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PMDG 747 - My thoughts and constructive criticism?

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Romain Roux



Avec l'avion, nous avons inventé la ligne droite.

St Exupéry, Terre des hommes.

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Thanks Bud, I appreciate your time.  I'd seen that, and it goes right along with what Lefteris told me personally.

I worked the Majestic Dash 8 Q400 (true external flight model) for over 6 years, and what Lefteris has said is not the same as using an external flight model. It's just not remotely the same - in fact it's apples and oranges (but still fruity... lol!).  One would really have to understand the how the ESP flight modeling works, which would lead them to why FSL had to use a little external calculations (which I'd bet has to do with the FBW/feedback) as there is nothing in the ESP model that handles that. Then one would have to understand the differences say to the NASA flight model used in the Majestic Dash 8 to truly understand the difference between them.  Again, this is not an external flight model, but rather a few calculations simply because they didn't exist in the ESP model.  This is not even close to being semantics, and it's why Lefteris won't say an external flight model was used.  He's a great, and honest guy!

Again I'll say, terrific product, works great and there is nothing at all wrong with using the ESP Flight Model for everything except a few FBW calculations!  I just think it's important to be accurate about the product.  After all we're flight simmers, not gamers, so let us be accurate about the products.

I thank you again my friend, and wish you the very best.




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5 hours ago, G-CIVA said:

##### are you on about?

If the aircraft weight is such that the VREF 30 +100kts SPD is going to be BELOW 250kts then in ECON CLB Mode the aircraft WILL HONOUR the 250kts restriction below 10000ft, if the aircraft weight is such that the VREF 30 +100kts SPD is going to be ABOVE the 250kts restriction below 10000ft then the aircraft will honour this SPD in ECON CLB mode below 10000ft which WILL BE a number greater than 250kts.

To achieve clean or flaps UP configuration the aircraft MUST fly faster than 250kts due to all up weight & ambient temperature & pressure.

How hard can this be to understand?

 Steve, here is a direct quote from my first post.

"4) Comments  that may be out of my knowledge (possible bugs?)"

Please could you explain to me why I received such a heavy handed response to a very gentle self-observation to which I say may be out of my knowledge?



So with the picture below I am referring to my point where the flaps up speed is lower than VREF 30 + 100. That's where I am confused.


(direct link http://tinypic.com/r/24b6kpk/9 )

17 hours ago, G-CIVA said:

Because Alex the VREF 30 + 100 speed which BTW is the minimum CLEAN speed for a B744 may actually be ABOVE 250kts.

Do you expect Boeing to restrict their 'heavy; aircraft to 250kts below 10000ft by default & keep them dirty with a selection of flap deployed just to honour the 250kt restriction because rules are rules?

How would that affect fuel economics & noise pollution?





Alex Ridge

Join Fswakevortex here! YOUTUBE and FACEBOOK

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11 hours ago, aceridgey said:

I'll double check though but if the min clean is below 250knots, is there a problem if VNAV SPD is above 250knots below 10,000?


On 2/27/2017 at 2:34 AM, aceridgey said:

a) why is there no 250/10,000ft speed restriction in the fmc by default?

Speeds above 250/10,000 are allowed in the US without requesting it from ATC for Heavy aircraft/Safe Operations.  There are a couple exceptions such as Chicago which specifcally states in the charts 250 until instructed (this includes above 10,000.)  The rest of the planet though we ask for unrestricted speeds in the climb.  The only place I have ever had an issue is in Germany where they insist on you flying with the slats out til your above 10,000.

Brian Thibodeaux | B747-400/8, C-130 Flight Engineer, CFI, Type Rated: BE190, DC-9 (MD-80), B747-400


My Liveries

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I really think it was about time with a thread that suggests PMDG to externalize the flight dynamics from fsx.

On another more serious note there is some nice suggestions on this list 



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On 27.2.2017 at 0:34 PM, aceridgey said:

c) - FIX page FPS drop - I've historically talked to the TECH team about this known issue where FIX page range rings bring FPS down significantly, I hoped this would be fixed for the 747 release but have noticed it here.

I had hoped this is at least solved in the actual release. Btw. is the Captain PFD popup crash issue solved meanwhile, as known from 77LR/F. The funny thing i don't have it with the 300ER.


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Since the comparison has been made, generally speaking, I've found that the FSL A320 and the PMDG 747 are comparable in most repects in terms of offering good stuff. Sure, the FSL A320 is undeniably a tour de force of realism simulation, with all kinds of super nerd-level stuff going on, so I think it probably edges it in that regard, but that is not to say the PMDG 747 is a slacker; for one thing, the 747 is a damn sight cheaper, and for another, it offers a ton of variants (more than most people probably even hoped for). so what we lose on the roundabouts, we gain on the swings

Of course, any super-duper newly-added features and tweaks would be great, but I've pretty happy with where they both sit in terms of what they offer us.

Alan Bradbury

Check out my youtube flight sim videos: Here

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4 hours ago, aceridgey said:

 So with the picture below I am referring to my point where the flaps up speed is lower than VREF 30 + 100. That's where I am confused.


(direct link http://tinypic.com/r/24b6kpk/9 )

Nothing confusing there Alex, the Flaps UP SPD is calculated as VREF 30 plus 80.  Apologies, I misquoted this as being VREF30 plus 100 earlier - my mistake.  It is VREF 30 plus 80 for a clean configuration in the B744.

The ECON CLB SPD is the SPD you should be looking at which is VREF 30 PLUS 100.

Take a pretty picture under similar conditions showing the VNAV climb page that's why in this picture you are exceeding the 250/10000 restriction.

It ain't rocket science.

Steve Bell


"Wise men talk because they have something to say.  Fools talk because they have to say something." - Plato (latterly attributed to Saul Bellow)


The most useful tool on the AVSIM Fora ... 'Mark forum as read'

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