code: def cas2tas(Vcas, H):
      
      p, rho, T = atmos(H)
      qdyn = p0*((1.+rho0*Vcas*Vcas/(7.*p0))**3.5-1.)
      Vtas = np.sqrt(7.*p/rho*((1.+qdyn/p)**(2./7.)-1.))
      return Vtas
docs: Calibrated Airspeed to True Airspeed