Sukhoi Su-27/30/33/35/37 Flanker series & Su-34 Fullback - History, Design, Performance & Dissection

Nope, what I said is that, for the flight model to be correct, the sustained turn rate must be followed across the whole speed envelope.

I’ll try to be more clear:

A sustained turn rate chart refers to a certain altitude:

If at that altitude, the sustained turn is correct at all speeds in the interval from “[speedA ; speedB]” and, during those sustained turns, the aircraft reaches AoA values in an interval [AoA1 ; AoA2], then SEP will have minimal inaccuracies at that altitude in the intervals [speedA ; speedB] and [AoA1 ; AoA2].

The most probable reason on why the Mirage2000 is underperforming in SEP in you test is because the aircraft has too much drag (aka has too high drag coefficient Cd) when producing the lift coefficient Cl to achieve that particular turn. Cl is also, provided that altitude is constant and speed doesn’t go transonic, directly related to AoA.

Since you were pulling ~27 degrees of AoA in your test, we need to look at how much drag (how high is Cd) the aircraft has when producing the lift coefficient that corresponds to that AoA.
In the sustained turn chart, this value will be reflected in the turn where this particular AoA is reached.
That’s why in the case of the Mirage we need to look at a sustained turn that happens at much lower speed than the one you tested the sep at.

For the same reason, if the Su-27 sustained turn gets improved by those 0.3G at low speed and the drag is reduced, that reduction in drag will help the plane every time it is pulling the AoA I pulled in the test, even at higher speeds.

hopefully this way is clear

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yes

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I think we are talking through a language barrier here.

Either way I think this is the response your bug report is going to get.

Perhaps, although it doesn’t seem so to me, or at least I think I have understood pretty well what you said.

Might be, hope not. Again thought, that test refers to a different chart, used (according to the devs) a wrong weight (I used the same weight the devs said to use for the chart in my bug report) and speeds are higher than the ones I tested at.

The roughly .4G under-performance at around 460kph is in-line with what other people have bug reported. It has been kicked back every single time.

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Are you sure? That’s a considerable difference performance-wise

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MiG-29 SEP value is incorrect, that is obvious. I don’t know how you jumped to that conclusion.

No, you’re intentionally pretending to not understand his point.

Why are you so adamant? Is there some sort of dopamine response to guessing and being right? What if you’re wrong? Certainly you have not the faintest clue how they’ll respond.

No, it hasn’t.

Even when issues were small, continuous reporting and pestering eventually led the devs to fix the issues.
https://community.gaijin.net/issues/p/warthunder/i/H409F96xHyZa
https://community.gaijin.net/issues/p/warthunder/i/YUEVxqaLf1xw

They marked them as “not a bug”… fixed them anyway. Good to go.

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In-game sustained turn values at 20,000kg (which is the reference weight on Su-27SK chart posted earlier.)

300kph = 2.2G
350kph = 2.6G
400kph = 3.2G
500kph = 4.2G
600kph = 5.5G

Real values.
300kph = 2.5G
350kph = 3.0G
400kph= 3.5G
500kph = 4.6G
600kph = 5.8G

It is underperforming in terms of sustained turn rate by .3-.5g when compared to chart values. As far as Gaijin is concerned this is within their margin of error based on all of their previous responses.

Ahh yes…the very good MiG-29 fix where they also nuked the energy retention/SEP of the flight model into being abysmal dogshit.

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Please keep it PG in here, no need to get angry because you can’t admit error in your judgement.

Yes, and more so in terms of energy retention. Any such discrepancy warrants a report. Gaijin has fixed or adjusted several FM’s to match charts like this. Even more recently they adjusted the weight of the Fakour-90 by just 1kg to match the data I presented. Small adjustments are not new, and just to look at the G value (not even degree / sec sustained turn)…

2.5G / 2.2G = 1.136
That is 13.6% difference in sustained turn rate at that airspeed. There are larger gaps in that array there. 13.6 is 100% within the reasonable “fix” window.

Even basic upgrades to the airframe increase performance more than that. Being short 13.6% is like flying a stock performance plane around when you could have had it fully upgraded.

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My guy…the flight model is garbage…but hey at least it can cober now. Pretty much every Western plane will slam it in a dogfight in Sim and it’s not really a close fight. It has the same issues with poor specific excess power that the Su-27 does.

It’s already been reported. It gets kicked back every time and the devs say that the sustained turn rate in-game matches the charts.

Maybe it gets fixed now by some miracle but I very much doubt it.

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I mean, it matches the G charts in all of the specified speeds…

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As i know it even overperforms at high speed

That was in regards to your language decisions.
The high alpha performance was horrible, having sustained turn rate worse than the F-16 or Gripen at the time as well. The aircraft now has at least one advantage it can utilize with the R-73 as opposed to nothing.

Of course it is still wrong, but you antagonizing the people trying to fix the FM’s does what exactly?

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Yeah tbh, don’t know where to stand with the MiG-29 or Su-27 FM either…

From all that @Giovanex05 told me, MiG-29 should match most of his charts and probably would be one of the most realistic aircraft we have in game.

It may be underperforming in some areas… if @MiG_23M think it may be the case, that would mean it needs to be taken care of and tested in the proper thread.

As for the Su-27, seems like Giovanex bug report may help the aircraft under 600/500 kph where it struggles the most, taking a look at thrust maybe important as well since it seems to be overperforming.

Still, those aircraft needs a fix if they underperforming, even if it seems to be a big a small amount. (As long as Gaijin does their jobs xD)

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We should wait and see what happens, I’m still a bit skeptical but the “if it matches the G charts in all of its specified speeds then it’s most likely right” feels convincing to me. I’m super dumb regarding these technical stuff and unfortunately for now i’m not having much free time to search about it, so my positions aren’t that reliable you know lol.

Btw @MiG_23M, what makes you think that SEP is incorrect in the case of the fulcrum? We can also bring this topic to the mig29 thread to avoid spamming stuff that don’t have much to do with the su-27.

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Sustained G loading requires very little AoA. The coefficient of lift and drag can be correct for lower AoA.

In regards to energy loss at higher angles of attack, it is excessive and doesn’t match the expected performance. Not even close.

There are charts in the manual that could be used to test this but to be quaint, I’ve been lazy. They’ve also sat on the F-16 issue for some time.

They may also sit on the Su-27 issue.

The reason: none of them have been easy fixes.

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I think one of the major problems about the state of Russian Aircraft is less obvious right now.

The Human mind tends to prioritise the immediate needs over the future,

However

Since literally EVERY Russian jet after SU-27/MİG-29 is a derivative of the two, having these FMs as a base means that Russian aircraft will forever be doomed to have horrible flight models, no matter what aircraft is added.

My fear is that even when they add SU/MİG-35, they’ll be nothing but glorified missile busses that just have better engines with Thrust vectoring, while having the same FMs.

Forever dooming an entire tech tree to be a sad joke forever

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If they butchered the base Su-27 flight model, imagined how they’ll implement the Su-35 with thrust vectoring. Probably fall out of the sky after a hard maneuver.

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Believe me, they know what it takes to fix it; they just don’t want it to be good. I’ve seen the same thing happen with many planes. I don’t understand technical matters like you do, but I do understand Gaijin’s decisions. They don’t want to do this to avoid complaints from those who spend USD on the game

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