The surface-singularity-panel method VSAERO is applied to a helicopter fuselage configuration for aerodynamic analysis. The method is a viscid/inviscid interactive procedure and is capable of handing open and closed separations. Calculation is first performed for a body of revolution at incidence, which exhibits open separation ; the results are in good agreement with the data. The helicopter body at various incidences with closed separation is then computed. It is found that the panel must be properly distributed to adequately simulate the complicated separation region. It is therefore necessary to repanel the configuration when the incidence and hence the separation location is varied. The incidence that gives the minimum drag can be secessfully predicted.
