this Mig-29M2 and my picture shows a cobra Su-27
Sukhoi Su-27/30/33/35/37 Flanker series & Su-34 Fullback - History, Design, Performance & Dissection
AoA 130,He came back thanks to pitch control, not inertia
In the SK manual there’re rolling and yawing moment coefficient derivatives with regard to sideslip angle (beta). Also known as lateral and directional static stability derivatives, denoted as Cl-beta (mx-beta) and Cn-beta (my-beta) respectively.
At M=0.2, Cn-beta is dropped to zero at 29° AOA, meaning there’s no yaw restoring moment available to reduce the sideslip. And Cl-beta is dropped to zero at 34° AOA, so no rolling moment can be generated with sideslip (by rudder).
If you compare them to the F-16:
These are two graphs of lateral and track stability, and we are talking about controllability. So mx- by delta flaperons at 28 degrees is equal to 0, and mx by delta rudder is not equal to 0 and the control moment is preserved
Yes, I’ve seen the graph of mx by delta flaperons and my by rudder some times back but couldn’t find it right now. It shows the mx-delta flaperons is zero at 28° AOA, and my-delta rudder at 30° AOA is about half of that at 10° AOA, but not at zero yet.
Yes, and the plane is still controlled by the roll using the rudder
It can, and the rolling moment is generally created by inducing sideslip with the rudder. A strong mx-beta derivative is favorable in this case.
However I’d like to point out that, mx-beta (Cl-beta with opposite sign) is also reduced to zero at 34 deg AOA at M=0.2, which means roll controllability by inducing sideslip with rudder is also not possible at this point.
For actual roll response taking into consideration the lateral-directional stability of the aircraft and the roll-raw crossfeed control, one can calculate the LCDP parameter, as explained by NASA:
In the case of Su-27 at AOA=34° and M=0.2, Cl-beta is zero, so LCDP = Cn-beta, which is already negative at 34° AOA. So the roll response will be reversed and nose slice is possible even with roll-yaw crossfeed enabled.
Likewisely, the LCDP of F-16 is also in its lowest at 35° AOA in the AOA > 25 region, but still above zero, augmented by Aileron-Rudder Interconnect. (a.k.a roll-yaw crossfeed)
And mx omega x and my omega y, as well as spiral moments
If it is above zero, then the reaction should be reversed
You are delusional where you see there pitch control??
And according to instability claims after 30-40 AoA plane suppose to not require any pitch inputs to increase AoA further
F-16 is equipped with Aileron-Rudder Interconnect (ARI) so you only need to look at the upper curve. It has a local minima at 35 deg AoA when the aircraft go beyond the 25 deg AOA limit.
Without an ARI, the F-16 would have a reversed roll response at 25 deg AOA.
You 're delusional , take a picture of an airplane and put a projection of forces on it
Right, I’m sure your decision has nothing to do with your reports on aircraft ‘overperforming’ constantly keep getting rejected by Gaijin.
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Only one of them was rejected recently, of course you would assume such things as you hold such a malice / grudge. If that’s what you think I certainly won’t be the one to change your mind. If you think the report wasn’t valid - you’re welcome to test yourself.
Out of the 80 tagged reports 23M has made, 47 of them have been labelled “Fixed” or “Acknowledged” - works out to be a 58% success rate. I didn’t count duplicates or reports not tagged.
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There are a lot of those that they marked “not a bug” and just added them to another singular report I made, or fixed regardless of putting “not a bug”.
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There’s a nice and informative debate here.
I’ll digress a bit and add the personal observations of a US test pilot.
Given Equal ‘stick manipulators’ & comparable config’, on average Flanker not an easy jet to defeat in a ‘knife fight’ (certainly below 375KCAS the Su-27 rocks, but you don’t want to go there in the F-15 if you can avoid it). They are astonishly close between 375KAS & M0.85, above that the f–15 has the edge. Unfortunately there is other stuff that makes a difference like transients …the early Su-27s (since improved) had a distinct latency in control response…it used to be a jest about take off - ‘you put that huge stick under your chin , then you wait for that F-5 wing ( the very large horizontal stabilator) to catch up’ 🙂 Pilot quality is of course decisive. Probably would take the F-15 given a choice, but no super strong preference at least WVR.