In game 500km/h IAS at 2000m is 550 km/h TAS
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ok so I have a mistake now I will correct the calculations
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According the 6.4 chart Ny=5.
Using Ny = 4 I also get a result around 17 degrees AoA
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I recalculated and got Nx=0.15 at V IAS -500 km/h the plane still tends to accelerate
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With overload Ny=4.1 (chart 6.14 and tables) yes, while in game it still slows down (and that’s why it is slightly underperforming).
But at Ny=5G the plane will slow down, there’s no way it can can pull 5G without Cl = Cy = ~1.323
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On the graph 6.4 at 500 km/h Nx=0. The aircraft will have a constant speed
You haven’t taken into account the contribution of thrust to lift yet Fip=5 degrees
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Yes I did. FNy is Ny converted in Newton, and it is equal to Lift + Thrust (also converted in Newton) * sin(AoA)
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The angle of deflection of the nozzle relative to the construction axis of the aircraft
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5G=(Psin(AoA+fip)+Ya)/G
from the Equation of equality Ya*cosy=G
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what is the value of that angle? (I mean value of fip)?
Also keep in mind that if fip is positive then Cos(AoA+fip) will be lower, so while you will get more thrust contribution to lift you will get less thrust to push through Drag
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Ok I’ll include it and do the calculation again.
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This will slightly reduce the angle of about 18-19 degrees
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21.63 to 19 degrees is A LOT
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I got 21 AoA Cl=1.3
Then Nx=-0.46
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Same, got 21.17 AoA → Cl = 1.3005
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Later I’ll try to calculate what weight chart 6.4. is using, that way we can use it to make a bug report
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So is the MiG-23 w/ wings fully swept a more appealing dogfight config to you than the MiG-23 w/ wings fully out because it pulls higher AOA?
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Did the calculation: weight seems to be around 11000kg (basically empty weight).
Value isn’t very precise since I had to do 2 interpolations (one similar to the one I did before: f(AoA)->Cy and another for f(Cy)->Cx), but real value shouldn’t be different than it for more than ~300kg.
Sustained AoA is 16.85 degrees, which is very close (slightly higher) to the result you got for 4G and 13000kg (and this makes sense as AoA and Cx are directly related, and the Drag force the engine thrust can overcome is always T*cos(AoA+fip) and is independent from the aircraft mass).
The reason your value is slightly lower is because in your case the plane was slightly accelerating (Nx>0).
Maximum Ny sustained for 13000kg and 500kph IAS is probably ~4.05
As usual I need to check everything again tomorrow, but since everything seems matching I’m pretty sure everything is right.
@MiG_23M if you can do the same acceleration test you did (500kph IAS, 2000m) but this time with 11000kg mass we could add this whole thing to the bug report
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I am not sure I get what you are asking. You mean un-swept? It generates more lift, yes. But the Mig23 is a very poor lifting design to begin with. Its fuselage generates very little lift and relies on very narrow wings.