about bashing, I'm just looking for simple answers concerning certains facts around the FS flight model

- The rocket engine: It is missing in FS, it never was there if I'm not mistaken. However, a simple way to reproduce it would be an engine with no lag and no flameout altitude, so I was wondering why it was never implemented in FSX ? (especially considering the fact that space flight is now technically possible)  :-?

- The speed limit: I would like to know why a maximum speed (2000 knots or something ?) exist in FS ? The max altitude could be removed (well, updated, let's say), so why not the speed ?

- The space flight: The orientation of the aircraft in space could be emulated with slewing functionnalities, so why isn't there a system like that in FS ?

- Orbit: Ok, an aircraft is not controllable in space in FS for now (until someones creates a module for that), but I would just like to know, if this speed limit would not exist, would an orbit flight be possible ? I mean, if I would place an aircraft at a certain altitude (200 kms for example) and at the correct speed (something around 8 km/sec if I remember well from MS Space sim), would it stay in orbit with the current physic engine of FS ?

Quite a lot of questions actually
I know some of the limits of the FS engine, but I do not know why some of them exists, that's why I ask.
Hoping that someone can answer.

PS: We're talking about FSX. Please avoid answers like "FS is flight sim, no space sim, use Orbiter instead blabla"

[EchoLdrWolf]

As for the physiscs, you must remember that many world generators don't acctually have a "gravity" programmed to keep you on the ground. Most of the time, you are a stationary object in which the environment of the game moves around using hundrens of formulas to position itself around you in reaction to what control inputs you make. You would have to either take hours of time to enterpret the game files or find out from a designer of the Flight Sim engine to see how it works, if it's programmed with artificial "gravity" and physics, then you should be able to tweak everything to attain orbital and space flight. You could edit a modual for the Earth's rotation which, coupled with gravity, should allow an altitute which you could orbit the world.

[Daube]

As for the physiscs, you must remember that many world generators don't acctually have a "gravity" programmed to keep you on the ground. Most of the time, you are a stationary object in which the environment of the game moves around using hundrens of formulas to position itself around you in reaction to what control inputs you make. You would have to either take hours of time to enterpret the game files or find out from a designer of the Flight Sim engine to see how it works, if it's programmed with artificial "gravity" and physics, then you should be able to tweak everything to attain orbital and space flight. You could edit a modual for the Earth's rotation which, coupled with gravity, should allow an altitute which you could orbit the world.

Yes, I have programmed a little sim (never had time to finish unfortunately...) which was using vectors etc... and aritificial gravity like you said. It simply was the easiest solution to implement, and I could really quickly simulate planes and helos moving (not very realistic flight models of course, but general flying laws were there).

But this is not the question here. I know that FS does not use the same model, at least not exactely, and I understood why. My questions above are just to satisfy my curiosity.

One question I could add is: "what do you plan for the physics model in the next FS ?", but I'm quite sure they would not even be able to answer this yet, this the developpment didn't even start :/

[EchoLdrWolf]

Well, actually, The new FS is in developement. Should come out around 2010. "FSX: Adrenaline"

[Daube]

Well, actually, The new FS is in developement. Should come out around 2010. "FSX: Adrenaline"

Errr.... FSX Adrenaline was the old name planned for Acceleration...
And ACES is currently working on Train Sim 2 if I'm not mistaken.

[reider]

Sure they said they were working on both after Christmas just gone......

Reider

[Felix/FFDS]

From what I heard them say ( as of Nov.2007), the next entertainment release of the core platform is Train Sim, AFTER which work on FS11 will pick up.

*I* don't expect any new version until mid-late 2009.

--------------------------------------------

Daube's questions are valid, but they have to be put in a certain perspective.

This is an entertainment product, and with a particular  focus - the civilian flying experience.  With that in mind, simulating the rocket engine and space flight is, in my oipinion, "outside"  the target focus of the product.  It's not that it cannot be simulated in some manner, but as it is not part of the overall focus of the product, I would not expend resources to simulate a completely different environment.  As for speed, again - if you're simulating civilian flight, devloping the complex flight dynamics of ultra high speed is "outside"  the scope.

My own speculation is that future versions of the entertainment sim will still be focused in an atomspheric model.  The core platform is shared by at least three "products"  (EXP, FS and TrainSim) and the target markets for each appear to be atmospheric/ground.

That's my tuppence worth.

[Daube]

Felix, I'm not so sure that FS was really "aimed" at civil flight only.
What we could fly until now were only civil planes, if we consider the default aircrafts.... but if you consider the addons, since FS4 a huge part of them are aimed at military stuff.

From a simulation point of view, there's just no difference at all between simulating a civil aircraft flying or a military one, the same rules apply to both, there's no exception.

Additionnaly, if we looks at FSX, we can now access space, and with Acceleration, we finally get the fisrt default military plane, with military carrier operations included.

If you want to simulate flight, you have to simulate all the aspects of the flight, not just the one of the prop plane flying level at 60 knots....

[T.Burgess]

most prop planes fly at least 120 kts in cruise flight  ::)

anyways, I do agree, however I always thought the biggest part of sim flying was flying commercial airliners, and ACES have included support for those for a long time.

I do think military deserves attention, however I love GA, and since most people love high and fast on here, it doesn't really get as much attention as it deserves. I thought it was a great idea to include all those GA planes, but next time maybe a few fighters as well.

[Felix/FFDS]

Felix, I'm not so sure that FS was really "aimed" at civil flight only.
What we could fly until now were only civil planes, if we consider the default aircrafts.... but if you consider the addons, since FS4 a huge part of them are aimed at military stuff.

From a simulation point of view, there's just no difference at all between simulating a civil aircraft flying or a military one, the same rules apply to both, there's no exception.

Additionnaly, if we looks at FSX, we can now access space, and with Acceleration, we finally get the fisrt default military plane, with military carrier operations included.

If you want to simulate flight, you have to simulate all the aspects of the flight, not just the one of the prop plane flying level at 60 knots....

Let me clarify.  Flight Simulator, since its inception, has been a "civilian"  entertainment product, in that no "real"  combat has been deliberately programmed.  The "military"  simulators have been the Combat Flight Simulator versions.  Inevitably, one version complements the other, which is why the CFS series have been, in effect, "FS-n"  variants.   In fact, I remember FS2 had a rudimentary combat part in which one could fly a Sopwith Camel against Fokker DR.1s.

Of course flying "military"  planes has been a part of Flight Simulator from Day 1.  

I am not saying that we will not see Space Flight and higher speeds in FLight Simulator.   I think that base for them are either already there in FS, or are being planned as part of the core platform that is being shared between the ACES products.

My feeling is that *right now*  the emphasis is on atmospheric flight, and non-combat missions/adventures.

[Daube]

Felix, I'm not so sure that FS was really "aimed" at civil flight only.
What we could fly until now were only civil planes, if we consider the default aircrafts.... but if you consider the addons, since FS4 a huge part of them are aimed at military stuff.

From a simulation point of view, there's just no difference at all between simulating a civil aircraft flying or a military one, the same rules apply to both, there's no exception.

Additionnaly, if we looks at FSX, we can now access space, and with Acceleration, we finally get the fisrt default military plane, with military carrier operations included.

If you want to simulate flight, you have to simulate all the aspects of the flight, not just the one of the prop plane flying level at 60 knots....

Let me clarify.