Thank you so much, bit It is not 1G stal condition, it is rapid nose up maneuver - overshoot AoA in very small time - for very experinced pilots.
Sukhoi Su-27/30/33/35/37 Flanker series & Su-34 Fullback - History, Design, Performance & Dissection
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Regardless of it still is very capable of hitting 90 degrees angles of attack. It cannot come near it in game with any Mig-29 variant flown min fuel with zero weapons in full real controls. That is definitely not correct.
Yeah, that why I said its definitely capable of over 120 since that is the degree before any sign of stall. That is why I highlighted that particular airshow because there is no actual true example of set degree at stall.
I provided what evidence is available for you to determine what you think it may be at stall. Definitely over 120.
Perhaps if the onset of AoA is at 1G, the stall will occur much sooner.
Ok, let’s suppose A(x) can be written as kx+b. Let’s first try to fit it. First, at Mach = 0, i.e. at x = 0
we have 0.21 = A(0) = k\cdot 0 + b = b, so we have b = 0.21.
Next. at x = 0.5 we have 0.21 = A(0.5) = k\cdot 0.5 + 0.21, meaning k = 0.
Seems like we have found our k and b, let’s check if it works somewhere else. Say, x = 1.5
A(1.5) = 0\cdot 1.5 + 0.21 = 0.21 \neq 0.37.5.
What??
Oh no, what a disaster, it does not match.
I wonder whyyyyyyy.
OH OH OH, I know, I KNOW. Could it maybe be because it is NOT A GOD DAMN STRAIGHT LINE???
For me, lose R-27R & R-27T from Su-27SM
Su-27SM3, Su-30SM, Su-30SM2 and Su-35S not armed R-27R & R-27T
You don’t need to start from 0.And from 0.9 . To 0.9, the line is straight there are no functions
Maybe my eyes are really bad, but even there the line is not entirely straight. It curves upward from 0.75
and also is slightly curved before that. I imagine even such a small change in a coefficient would result in a decent different in performance.
No, it wouldn’t.The values are very small.You have more Cl input because it is squared
Linear
4.11.2 Stall and spin.
Stall.
The aircraft enters stall modes only as a result of the following piloting errors:
- overboosting the ODA and exceeding α limit ( 24 AoA for Su 27 SK)
- loss of speed less than 200 km/h if the recommendations of paragraph 4.11.1 are not followed.
Exceeding the α allowance by 3° ( 24+3 AoA?) results in involuntary small amplitude roll and heading oscillations. When performing intensive manoeuvring with the achievement of these angles of attack at flight speeds less than 450-500 km/h, the nose of the aircraft drifts. Further increase in the angle of attack leads to an increase in the intensity of these phenomena. At angles of attack exceeding the allowable angles of attack by 8°-14° (24 maximum +14 AoA - 38 Aoa MAX), stall occurs (significantly increased amplitude of oscillations or aircraft roll and heading).
Stall recovery should be performed by immediately setting the pitch control stick to the neutral position (1/4-1/3 of a turn beyond the neutral position away from yourself), and roll contro lstick to the neutral position with the pedals in the neutral position. During stall recovery, the aircraft may go into a corkscrew.
Сваливание.
Самолет выходит на режимы сваливания только в результате следующих ошибок в пилотировании:
− пересиливания ОПР и превышения α доп.;
− потери скорости менее 200 км/ч при невыполнении рекомендаций пункта 4.11.1.
При превышении α доп. на 3° ( 24+3 AoA?)возникают непроизвольные колебания небольшой амплитуды по крену и курсу. При выполнении энергичного маневрирования с достижением этих углов атаки на скоростях полета менее 450-500 км/ч возникает увод носа самолета. Дальнейшее увеличение угла атаки приводит к увеличению интенсивности указанных явлений. На углах атаки, превышающих допустимые углы на 8°-14° ( 24+maximum 14 AoA - 38 Aoa MAX), происходит сваливание (значительно увеличивается амплитуда колебаний или увод самолета по крену и курсу).
Вывод из сваливания выполнять немедленной установкой ручки управления по тангажу в стриммированное положение (1/4-1/3 хода за нейтральное положение от себя), по крену – в нейтральное положение при нейтральном положении педалей. При выводе из сваливания возможен переход самолета в штопор.
Fast and intensive access to ultra-large angles of attack of 90-100 degrees does not lead to stall
Yes, fast and accurate, but a 1G stall ?
There will be 1G at the end point
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4.11. Flight at low speeds.
4.11.1 Pilot’s actions in case of speed loss on ascending flight paths.
In case of speed loss up to 200-300 km/h, it is allowed to complete aerobatics in accordance with the recommendations of the flight manual, not exceeding α dop - ( 24 AoA for SK version). Question :
What is not exceed Alfa for Flanker B? I think around 30 AoA. A good pilot can go more, yes, but the limit has to be there just like the SK version, but it will be slightly higher.
Yeah, not too sure. Perhaps it already was. The aircraft was going pretty slow at the 1989 Paris Airshow.
One of the several requirements for Dynamic Attainment AKA “supermaneuvrability” is thrust to weight of 1:1+. This alone delays the stall and makes determining what G the aircraft was under at the onset difficult.
So, what does this tell you?
Funny thing is 200km is a very low stall speed for an aircraft the size of a Flanker. I drive faster than this at least once a week. Audi S5 Stage II :)
200km is a dangerously slow speed. Any degree of alpha permissible especially at what I am reading is quite impressive.
You need forward airspeed to increase alpha. I am not quite sure what we are trying to determine. The slower you are the degree of alpha decreases.
It depends on where the second Clift slide is located
I see your point, but I doubt its something GJ would consider, being as they want to maximize player incentive to GE past undesired modification. Additionally, they do want to keep these models as customizable as possible.
Hell, I personally want R60Ms available for the Mig-29s as well as R73s just to play around with old historical loadouts.
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F-15, 1G stall - around 15-0 knots - 60-70 AoA , Su 27 it will reach as BRCS said - ± 90 AoA. Actually, I am very interested to know if the average Su 27 pilot of the 1980s and 1990s could safely get above the limit given in the flight manual ( 24 AoA)
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I think the chart there is at a fixed AoA. What I am saying is that at different angles of attack the Oswald coefficient changes, in particular as AoA gets higher the Oswald coefficient will decrease as well.
That’s because lifting line theory ( Cd_i = \dfrac{Cl^2}{π\ e_0\ AR} ) comes from assuming a steady and non compressible flow that won’t detach from the wings. Lifting-line theory - Wikipedia
That the Oswald coefficient can’t be stati is pretty easy to prove as well: if we measure the real lift coefficient of an aircraft as function of AoA (Cl(AoA) or Cy(AoA) if we use Russian letters) above a certain AoA (for the MiG-29 is about 60 degrees) we would see Cl actually start to decrease, meanwhile Cd (Cx) keeps increasing. This means that the approximation Cd = \dfrac {Cl^2 }{K e_0} is not valid for high angles of attack
That’s why the devs can’t just get the Oswald efficiency found for a specific speed and use it to create a whole flight model (they seem to have done that for the gripen but I digress since the thing already got 2 nerfes and there’s no E-M chart for it)