Investigation of the lift distribution over the separate wings of a biplane

An investigation is made of the mutual interference of the wings of a biplane under the general assumption that each wing may be replaced by a vortex system of the type given by the Prandtl wing theory. The additional velocities induced at each wing by the presence of the other are determined by the Biot-Savart law and converted into an equivalent change in the angle of attack, the effect being that of an additional twist given to the wings in changing their lift distributions. The lift distributions computed in this manner for several airplane types are compared with the results of measurement.