Boeing 777 Worldliner Professional vs PMDG 777

[Murmur 3,941]

In my book, as a long time real life GA flyer............I don't see any real advantages between look up tables and other methods, such as blade element. When getting out of the normal flight envelope, it's up to the programmer to supply additional information.....for the sake of realism. BTW--- this statement won't exactly apply to helicopters. I hate the buggers anyway...

 

In a post by Jcomm some days ago, there was a link to a long post of one of the developers of DCS, very interesting to read, and he precisely said that they went to a "Blade Element"-like flight model (instead of a pure "look-up tables" FM) exactly because it was the only way in which they could get that additional edge in the flight model feeling and realism.

 

Again, it's not by chance that simulators that gave top priority to flight model feeling and realism, like Condor Soaring, Silent Wings, DCS, Flight Unlimited (at the time), make all use of a "Blade Element"-like flight model. After all, a "look-up tables" FM would be far easier to code and aircrafts easier to design, so there must be a valid reason why they did not choose to do so. Maybe you don't see any real advantages and that is fine, but the developers of those flight sims do!

 

That being said, of course this does mean that any "Blade Element"-like simulator is better than a "look-up tables" one.

 

Note: Not exactly hate. I flew R/C choppers for years, and have some time in real ones, with the controls. It's just that I lived next door to a helicopter flight school, and those buggers were always hogging the pattern. And they're noisy too!

 

Everyone knows helicopters don't fly, they're just so ugly the earth repels them. :smile:

[Alec 370]

This Article, brought to this forum by Jcomm I believe, is very good to read and get to know the truth behind all the myths about FM that has been circulating the internet for years.

 

http://forum.il2sturmovik.com/topic/168-developer-diary/#entry29343

 

One thing I remember reading is that very few people has access to the Advanced Flight Model within DCS. It's like a secret they keep to the most talented groups to create approved addons, not for everyone to access and tweak. Maybe one day we will have a simulator as open as FSX and X-Plane with such advanced FM to allow people to make all the stuff they want.

[Murmur 3,941]

This Article, brought to this forum by Jcomm I believe, is very good to read and get to know the truth behind all the myths about FM that has been circulating the internet for years.

 

http://forum.il2sturmovik.com/topic/168-developer-diary/#entry29343

 

One thing I remember reading is that very few people has access to the Advanced Flight Model within DCS. It's like a secret they keep to the most talented groups to create approved addons, not for everyone to access and tweak. Maybe one day we will have a simulator as open as FSX and X-Plane with such advanced FM to allow people to make all the stuff they want.

 

That is exactly the article I was referring to, the paragraph titled "Advanced Flight Model" is very interesting to read.

 

From the descriptions given, the approach used by DCS is very similar to X-Plane. My _personal_ opinion based on that, is that the difference in complexity between the two flight models is not enormous, even if DCS could be somewhat more complex and/or accurate.

 

More importantly, I don't think DCS flight model is a "magic bullet", so even if they'd make it openly accessible, I doubt we'd see a sudden blast of new aircrafts with super-realistic flight models.

 

Infact, I'm sure that DCS developers didn't just put in the 3d shape and engine data of the P51, and voilà, out came a perfectly realistic P51 flight model. On the contrary, most certainly they had to "tweak" and tune lots of parameters to get it right, maybe not less than the best X-Plane aircraft designers do with their models.

[FlyBoyMike 38]

 

 

But unfortunately not realistic. None of the 3 flight system laws are correctly simulated.

 

Hi jcomm, sorry but do you mean the flight system laws on the FF aren't correctly simulated?

 

I personally find that when hand flying the FF it feels a bit 'unwieldy' especially during the initial climb out where it seems difficult to keep the pitch stable even with the proper trim setting (which again is calculated completely differently from the PMDG). I'll admit I'm not well versed in the scientific aspects of flight modelling particularly FBW but understand there are 3 laws that operate this in the 777 and in the FF it seems like they tried to implement some kind of FBW simulation but just doesn't 'feel' right (difficult to explain as not my background).

 

One major noticeable thing is the fixed CG on the FF so you'll always end up with the same trim settings because of this. This is probably due to the fact that you can't directly modify the weight of each section of the plane, for example passengers and cargo.

[BrianKoehler99 13]

Hi jcomm, sorry but do you mean the flight system laws on the FF aren't correctly simulated?

 

I personally find that when hand flying the FF it feels a bit 'unwieldy' especially during the initial climb out where it seems difficult to keep the pitch stable even with the proper trim setting (which again is calculated completely differently from the PMDG). I'll admit I'm not well versed in the scientific aspects of flight modelling particularly FBW but understand there are 3 laws that operate this in the 777 and in the FF it seems like they tried to implement some kind of FBW simulation but just doesn't 'feel' right (difficult to explain as not my background).

 

One major noticeable thing is the fixed CG on the FF so you'll always end up with the same trim settings because of this. This is probably due to the fact that you can't directly modify the weight of each section of the plane, for example passengers and cargo.

I think he was talking about fsx and PMDG 777  :Nerd:

[LAdamson 240]

 

I think he was talking about fsx and PMDG 777

Re-read:

But unfortunately not realistic. None of the 3 flight system laws are correctly simulated.

 

 

 

The PMDG 777 has a problem with the interpretation of some aspects of the Normal Law, but even with that small quirk, it does a tremendous job at simulating the kind of "support" the Boeing variant of the Fly-By-Wire provides, and is completely inexistant on the FF 777. Probably that is the reason why you find the FF 777 more interesting to handfly...

 

 

 

On the real thing, and in the PMDG 777, when handflying you can start a turn and it'll keep you level on the flightpath up to 30º bank.

 

It'll also keep your flightpath when changes in configuration ( flaps, gear, spoilers ) or thrust are operated.

 

JComm already replied to a question about the particular model, a few replies down from the original.

[BrianKoehler99 13]

 

Re-read:

But unfortunately not realistic. None of the 3 flight system laws are correctly simulated.

 

 

 

The PMDG 777 has a problem with the interpretation of some aspects of the Normal Law, but even with that small quirk, it does a tremendous job at simulating the kind of "support" the Boeing variant of the Fly-By-Wire provides, and is completely inexistant on the FF 777. Probably that is the reason why you find the FF 777 more interesting to handfly...

 

 

 

On the real thing, and in the PMDG 777, when handflying you can start a turn and it'll keep you level on the flightpath up to 30º bank.

 

It'll also keep your flightpath when changes in configuration ( flaps, gear, spoilers ) or thrust are operated.

 

JComm already replied to a question about the particular model, a few replies down from the original.

ok thanks

[Longranger 148]

 

PMDG can't release a plane in XPlane 10 until 10.3 version releases.  There is no official release date for 10.3 (nothing publicly stated by Laminar).  This means virtually all developers are stymied and progress is stagnant.

Either you know something about 10.30 that we don't or you are wrong. The main purpose of 10.30 has nothing to do with the flight model but with some changes for their maps and graphics systems. While their is a rumour about the 757 some developers doubt this explanation. There was obviously no problem for the Saab 340 or the update of the C208 to wait for 10.30. Furthermore you obviously know nothing about real software development. There will never be an official release date for 10.30. They will start the 10.30 beta from one day to another and they will declare a 10.30 release candidate as final after it seems to be stable.

[Robert McDonald 167]

Either you know something about 10.30 that we don't or you are wrong. The main purpose of 10.30 has nothing to do with the flight model but with some changes for their maps and graphics systems. While their is a rumour about the 757 some developers doubt this explanation. There was obviously no problem for the Saab 340 or the update of the C208 to wait for 10.30. Furthermore you obviously know nothing about real software development. There will never be an official release date for 10.30. They will start the 10.30 beta from one day to another and they will declare a 10.30 release candidate as final after it seems to be stable.

 

FlightFactor's Philipp Muenzel (who claims to be working directly with Austin Meyer and the rest of the XPlane dev team on X-Plane ITSELF, in addition to designing new aircraft,)  has stated publicly that the 757 plane his firm is building cannot be offered for sale until XPlane 10.3 is released, and that's what I 'know' and that's what I'm basing my statement on.  I would guess from his comments that there is some piece of the platform in the current version that is conflicting with his plane.  Since he is directly working on development and refinement of X-Plane 10 itself with Austin Meyer, I regard Philipp's words as having significantly greater weight and authority than those of anonymous forum posters who don't sign their real names.

 

Laminar is also threatened by an ongoing patent lawsuit, which is consuming time, energy and substantial amounts of money.  That isn't helping progress on the sim, just to state the obvious.

 

Given the fact that PMDG builds what I consider the highest quality sim planes available, if the lack of a stable version 10.3 is delaying the FlightFactor plane release, I would infer that it could impact PMDG's plans as well.  

 

You're quite right about there being nothing definite about when or even IF 10.3 will release.  Thus we have no 757 from FlightFactor, and unless I'm wrong, we aren't seeing any planes for XPlane being offered for sale by PMDG, which is EXACTLY the point I was trying to make.  

 

Most devs want the iteration they develop for to be deemed an official "stable" version, not just a 'beta', because they don't want the 'environment' (the sim) to cause unexpected support problems with their software aircraft.  It's hard enough to release a complex aircraft when you don't have to worry about bugs in the underlying sim itself.  

 

Since there is no word about 10.3 BETA -or- STABLE, nothing much appears to be happening, other than ONE new airplane and ONE existing airplane update.  I should have added the qualifying "most" in front of my statement about devs sitting on the sidelines waiting for the newer iteration.  I stand corrected, and thank you.

 

Actually, I do know something about software development, I have written programs all by myself that were commercially successful albeit not for flight simulation, one of which is still offered on CNet's Download.com.  

 

I haven't even seen a beta for 10.3, and Laminar is silent as the Mummy's tomb.  Possibly YOU know something about when the X-Plane 10.3 beta will release?  No, of course not.  If Laminar won't say it, how could anyone else know?

 

Things are so silent at LR that I for one got pretty tired of 'waiting' for the PLATFORM to mature so more AIRCRAFT could come out.

 

I acknowledge ONE new plane got released for Xplane, and another got 'an update'.  That's not exactly a gold rush of new products- I think many of the larger players are waiting for X-Plane to shake out a bit further.  I certainly can't say that EVERY dev will wait, it's all about having something to sell today, and I get that.  

 

On the other hand, a firm like PMDG has the reputation for quality products, and when they come to X-Plane, it will move the market and likely lure some of the FSX faithful to perhaps wander over for a look-see.  There are other issues with X-Plane having to do with the lack of any buildings at all default airports, blocked view to the horizon at high altitude, and missing 'four seasons' scenery that need fixing sooner rather than later, but that's a matter of personal opinion.  Even if you love Game of Thrones, you can't say "Winter is Coming" in XPlane 10.  Well, you can say it, but it's NOT coming.

 

I'm not a betting man, but I'll wager you a Grande Latte that you won't see a PMDG product for XPlane any time prior to 10.3 stable, and more likely, even later than that. BTW, I'd be THRILLED to lose that bet.

 

Cheers.

[Longranger 148]

FlightFactor's Philipp Muenzel has stated publicly that the 757 plane his firm is building cannot be released until XPlane 10.3 is released, and that's what I 'know' and that's what I'm basing my statement on.  I would guess from his comments that there is some piece of the platform in the current version that is conflicting with his plane.

 

Given the fact that PMDG builds what I consider the highest quality sim planes available, if 10.3 is delaying the FlightFactor plane release, I would infer that it could impact PMDG as well.

Oh, I see. There is you guesswork. I doubt that PMDG would really depend on the 757 and its feature set, since their planes are normally written around the FSX systems and depend on their internal management. Philip is in a different position since he is a part of Laminars crew. He probably has decided  that he don't want to write his own subsystem and instead simply wants to wait for 10.30  Instead he already writes about updates for the 777 and the CRJ 200 in X-Plane 11. A general road block for all developers , as you declare it, would have probably been taken out of the 10.30 loop and integrated into a 10.2x release.

10.30 is and will be a giant so there is no sense to rush it. Instead they are obviously still talking about a previous artwork update (10.25).

In fact after Philip talked about his decision to wait for an important chnage in 10.30 a competitor rushed to Austin to complain about an unfair advantage but Austin declared it a small feature...

Hardly a real road block for all developers, especially since many developers complained about to many and fast updates. Instead I think that after the bumpy ride to 64bit there won't be any fundamental updates for the flight model or the plug-in systems till XP 11.

[jcomm 5,939]

 

 

Hi jcomm, sorry but do you mean the flight system laws on the FF aren't correctly simulated?

 

Good observations FlyBoyMikey, and yes, I noticed that fixed CoG too, but got accustomed to it...

The 'unwieldy' feel you describe is also certainly different from what we would expect with the system used in the T7's which, quite on the contrary, tends to keep things very simple, yet still intuitive for the pilot. In the FF777 when manually fying if you let go of the yoke, the aircrat will easily drift from it's flightpath, pitch and bank and ask for permanent corrections...

 

@BrianKoheler99: Yep, in my initial post, at some point I wrote PMDG 777 where I should have written FF 777 :-/  Sorry...

[Geofa 108]

 

"Hardly a real road block for all developers, especially since many developers complained about to many and fast updates. Instead I think that after the bumpy ride to 64bit there won't be any fundamental updates for the flight model or the plug-in systems till XP 11"

 

 

..and how did that " bumpy ride" effect consumers who were told xplane 10 was a whole new animal on its release and there would be no more bumpies? Took almost 2 years for my initial purchases made on faith to be made good-or somewhat good.

 

Sad to hear there won't be any fundamental updates for the flight model-that one speaks for itself.

[Robert McDonald 167]

Nothing to add.

[Longranger 148]

"

..and how did that " bumpy ride" effect consumers who were told xplane 10 was a whole new animal on its release and there would be no more bumpies? Took almost 2 years for my initial purchases made on faith to be made good-or somewhat good.

 

Well, if you look at the chaos that Carenado had to fight against it was a very bumpy ride, with planes that were 64 bits ready and suddenly they were not... Most developers are used to write for a fixed interface set and they don't want to see that their plane was broken by the program itself. Such questions like which version of SASL does this plane use is normally something that the users shouldn't have to bother with.

 

Every big change in the flight model that is essential for one developer might break several planes by another and might push this developer to simply drop the development for X-Plane 10 altogether. You can only add features that are opaque or hidden in the normal interfaces. XP 10.10 was declared stable and they have to take care that planes that were build for this set work properly throughout X-Plane 10! There were many complaints when Laminar went around this promise with the change to 64 bit, that forced many developers to update their just XP 10 ready planes another time with this release when most customers switched to 64 bit!

Most developers expect to release their sets, add a few bug fixes and then they have to earn money. This doesn't work if they always have to return to their old planes and add another essential feature free of charge!

They can only make changes that might be helpful for new planes that trigger a new/modified feature by itself. To use this new feature they would have to publish the new switch/call in their documents. Since we haven't heard anything officially about these upcoming changes it simply can't be essential. It would more be a "nice to have" feature, but nothing that would block developers to wait for 10.30.

Instead we already know about several features that will only be implemented in XP 11.

The feature set for XP 10 is more or less fixed and Laminar has to work on improving their existing features!

An essential cahnge of the flight model within XP 10 would instead prove that they offer no stable plattforms for external developers! Laminar isn't so reckless instead they warned Dan Klaue not to trust on the torque "fix" completly since it is not an official feature!

[Geofa 108]

So you are saying there has been in your words " chaos" for developers and end users for the last two years ( end users who IMHO should count the more important of the two) but now it is of paramount importance that Laminar not be "reckless" because they don't want to have an unstable platform? Sounds like an oxymoron to me