If there is no real aerodynamics here, then there is no point in discussing anything at all. The developer is out of touch with reality and does as he wants, and not as the laws of aerodynamics dictate.
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its almost like a virtual world can’t fully simulate reality
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You tell em sister!!
Yes, errors will always be unavoidable.But what I see on the charts is completely divorced from reality
And this applies not only to grippen, but to all aircraft in general
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You realize that the game by and large claims to be realistic and is trying to duplicate real world flight performance to a large extent?
Wings ripping instead of planes entering irrecoverable compression is a design decision done for the benefit of Air RB players.
If they wanted to really embrace realism then you would have to pre-trim your airplane for dive recovery.
You are not providing any insight that I don’t already know.
@Metrallaroja @Gunjob Clearly the performance is still above that which the devs claimed… is it still going to be adjusted further? Seems it’s another case of MiG-29 FM changes where I had to push for them to finally correct the high alpha behavior over the course of several reports and months of waiting.
Additionally, it doesn’t seem they’ve touched the SEP… so should Gio go ahead with his report?
edit. Why was this flagged as ‘off topic’?
The only reason SEP is high is because low speed sustained turn rate is high.
Was the same with the old MiG-29 flight model, it completely over performed in rate below 500kph, that’s why it could “pull longer” before running out of energy.
Rate and SEP are directly related, not disconnected
This was the only planned changed.
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0.2 can be just a test error, I dont see it enough to forward it.
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“dwarfs” is a bit of a hyperbole.
that and it’s REALLY hard to calculate as JAS39 has what effectively results in dynamic wing loading owing to the movable canards.
the main issue is if the wing area should include the area of the canards or not.
i have seen three numbers floating around for JAS39 regarding wing area. 25m^2, 28m^2 and 30m^2
if we use those numbers at gross weight (8.700kg) we get 348, 311 and 290 respectively.
(F-16 has 429)
if we look at the ratios of wing loading to T/W at gross weight by doing (T/W)/Wing Loading we get:
F-16: 0.26%
JAS39: 0.27% , 0.30% and 0.33% respectively
so depending on what number is used JAS39 is either: about the same, a tenth better or two tenths better. (in this very specific area)
But this is sort of a derivative of my point with point nr1 in my post as wing loading depends on weight.
and i just want to add:
Thanks to @Gunjob and @Metrallaroja for engaging with us and giving insights and answers where they can :) Great job guys!
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In game wing area is 30m^2 and canards are treated like an elevator with 4.60m^2
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The TWR difference at subsonic and transonic speeds is significantly less than the comparison you see the usual suspects giving, using the F-16s thrust @ 1,400 kph and the Gripen max thrust @ 1,200 kph. Whereas the wingloading is a fixed 30% improvement that affects the fm at all speeds.
Those shouldn’t be percentages, just ratios.
GJN includes the canards as part of the 30 m^2. I think Saab does the same. Worth noting that, as far as I know, relaxed static stability isn’t modelled for the F-16 or Gripen. Granted I’m fairly certain the physics model in WT is as simple as “this top speed and this turn rate”, so it probably won’t make any difference when they do “model” it.
oh wow. yeah that explains a lot actually. I get that there are limitations in the coding but man that’s not going to behave as i should at all.
are there any sort of plans for bigger overhauls to the FM codes? it’s getting to a point where NONE of the future added Jets (newer than what we have at the moment) will be able to be modeled even close to correctly (we even have some that cant be modeled correctly already as it is).
(just a spontaneous thought; can’t the canards be modeled as a wing? Giving them the ability to give variable lift as well as give the plane negative stability where negative pitch of canards cancels out the stability? this isn’t how it completely works IRL but i mean it will at least be closer.)
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I mean area wise, canards area is treated apart from wing area as every other elevator in the game.
And yes it produces lift, every elevator does in game but gripen canards does produce more lift than regular elevators.
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How about you take a look at the actual flight model code. It’s a lot more complicated than that (look at the full file, not just the embedded preview):
Well, a truth with modification. sure thrust will be closer, but i’m using numbers to give the F-16 the best possible chance just to show that even in those circumstances the gripen performs better.
That is why i don’t like using wing loading as a comparison. wing loading numbers assumes the same lift generated per area of wing. the in game used numbers result in a wing loading that is 48% better on Gripen. but in reality the canards cause dynamic lift so it will be a completely different amount of lift on the same wing att different AoA and speed. having a static wing will cause a (close to) linear increase in lift with speed. the JAS39 is designed to create less lift from canards at higher speeds making it basically supersonically/transonically stable but subsonically unstable. the elevons then have to help compensate somewhat for these changes in collaboration with moving the canards.
i felt it easier and more understandable to demonstrate a percentage of the ratio instead of writing 1:0,0026 or 10000:26.
as written above:
which is very weird because then the canards are treated as both pure lift (and not including the positive vortex interactions and extra lift they naturally give) as well as elevators thus producing lift only in certain situations where they also cause drag where they IRL wouldn’t.
(i’m hoping they are modeled as elevators positioned in front of center of lift and not just visually placed there but modeled as elevators behind the center of lift. @Metrallaroja ?)
i’m personally both hoping for and advocating for an overhaul of their simulations, as it stands basically none of the future modern jets they add will be able to be modeled correctly or Bug-reported with any sort of reasonability.
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Yes, they are modeled where they are visually.
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Old wiki post but you can get an idea with this:
https://wiki.warthunder.com/Flight_model_creation
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THANKS! :) Will read when i have time :)
They are already modeled incorrectly.