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Dc6's flight model?

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Hearing some talk through different streams and forums that the dc6 overrides x-plane's flight model and utilizes it's own, based on fsx/p3d engine to make a future port easy.

Is this really the case? Did i just buy another train simulation? :-(

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I don't think that's possible, the way flight modelling works in the two sims is completely different...

 

Anyway, whether it was or not I don't know, but it flies like a dream!

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Hearing some talk through different streams and forums that the dc6 overrides x-plane's flight model and utilizes it's own, based on fsx/p3d engine to make a future port easy.

Is this really the case? Did i just buy another train simulation? :-(

There is a massive misconception among some XP fans about FSX being very rigid due to using look up tables. The implication being the tables make the sim run on pre programmed "rails". Nothing could be further from the truth. FSX look up tables calculate aerodynamic coefficients and derivatives, as functions of AOA, Mach, beta, etc, for the whole aircraft. The flight model uses those to calculate forces and moments which drive the equations of motion. It is a dynamic flight model. The feeling it flies on rails may be based on how the default aircraft fly. It's perfectly possible to create a very lively, fluid, flight model using the FSX air file.

 

XP must also use look up tables to compute lift drag and pitch coefficients for each aerofoil element. The difference is only that these are computed at a lower element level in XP then integrated to the whole aircraft.

 

The idea that PMDG bypassed XP flight model makes no sense whatsoever. Sounds like a lot of extra work to me and a waste of the potential the XPlane system offers.

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Hearing some talk through different streams and forums that the dc6 overrides x-plane's flight model and utilizes it's own, based on fsx/p3d engine to make a future port easy.

Is this really the case? Did i just buy another train simulation? :-(

 

Not possible.

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Hearing some talk through different streams and forums that the dc6 overrides x-plane's flight model and utilizes it's own, based on fsx/p3d engine to make a future port easy.

Is this really the case? Did i just buy another train simulation? :-(

Utter rubbish.

 

The FSX flight model is very simple. It is far too stable, and good luck doing anything outside of normal flying without the flight model going crazy (falling upwards? Really?).

 

Two seconds flying the DC-6 will tell you it's using the XP flight model. Sure, it too has its limits, but is far more advanced than anything FSX provides.

 

Rob Smith.

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Utter rubbish.

 

The FSX flight model is very simple. It is far too stable, and good luck doing anything outside of normal flying without the flight model going crazy (falling upwards? Really?).

 

Two seconds flying the DC-6 will tell you it's using the XP flight model. Sure, it too has its limits, but is far more advanced than anything FSX provides.

 

Rob Smith.

It's very easy to make X-Plane, as well as FSX flight models go crazy.  We've all seen some pretty silly looking videos over the years.  How about the X-Plane Cessna 172 hauling a 747 across the sky, hanging vertically on a rope?   As to the FSX flight model, it can do plenty, when it comes to flying outside normal A to B flight.  Over the years, developers for different versions of MSFS, have gotten far past the default limitations. Same for X-Plane.  A few years back, X-Plane would sometimes go nuts, when rolling inverted. 

 

As to myself, after owning all versions of MSFS since the beginning, as well as XP 8,9, and 10, and using all of X-Planes demos since somewhere around 1994..........................I'm finally really enjoying X-Plane 10.  The very annoying left roll, has finally "left" so to speak.  It's graphic portrayal of mountains, deserts, and night lighting is exceptional. Some new small GA models for X-Plane, such as a Cessna 172 & Piper Cherokee are actually "stable" now!  Just like the real ones. Imagine that!  I flew a lot of real life Cessnas & Pipers.  Then went on to higher performance experimental class, as well as the Pitts, Marchetti SF260, Stearman, and lot's of others.  I built & owned an semi aerobatic RV with C/S prop.  In all that time, I was never wowed with X-Plane's flight dynamics, no matter what some people claimed. I now feel, that X-Plane is there.  With a high power system that runs both X-Plane & FSX fluidly with high frame rates, there actually isn't much difference in the upper end flight models between the two sims.  At the moment, I'm favoring X-Plane for it's mountain topography.  And no one can beat those night lights!

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It's very easy to make X-Plane, as well as FSX flight models go crazy.  We've all seen some pretty silly looking videos over the years.  How about the X-Plane Cessna 172 hauling a 747 across the sky, hanging vertically on a rope?   As to the FSX flight model, it can do plenty, when it comes to flying outside normal A to B flight.  Over the years, developers for different versions of MSFS, have gotten far past the default limitations. Same for X-Plane.  A few years back, X-Plane would sometimes go nuts, when rolling inverted. 

 

As to myself, after owning all versions of MSFS since the beginning, as well as XP 8,9, and 10, and using all of X-Planes demos since somewhere around 1994..........................I'm finally really enjoying X-Plane 10.  The very annoying left roll, has finally "left" so to speak.  It's graphic portrayal of mountains, deserts, and night lighting is exceptional. Some new small GA models for X-Plane, such as a Cessna 172 & Piper Cherokee are actually "stable" now!  Just like the real ones. Imagine that!  I flew a lot of real life Cessnas & Pipers.  Then went on to higher performance experimental class, as well as the Pitts, Marchetti SF260, Stearman, and lot's of others.  I built & owned an semi aerobatic RV with C/S prop.  In all that time, I was never wowed with X-Plane's flight dynamics, no matter what some people claimed. I now feel, that X-Plane is there.  With a high power system that runs both X-Plane & FSX fluidly with high frame rates, there actually isn't much difference in the upper end flight models between the two sims.  At the moment, I'm favoring X-Plane for it's mountain topography.  And no one can beat those night lights!

Spot on!

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It's very easy to make X-Plane, as well as FSX flight models go crazy.  We've all seen some pretty silly looking videos over the years.  How about the X-Plane Cessna 172 hauling a 747 across the sky, hanging vertically on a rope?   As to the FSX flight model, it can do plenty, when it comes to flying outside normal A to B flight.  Over the years, developers for different versions of MSFS, have gotten far past the default limitations. Same for X-Plane.  A few years back, X-Plane would sometimes go nuts, when rolling inverted. 

 

As to myself, after owning all versions of MSFS since the beginning, as well as XP 8,9, and 10, and using all of X-Planes demos since somewhere around 1994..........................I'm finally really enjoying X-Plane 10.  The very annoying left roll, has finally "left" so to speak.  It's graphic portrayal of mountains, deserts, and night lighting is exceptional. Some new small GA models for X-Plane, such as a Cessna 172 & Piper Cherokee are actually "stable" now!  Just like the real ones. Imagine that!  I flew a lot of real life Cessnas & Pipers.  Then went on to higher performance experimental class, as well as the Pitts, Marchetti SF260, Stearman, and lot's of others.  I built & owned an semi aerobatic RV with C/S prop.  In all that time, I was never wowed with X-Plane's flight dynamics, no matter what some people claimed. I now feel, that X-Plane is there.  With a high power system that runs both X-Plane & FSX fluidly with high frame rates, there actually isn't much difference in the upper end flight models between the two sims.  At the moment, I'm favoring X-Plane for it's mountain topography.  And no one can beat those night lights!

Aircraft in those scenarios aren't really being flown using the flight model and there is some "simisms" going on as well that just aren't taken into account when towing an aircraft. Not a good example of an absurd thing that happens with the XP flight model.

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Not possible.

Curious, is there a technical reason this isn't possible?  Does X-Plane not allow it in some way?

 

I like many own all the flight sims, rarely fly X-Plane and love P3D, and I only see external flight models as a good thing to overcome either sims shortcomings if the developer sees fit for their use case.

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Anything is possible with enough time, resources and money but why would their very first X-plane project then discard everything XP has to offer...makes zero sense.

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Anything is possible with enough time, resources and money but why would their very first X-plane project then discard everything XP has to offer...makes zero sense.

Anything is possible with enough time, resources and money but why would their very first X-plane project then discard everything XP has to offer...makes zero sense.

Precisely. Any changes that have to be made to the flight model are done differently than they would in P3D. Where's @Morten when you need him?

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"  With a high power system that runs both X-Plane & FSX fluidly with high frame rates, there actually isn't much difference in the upper end flight models between the two sims. "

 

As a r/w pilot and also having owned all versions of X-plane and FSX, I couldn't agree more with LAdamson on this.  In fact, IMHO, some of the earlier version s of X-plane (that also had the "blade element" model) actually had pretty unrealistic flight models - remember when the planes felt like they were made of paper mache with no mass or inertia?  Admittedly, there were few payware addons then for XP then.

But now, the best flight models from both sims feel equally good to me - just MHO....  :-)

 

Cheers

JJB

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Where's @Morten when you need him?

 

Morten could justify the fact, that putting in a plane's dimensions, into Plane Maker wasn't a surefire method of getting an accurate flight model. Basic ballpark at best. He spent a lot of time, improving the Piper  Archer flight characteristics over the years.  Made for interesting reading, back then. 

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Gents,

 

This rumor is coming about because someone went scouring through our aircraft's folder and found the PFPX profile (that was made as a freebie for people, mind you), apparently missed the first line that notes it as a PFPX file, and went running off with this idea that it was proof that we used an external FSX mod.

 

...that's also not mentioning that the file is located in the 'documentation' folder.

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Some people don't like change and hold on to dead things. IE FSX. They are convinced FSX is superior to XP yet have never really given XP a fair go and will try and discredit anything to do with XP no matter how great it is.

 

That's just what I see!

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Some people don't like change and hold on to dead things. IE FSX. They are convinced FSX is superior to XP yet have never really given XP a fair go and will try and discredit anything to do with XP no matter how great it is.

 

Not sure I follow. People are trying to discredit our X-Plane offering by claiming it's using an FSX external flight model (by using our PFPX profile as evidence). This sentiment isn't coming from users of FSX...

 

No need to lay down fuel for the platform flame war, either.

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Simple question:

 

X-Plane uses blade element theory for physics calculations.

 

What does FSX use, precisely?

 

The sim1.dll dates back to FS3.0 (and perhaps as far back as FS1.0). It is what drives the flight models right up to FSX today.

 

All this ignores something extremely important:

 

FSX flight model runs at a paltry 18 Hz! It is also incredibly low resolution on its data.

 

A good flight model needs to run in excess of 120 Hz to have any chance of behaving realistically.

 

Rob Smith.

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Oh come on, neither sim is entirely realistic when pushed outside the limits.  Even superb P3D aircraft like the Majestic Q400 can keep climbing to altitudes seen only to the SR-71, on X-Plane the default 747 is capable of barrel rolls, and immelman loops like an Extra 300L. 

 

So i don't think you can say one engine is better than another, it's the skill of the people developing for it.

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Oh come on, neither sim is entirely realistic when pushed outside the limits.  Even superb P3D aircraft like the Majestic Q400 can keep climbing to altitudes seen only to the SR-71, on X-Plane the default 747 is capable of barrel rolls, and immelman loops like an Extra 300L. 

 

So i don't think you can say one engine is better than another, it's the skill of the people developing for it.

 

Come now, comparing the Majestic Q400 to the default 747? Play fair haha.

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Come now, comparing the Majestic Q400 to the default 747? Play fair haha.

 

Without dwelling on this, i have no horse in this race, i prefer DCS to either P3D or X-Plane.  I think you missed my point, i was stating that the underlying engine is not indicative of the quality of the add on aircraft; it is entirely down to the skill of the person developing for them.  

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Without dwelling on this, i have no horse in this race, i prefer DCS to either P3D or X-Plane.  I think you missed my point, i was stating that the underlying engine is not indicative of the quality of the add on aircraft; it is entirely down to the skill of the person developing for them.  

 

I understood it. So you're calling Majestic unskilled? ;)

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I understood it. So you're calling Majestic unskilled? ;)

 

Sigh...not at all, quite the opposite actually.  For the 3rd time, I was (apparently failing) to make two points:

 

1. When pushed into extremes neither engine behaves particularly well.

2. The underlying engine does not determine the quality of the flight model of all aircraft running on it.  Compare the defaults to amazing aircraft like the IXEG 737 and (i dare say) the DC6 on X-Plane, or the 737NGX, A2A C182 on FSX/P3D.

 

The person above me in the forum, Rob, indicated that X-Plane uses Blade Element theory, like it was some kind of magic engine that turns all aircraft into amazing representations of the real world ones, i was attempting to point out that isn't the case.  Both engines can produce excellent results, depending on the people developing for them.

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Sigh...not at all, quite the opposite actually.  For the 3rd time, I was (apparently failing) to make two points:

 

1. When pushed into extremes neither engine behaves particularly well.

2. The underlying engine does not determine the quality of the flight model of all aircraft running on it.  Compare the defaults to amazing aircraft like the IXEG 737 and (i dare say) the DC6 on X-Plane, or the 737NGX, A2A C182 on FSX/P3D.

 

The person above me in the forum, Rob, indicated that X-Plane uses Blade Element theory, like it was some kind of magic engine that turns all aircraft into amazing representations of the real world ones, i was attempting to point out that isn't the case.  Both engines can produce excellent results, depending on the people developing for them.

 

Looks like you missed the ;) haha.

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The major advantage is that it can correctly model individual airfoils (FSX can't - its internal representation is a rhombus!), and all the subtle details that make the difference between a Beech 36 and an Extra.

 

FSX uses simple effects like control authority to simulate that difference, but if you ever edited the Cessna to make the engine rediculously powerful, it is no different to the Extra.

 

Note that I'm talking normal handling here, not extreme maneuvers.

 

Rob Smith.

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IMHO ( really humble these days... ) I feel that the potential in X-Plane's FDM is bigger than in MSFS core FDM, still used in DTG Flight School, Prepar3d and partially in MS FLIGHT, although MS FLIGHT goes a bit further in some aspects...

 

There isn't for instance any fair comparison between rotary wing flight dynamics in MSFS vs X-plane 10, and DODOSIM doesn't count because it uses, just like the Q-400, and external fdm!

 

This being said, it doesn't certainly put X-plane 10 in the winners podium because a developer wanting to get out of it the performance required to build an aircraft model as close as possible to real figures will have to strive to get there, and be very "creative" in order to find viable ways to bypass the simpistic "plausibility" assumptions made by X-planes flight dynamics in some areas.

 

Systems wise it's pretty much the same I guess. Although X-plane offers some more elaborate control, thrust, and a few more systems by simply using it's standard Plane-Maker tool, I am sure just like in the most sophisticated add-ons for FSX a lot of code must be written to be able to model details.

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