Checked again to be sure, but at 5000m it matches the chart very well, within margin of error.
This probably means that drag is too high while thrust at high altitude is too high
Sukhoi Su-27/30/33/35/37 Flanker series & Su-34 Fullback - History, Design, Performance & Dissection
will look into it
The one you asked: SU-27SK Aircraft Flight Operations Manual (Book 1) : Russian Military : Free Download, Borrow, and Streaming : Internet Archive
This one is a comparison of the 27 to F-15, F-16, and Tornado. It has some graphs at the end from tge normal Su-27 manual. The mass is not directly given, but the wing loading is at 305 kg/m^2. For this particular manual, speeds are it TAS, unless otherwise specified.
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It might “miss” chart because of constant oswald
BTW, gaijin doesnt care about stuff like that. “close match to any altitude and speed is not key target for WT FM.”
https://community.gaijin.net/issues/p/warthunder/i/9LFJm1a6EfsD
At 1000m and 460kph IAS it is underperforming by a lot, about 0.5G (3.0G instead of 3.5G) which is way more than with afterburner on since it is both 0.2G more and the total Gs are lower.
Looks like the plane has too much drag and a little bit too much thrust
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I don’t wanna be offensive, but looking at how you are writing I don’t think you know what the Oswald coefficient is and how it works.
Guy there used WTRTI and complained about 0.5deg/sec, which is pretty much like complaining for less than 0.1G…
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In case of WT it mostly about speed loss by AOA
CBR stated that in case of Su-27 constant isnt right, which leads to a lot of stuff and sustained turn rate included. It will overperform at high speeds, but underperform on low speeds. Theres nothing to do, only wait for non constant oswald coef to match chart fully
Report link only for refference, where quote was taken.
first of all the oswald efficiency number in the WT files is not the Oswald coefficient that is there in real life or that you would actually measure in a test in war thunder.
The Oswald coefficient of an aircraft is never constant (that is right), but it always decreases as AoA increases. If the Su-27 in war thunder had a constant oswald coefficient it would actually over perform at low speed since at high speed the performance is right.
The only aircraft in war thunder where the oswald coefficient was constant was the gripen before may, when it still had a wild flight model (you can check my thread about it if you are interested).
To make myself clear again, right now the Su-27 in war thunder does not have a constant oswald coefficient.
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Here it is, give it some “I have the same issue” :D
https://community.gaijin.net/issues/p/warthunder/i/pMIS9A3vdNzU
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I love how you tested all of the stuff regarding the su-27 and made a report all in 1 day lol, absolute epic.
Gaijin owes you a lot for correcting their shit.
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I am betting they will say you are using 4×R-73, instead of 2xR-73 and 2x-27.
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At least in the second video (the one at 100% throttle no AB) they can’t :D.
Also luckily the flanker is quite stable in a sustained turn, so it doesn’t take too long to get an acceptable run if I need to do it again.
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thanks for quality report good job mate
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The weight is is still weird to me.
The devs say that the referense weight is with 4 missiles and 5200 kg fuel totaling at 22800, and that at 50% of that fuel load it should be 20200.
But the manual gives the reference weight at 23250 with fuel weight at 5090, so half of that should be 20705.
What total weight did you do the test with?
@BBCRF, do you know if “расчётная взлётная масса” refers to the same fuel load as “нормальная заправка?”
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20200kg, just to be safe without going against the devs.
This whole weight thing seems strange to me as well, especially considering that the 0.3G I reported, while very much noticeable, would bring the Su-27 to about the level of MiG-29As in low speed STR (which is still a huge jump considering the flanker current state), and the Su-27 doesn’t have the massive increase in rate that the MiG-29s have at higher speeds.
Considering that the flanker, being aerodynamically unstable, should outperform the 29As in low speed STR there might still be something left on the table
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I’m wondering, what’s the best sustain turn rate of the Su-27 right now ?
If I remember correctly in Ride2R sustain turn rate tests with 30 min of fuel the Su-27 could out rate the 29 by a small margin, and from the tests at 200knts it already outrate the 29 at low speed. Here is the doc just in case Sustained turn rate tests - War Thunder - Google Spreadsheets
I hope your bug report work, Su-27 would be amazing tbf !
Thanks for your work ;)
The sustained rate of the Su-27 isn’t relevant because every foe it faces forces it to “tighten down” continuously or they simply climb in the rate. Trying to rate fight in the aircraft is only possible with full real and careful control / maintaining a higher airspeed.
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I know rating at low speed is a bit of an imaginary thing an may happens really only with full controls like in SIM, but if I’m not mistaken the fact it doesn’t rate as well as it should be means it has less energy retention ? And from what giovanex said it may have too much energy generation if I understood it correctly
It says there. That this is the estimated take-off weight. This is a normal refueling of 5090 kg and 4 rockets 2 R-27 and 2 R-73