The aspect sensitivity of man-made, field-aligned ionospheric irregularities implies that the geometry of VHF communications circuits using these scatterers must be carefully designed. The design problem is sufficiently complex that it is best approached with the aid of a computerized model. Examples are presented showing the results of path modeling for man-made clouds located in Colorado and in Italy. The effects of variations in cloud height and communications circuit frequency are evident from these examples. It is concluded that geometric restrictions are sufficiently strong as to limit the application of the technique to certain specialized point-to-point or point-to-zone uses.