Are you incapable of reading anything other than your own regurgitated nonsense?
That observation was conducted by real professional aviation analyst & is also approved by professional studies. They were not baseless uneducated assumptions made by some gamer who only larps as an aeronautics engineer like yourself.
An Analysis of the Su-27 Flight Demonstration at the 1989 Paris Airshow (sae.org)
I have the same sources you do, but I can actually read. TsAGI describes the degree of alpha required to achieve Dynamic Attainment aka supermaneuvrability at regimes beginning at 90 degrees or more. Not what the Su-27 maximum degree of alpha is in every speed regime ever, especially in combat. the Directo of TsAGI will not openly disclose those numbers. Do I need to explain why?
You will not find solid open-source intelligence on it. Licensed users of the aircraft are not permitted to disclose them either. Do I need to explain why?
Why do you think the US paid a lot of money for one example of the aircraft if intelligence on them is accurately available? Do I need to explain why?
What you said was made up. No one qualified or educated on the matter would state that an aircraft can conduct a 120° AoA pitch without stalling. This isn’t possible. Total flow departure would have occured between 40 and 60 units depending on conditions.
Please read from the director of TsAGI
https://sci-hub.ru/https://arc.aiaa.org/doi/abs/10.2514/6.1993-4737
Get wrecked
This man described the capabilities of the Su-27 that day in 1989. You were not even born yet my guy. Yet you can determine who is qualified? Is that so?
Andrew Skow
](https://www.linkedin.com/in/andrew-skow-481b865/overlay/about-this-profile/)
President/CEO at Tiger Century Aircraft
Andrew Skow is an aerodynamicist, an aircraft designer, and a pilot. He has been active in the research, design, development and flight-testing of advanced, high-performance aircraft for more than 50 years. As Chief of Aerodynamics Research at Northrop, he led the development of the revolutionary Forebody Vortex Control technology that was successfully flight tested on the F-5, X-29 and F/A-18. In 1979, he was awarded the prestigious Wright Brothers Medal for his work in high angle-of-attack aerodynamics and flight mechanics. Later, as Chief Engineer for Aerodynamics, Propulsion Integration, Flight Performance, Stability/Control and Thermodynamics, he was a key contributor to the development of the F-20 Tiger Shark fighter. Since leaving Northrop and becoming an ‘entrepreneur’, he has focused on fostering innovation in aeronautics, resulting in the development of a new design approach for fighter aircraft that emphasizes Agility of the entire Weapon System, the creation of advanced air combat measures of merit for fighter aircraft, the establishment of new flight control design criteria for maximizing fighter aircraft maneuverability/agility and the development of a variable stability training aircraft for enhanced upset prevention and recovery training (UPRT). He has also co-developed a new flight deck/cockpit stall alerting system called Q Alpha that has the potential to significantly reduce the number of Loss of Control and Approach/Landing accidents in all areas of aviation from light GA aircraft to heavy transports.
Dude. @MiG_23M is so ignorant all you can do is literally just talk & lie. You have zero ability to interpret what is fact or fiction in any aircraft design. Please, do the world a favor & stop. At least go to college first.
You cannot even determine what words are made up & thought I was serious when I said bisonic dash.
Now this comment here is another example of your inability to slow down and evaluate what others are trying to teach you… I evaluate everything other say on the forum & though they think I don’t I do investigate their points. I will admit when my points do not stand after further research.
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You spewing a bunch of nonsense doesn’t excuse the fact that the Su-27 stalls to achieve >90° ‘AoA’, which is actually just the Russians stating the nose angle in relation to the ground and not necessarily the true AoA at the time. What you’re doing is trying to change the topic or discredit me… I’m not the one making the absurd claims. You are. I’m simply showing you that the people who developed the plane state it must stall to cobra.
The MiG-29 for example is incapable of 90° AoA, only around 60°. By the time it is 90° in relation to the ground, the velocity vector is moving upwards around 30°. Speed is slowed almost to a standstill and recovery is done by accelerating as the nose comes back down.
Read the source and educate yourself. The cobra maneuver requires the pilot to rapidly stall the wing to avoid uncontrolled departure symptoms such as wing rock or asymmetrical vortices loading on either side of the nose.
https://sci-hub.ru/https://arc.aiaa.org/doi/abs/10.2514/6.1993-4737
Lol look, boys.
He is attempting to ignore the fact he just lied at said no one qualified made the observation of 120 degree alpha capability in the Su-27…
You do not know what supermaneuvrability is
That is why your brain thinks it’s nonsense.
Supermaneuverability is the capability of fighter aircraft to execute tactical maneuvers that are not possible with purely aerodynamic techniques. Such maneuvers can involve controlled side-slipping or angles of attack beyond maximum lift. This capability was researched beginning in 1975 at the … See more
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You claimed the aircraft did not stall at 120° angle of attack. This isn’t true as stated by TsAGI. Nothing you say about me changes that. I didn’t lie, no one qualified on the subject would legitimately claim an aircraft could do what you claimed in that context.
Or perhaps you claim the people who designed the airframe are wrong?
It very clearly states that flow is fully separated between 60 and 90° in the study by TsAGI. It states that passage through region 30-40° must be quick to avoid disturbances that lead to uncontrolled departure.
Supermaneuverable maneuvers such as the cobra can be considered controlled departures, but are still departures. I.e. the airframe is stalled.
Depends on your definition of stall
Any angle of attack beyond CL Max where the lift coefficient begins to decrease can be characterised as a “stall” but still be providing positive lift…
Under this definition a stall would be considered anything beyond 16 degrees AOA in most aircraft…
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In this case, the aircraft reaches a speed and angle of attack that is not sustainable for a brief moment with total flow separation over the wing. Still, it produces some lift. This is a stall by any definition of the term.
Speed is not relevant to the definition of the textbook definition of a stall.
The only two relevant components are Angle of Attack and Lift Coeficiant.
A stall is not even when your Lift coeficiant becomes negative it’s when the AOA reaches a point that it starts tk decrease from the maximum CL
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Stop this nonsense.
You do not know what you are reading. You have a very basic reading comprehension. You have about a 200L reading comprehension level. You qualify for surface/simple reading & possess a basic understanding of the text.
As much as I regret to inform, you do not have an ability for In-depth/complex reading, deeper analysis & critical thinking.
You just highlighted further proof of a poor reading comprehension.
Yes, airflow seperation happens at these degrees. NO DUH.
Again, for the 6th time, what does supermaneuvrability entail?
Angles of attack BEYOND maximum lift.
The Russians will not tell you the exact alpha capability of their aircraft throughout their entire flight envelope & of each speed regime.
Do I need to explain why?
The actual Chief of Aerodynamics Research at Northrop, who led the development of the revolutionary Forebody Vortex Control technology that was successfully flight tested on the F-5, X-29 and F/A-18. In 1979, who was awarded the prestigious Wright Brothers Medal for his work in high angle-of-attack aerodynamics and flight mechanics has confirmed himself that earliest Flankers had demonstrated a 110-120 degree of Alpha.
He literally specializes in American high Alpha design. You know, that F-18 you actually think is just as capable as an Su-27?? He developed the experimental vortex control that was tested in that aircraft.
You are only armed with a high diploma as your ability to interpret aerodynamics.
Sir, I say with upmost compassion & pity… You are in way over your head trying to read, let alone lecture anyone in this hyper specialized field of aerodynamics.
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The Su-27 handbook refers to stalls as departure conditions which are dependent on speed and AoA. The designers of the aircraft refer to the maneuver as a controlled departure. Ziggy is claiming the aircraft did not stall, and still… the cobra maneuver meets all aeronautical conditions for a “stall” regardless of how you define it professionally.
This is why I said it is dependant on your definition of what a stall is.
There are several definitions and many types of stall which occur at different stages in flight.
You need to be specific.
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It is a stall regardless of definition, which means Ziggy is (once again) speaking nonsense. The Su-27 stalls to perform the Cobra maneuver. It is the very principle of it.
He does not know the aerodynamic definition of the word Stall. Just like he does not know what the mechanical force of Lift is.
I have tried to extract these precise specifics out of him before so that we may review & find common ground if his positions are correct. But he will refuse just like he is doing now to you.
That is because he knows the moment he gets specific; is the very moment you are now able to track down his misconceptions precisely & come to the realization yourself that he actually has no idea what he is talking about & never did.
He has inadvertently provided too many specifics before that came back to bite him. Now, he is more reluctant to clarify more than ever :)
Immediately denying others the ability to fully understand the logic of each position they hold is not a quality of someone who has integrity.
Our ability to be objective depends on our willingness to question our mental models, the lens through which we perceive, interpret and respond to the world. If our mental models are incorrect, then our understanding of what is going on and our response to it, are often incorrect.
He is unwilling to allow others to see through the lens he perceives on these subjects. Because he is completely aware that they are rooted in dishonesty & will be immediately rejected upon actual analysis.
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That was a long winded way for you to say you won’t define stall in a way that validates your point. This is because you can’t. What you said was nonsense.
The Su-27 stalls to achieve the cobra maneuver. It is how it is described by the director of TsAGI, what I think is totally unrelated to the fact that you’re wrong.
not that i have done anything here but it might be a good idea to focus on getting things fixed instead of just wanting to be right on the internet and constantly arguing because of it.
agree to disagree and get back to being productive, im pretty sure the things that did come out of this can also be posted without you guys trying to skin eachother alive right?
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They aren’t making any reports, I’ve assisted with several and continue to do so. The reporting page and forum are separate now for a reason - and thankfully this means long lines of discussion (even when it isn’t productive) don’t actually seriously hinder active bug reporters anymore. If you want to stop rumors and false information from spreading leaving a couple replies after pointing it out is hugely beneficial.
In any case, the Cobra implies the rapid attainment of AoA to the point of total flow separation over the wing. The aircraft maintains forward motion but the wing is stalled until airflow can re-attach and provide sufficient sustainable lift which is below 30° AoA in wide majority of circumstances for the Su-27.
listen mate, i dont care. as far as i can tell this has gone on for more than a few lines now and ive seen enough posts from both of you to take a somewhat informed guess that this isnt going to end anytime soon either. neither of you will probably ever admit theyre wrong in this, so might as well stop early and do your thing. people will form their own opinion either way so you two telling eachother that either one of you is illiterate wont do much other than wasting eachothers time :p
not trying to mini mod or anything, i often come back here to read up on some stuff so its rather disappointing to see the majority of the time spent here was spent on telling eachother we’re dumb
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