 On a biplane, since the angles are closer to the ideal of being in direct line with the forces being opposed, the overall structure can then be made stiffer.Because of the reduced stiffness, wire braced monoplanes often had multiple sets of flying and landing wires where a biplane could easily be built with one bay, with one set of landing and flying wires.The extra drag from the wires was not enough to offset the aerodynamic disadvantages from having two airfoils interfering with each other however.