The Nocilla wall reflection model has been applied in the calculation of coefficients for aerodynamic lift and drag for simple shapes in free‐molecule flows. The desirability of a model more general than the Maxwellian re‐emission model is underscored through a brief discussion of recent experimental results. This discussion also serves as a guide for the selection of parameters essential to the present calculations. The Nocilla model is shown to constitute a formalism within which the free‐molecule kinetic theory can be carried forward with comparative ease. Normal and tangential momentum transfer are calculated on a mutually consistent basis and thermal accommodation is introduced in a manner which is consistent with the sources of such information relevant to highly directed flows.