The performance data for how much lift wings generate under different conditions (e.g. airspeed, wing AOA, altitude density, ....) is all tested empirically for subsonic aircraft. i.e. For new airplanes, aircraft manufacturers go out and manually test how much lift the wings generate under different conditions. There's no equation, computer simulation or wind tunnel that can accurately predict the performance data.
Is this correct? If so, then the performance testing process sounds very time and resource intensive (i.e. expensive).
Many thanks !
numerical methods can do it also, as long as the configuration is not too complex, so for a simple wing in usual flight conditions, I think it works pretty well. CFD (Computational Fluid Dynamics) results are often close to those obtained in wind tunnel for a number of classical tools. Wind tunnel can be useful anyway to confirm practically that it works, especially for complex geometries, but more and more things can be explored thanks to CFD. At the end you must test in real conditions the real manufactured product somehow...
