Aerodynamic Derivatives wrt to u,v,w

[Simon Boudoux]

Good afternoon,

I have a question regarding VSPAERO when I am looking at the STAB file after performing a steady analysis with Vinf and pho defined, I have my aerodynamic coefficient about alpha, beta, p, q, r and all but I don't have about u, v, w is it like normal ? 

I have attached my STAB file if maybe that can help and my model with all my settings in VSPAERO if I may have put something wrong in my analysis.

Have a good day,

Simon Boudoux

[Rob McDonald]

This is normal flight dynamics process.

Assuming that you would decompose V_inf into (u,v,w), then derivatives with v,w end up as derivatives with alpha, beta.

VSPAERO does report a derivative with U -- which I believe is treated as the magnitude of V_inf.  It is usually zero because V_inf is taken out of aero coefficients.  There are some circumstances that can make it non-zero.

Rob