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4

Simply using the generic drag equation will get you within the ballpark required for FlightGear. $$D = C_D \cdot \frac{1}{2} \rho V^2 \cdot A$$ with $C_D$ the flat plate drag coefficient and A being a reference area of your cowl flaps. The data for the correct Reynolds number is best used, with $$Re = \frac{\rho V \bar{c}}{\mu}$$ with $\bar{c}$ = mean ...


18

Your scepticism is justified. The critical angle of attack (cAoA) can grow as well as shrink with increasing airspeed. Growth is generally due to a higher Reynolds number while a reduction in the cAoA with increasing speed is a transsonic effect, so it depends on the flight Mach number. In one peculiar case this already stated to happen at Mach 0.3, far ...


3

Yes One way to gain greater understanding is to go to airfoil tools and observe the lift vs AoA of your favorite airfoil (try the Clark Y for starters) and you will see that Reynolds number effects generally occur across several orders of magnitude, well outside the speed envelope of your aircraft. A bit like saying from 0 to Vne would be a few centimeters ...


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