I didn’t quite understand your answer, the upper entrances are also used for additional recharge
Sukhoi Su-27/30/33/35/37 Flanker series & Su-34 Fullback - History, Design, Performance & Dissection
There’s a lot of threads here and there’s confusion, I was responding to Ziggi who says that the MiG 29 didn’t lose air supply at high AoA due to the upper surfaces of the intake ducts and that this was subsequently used on the F-22, thanks to the MiG 29.
The RD-33 has a very high reserve of gas dynamic stability.And the upper entrances, though, do not provide enough air.But they still help the main entrance on large AoA
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The F/A-18 ducts and fan are not flow limited in these conditions, installed thrust is higher than you expected.
Thanks to a thesis on the navy engine program we know the static installed thrust is ~16,200 lbs as stated. 16,200 x 1.1 = 17,820 lb-f thrust…
And as I also stated… I used the uninstalled public figure of 17,750 lb-f instead which is already lower. I have it some benefit of the doubt.
Anyhow that is all off topic at this point… Just my explanation for why I used that number for the calculation.
Isn’t the top surface of the intake duct shielded by the hull and isn’t it mainly about blowing excess air away ?
Why are you multiplying by 1.1? The F-18 has the same losses in the air intake as all the others.There are no new physical principles in it.This means that the thrust of 16200×0.45=7240kgf has already been given taking into account losses
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Yes the MiG-29 had a better ability to breath than most fighters at high angles of attack. It is a a high alpha fighter after all & is the only other fighter of the 4th generation classified supermaneuverable. It lacks the aerodynamics for controlled side slipping & limited to dynamic decelerations. The aircraft is equipped with the massively powerful RD-33s.
Airflow is distorted at the intake inlets when operating at angle of attack. As the degree of alpha increases, distortion increases. The engine is starved of adequate oxygen & thrust drops.
At high angles of attack airflow separation occurs at the intake and airflow within the inlet pools begins to swirl & vortices develop.
This disruptive airflow will reach the compressor unevenly & will result in a compressor stall.
A compressor will only pump air in a stable manner up to a certain pressure ratio. Beyond this value the flow will break down and become unstable.
Of course the intake louvre the top of the MiG-29 LERX assist in providing stable airflow to the compressor & prevent airflow from pooling. Airflow still travels along the LERX when the aircraft pitches & enters the intake.
Why would the MiG 29, a fighter designed for alpha flight not have any auxiliary intakes to assist it? It’s supermaneuverable capable. It’s nonsense to think it didn’t.
Was the intake louvers a perfect design? No. the most modern MiG-29s no longer equip the intake louvers or duels mode intakes & have simple but effective network of perforate panels through out the aircraft, within the wheel well of the landing gears etc. that provide stable uniform airflow to the compressors in the entire flight envelope.
The Su-27 has its intake louvers placed under the aircraft’s fuselage on the engine intakes & inlets at a slight angle so that when the aircraft pitches in alpha flight airflow pushes the louvers down & provides stable airflow to the intake inlet precisely where there is distortion.
How would this not help the Su-27 in high alpha flight & supermaneuverability?
You actually believe the su27 only have one ability to intake stable airflow?
I don’t think so, but it doesn’t matter. I tried DCS and the “gills” don’t open at higher AoA at 9-12.9-12S, also the manual for the MiG 29G doesn’t mention them opening at higher AoA.
But I still think some small effect could be there, as BRCRF wrote. Nothing extraordinary.
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The new MiG aircraft use a controlled air intake edge for continuous flow at high angles of attack
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@Ziggy1989 you guys are arguing about many things regarding SU-27, but all i know is that in the game the FM of SU-27 is utterly horrible and worthless.
Instead of arguing on such things, could you guys make reports about SU-27 FM? i really doubt a plane designed for dueling and maneuverability would be this shit in dueling and BFM. It is utterly horrible to use.
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tests are needed. STR at different heights and different speeds, rate G, acceleration 600-1100 km/h 1100-1300 km/h per 1 km.
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I know it does not matter in the grand scheme of the game.
I do like conversing with you on your thoughts on the aircraft. This is not a way to trip you up. I am simply providing additional context such as the compressors of the engines. They require a very balanced, even airflow to compress the air without surging. These engines are very delicate at the compressor & are highly susceptible to disrupted airflow. The issues can range from Rotating stall, Axi-symmetric stall or compressor surge to total engine flame out.
The ability for airflow to reach the compressor evenly at angles of attack is critical. That is why the Su-27 & Mig-29 have such large main intakes. But large intakes alone cannot limit the distortion & disruption of balanced airflow to the compressor. Auxiliary intakes are needed.
The only reason I provide additional perspective that loss of thrust is just one concern of alpha flight. A Flame Out is worse & is a higher likelihood for aircraft that are designed to operate at such extreme angles of attack. I just want you to be armed with additional perspective for your review that’s all. I did not spend the time typing all that because I did not value your evaluation.
Just wanted you to be armed with additional information that is rarely discussed on the forum for your review.
Right, most are under the impression these are minor effects on the aircraft as well. It’s easy to forget that compressor stalls exist, especially at high angles of attack in a game where none exist. Angle of attack is detrimental to engine performance.
If the Su-27 is capable of exceptional flight performance that is beyond traditional aerodynamic technique at angles of attack beyond maximum lift, then in must possess exceptional technologies.
One of many is the aircraft ability to provide stable, balanced airflow in such extreme conditions & not flame out.
The exhaust & auxiliary exhaust on high alpha fighters are pretty distinguishable for a reason. No other aircraft have such large main intakes & auxiliary intakes. Again, just providing some additional perspective for review that’s all bro.
I am working on collecting sources that N001VP (N001VEP) has additional search modes & increase to targeting range at the very least. There is no reason why the SM radar be another copy paste. It should have all the upgrades & of the exported version in Su-30MK2-based SMK mid-life upgrade & some. I am expecting them to model it in soon. But just researching and saving.
As for the FM I am not sure what can be done in mouse aim. I would refer to @BBCRF or @_Fantom2451.
My issues are in full real, when performing supermaneuverable techniques, the aircraft likes to randomly stop mid turn, pause & drop straight down as if there is no momentum to carry the aircraft like the instructor switched back on.
I’ll move this to the F-18 thread.
Sounds like you flatly stalled because you didn’t rapidly attain enough inertia to cause sufficient overshoot as described by TsAGI
Thus, forcing the AoA requested results in an inability to recover from the expected stall.
Why move it to the F-18 thread?
You already spend the entire day yesterday lying how much better an US naval support attacker is better than both the Su-27 & Mig-29 in every way. Why leave now?
You spent all day lying about the Su-27, misrepresenting its aerodynamics & engine performance trying to nerf it.
90 Degrees for the Mig-29
Ummmm… You don’t even know what Lift is.
You thought Bisonic was a real speed regime & an actual word…
“We know the FM’s aren’t correct but the high alpha performance is as good as it historically could be”
"60° AoA with nose approximately 90° from the ground is the MiG-29’s ‘Cobra"
What hell are your you talking about???
The word “ground” is not found a single time this study… This guy actually has no idea how angle of attack is measured… It has nothing to do with your nose’s relation to the ground. Where did you interpret this?
Straight making up nonsense to convince others that their models are not underperforming & nothing they can do at the same time. How miserable does someone have to be to do this? It has nothing to do with the ground.
Does anyone want this entire study to see for yourself he keeps referencing nonsense.
I have you the link to the article, it supports what I said if you read it fully. The MiG-29 does not overshoot to a true 90° alpha. That single sentence just conflated them.
I moved the F-18 discussion to the correct thread, you’re free to continue rambling over there if you’d like but I’d prefer you contained your nonsense to a single thread or topic at a given time. You make yourself look bad regardless.
Word of advice, I wouldn’t go around telling people they don’t know what they’re talking about if you demonstrated your lack of knowledge in the same or previous posts. Just rely on sources and let them speak for you. That’s why my reports get passed… Note that the MiG-29’s real AoA capabilities were amended because of the reports I made… You don’t do anything to improve the game.
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